10 Questions Science Can’t Answer

There is nothing new to be discovered in physics now. All that remains is
more and more precise measurement
Lord Kelvin, 1900
How we laugh now at those daft Victorians. They thought
they knew everything. To them, the Universe was a small and
well-ordered sort of place, consisting of a few million stars.
The planets were held aloft by Newton’s well-ordered apron
strings, and the whole cosmos ticked away like a Swiss clock.
Down here on Earth they knew that life began in a warm
little pond, and that its subsequent evolution was governed
by Mr Darwin’s grand thesis. Stuff was made of atoms, of
about a hundred different flavours, which behaved like mini
versions of the planets: tiny, well-behaved billiard balls. Science
was nearing its end – all that was left was to cross the ‘t’s
and dot the ‘i‘s. We were nearly at the Summit of Total
Understanding.
The summit turned out to be a false one. A whole series of
brilliant and bothersome insights in the early 20th century
threw so many spanners into the scientific works that we were
forced to more or less rip everything up that we thought we
knew and to start again.
We now know that the Universe is rather larger, and more
ancient, than Kelvin and his contemporaries imagined. We
know how the stars shine, what they are made of and how
they evolve. We have plotted the age of the Earth and of the
planets, and have discovered or inferred some fantastic monsters
unknown to the Victorians – the quasars, neutron stars
and black holes.
2 10 questions science can’t answer yet
We have confirmed Darwin’s theories (no serious paper challenging
the basic reality of evolution has been published for
more than a century) and now have a mechanism, genetics,
to explain how information is copied from one generation to
the next. Newton’s clockwork, although a brilliantly accurate
description of the parochial, we now know breaks down on
cosmic scales and at the most rapid velocities. Einstein linked
space and time, acceleration and gravity, and mass and
energy in wonderful and counter-intuitive ways.
Atoms, previously indivisible, have been shown to consist of
a bizarre and frankly random-seeming troublesome menagerie
of fundamental particles. And on their scale, things
behave differently again from the large, the heavy and the
rapid described by Einstein. It seems that the Universe can be
very odd – spooky even. Particles can influence other particles
billions of light years apart, instantaneously. There may be
many more dimensions than the three of space and one of
time with which we are familiar. Moving clocks run slow.
Science now has theories of how the mind works, and have
gained great insights into human psychology. We have slain
many of the great killers of humankind with our medicine, and
are on the way to slaying more. We have even taken the first
steps towards exploring our nearby Universe. Some of our
technology, in the words of Arthur C. Clarke, is so advanced
that to people a hundred years ago it would be indistinguishable
from magic.
So what more must there be to know?
A lot is the answer, and that is what this book is about. There
are no great answers here, just some big (and not so big)
questions, things that science has often sidestepped or before
which it has simply wilted: challenges that have been considered
too enormous, at least until recently.
Perhaps our hubris is as great, perhaps greater, than that of
the Victorians. That is not because we know less, but perhaps
introduction 3
because we know more. The gargantuan and sustained acceleration
in scientific discovery and technological progress in
the last century, especially since the end of the Second World
War, has led to the widespread belief that the Great War on
Ignorance – the final phase of which began in the Enlightenment
more than 200 years ago – is within a measurable distance
of its end.
After all, we’ve mapped the human genome and ripped
atoms asunder into their constituent parts. A grand theory of
everything, uniting the fundamental forces and reconciling
the quantum world with relativity, may be only a few years
away. We are close to understanding the building blocks of
life, and every week it seems that astronomers make a new discovery
which revolutionizes our understanding of the
Universe. Our technology really does seem magical. Imagine
trying to explain the Web to Lord Kelvin.
And yet. Like him, we still have no idea what the Universe is
made of (or at least most of it). The Victorians presumed it was
made of just atoms, and how wrong they were. The great bulk
seems to be made of two mysterious substances, dark matter
and dark energy, whose nature we can only guess at. The ordinary
stuff (aka baryonic matter – good old hydrogen, you and
me, Neptune and your dining table) is just a sideshow. Most of
everything is invisible and we have no idea at all what it is –
just a few rather vague guesses.
We have a theory, or rather a model, for the origin of our
Universe, the Big Bang, but we do not really understand what
it was that banged, how it banged, or what lit the touchpaper.
We do not know what came before the start of our universe, or
even whether asking this question makes any sense. We do
not even know whether the universe we think of as our Universe
really is all there is. Those Victorians were out by several
orders of magnitude when they considered the Milky Way to
be all there was.
4 10 questions science can’t answer yet
We may well be underestimating the scale of things by
dozens more orders of magnitude again when you consider
that physics now takes seriously the idea of the multiverse: a
vast, indeed infinite, ensemble of cosmoses that may be
required to solve one of the great riddles – why our Universe
seems to be so finely tuned as to allow for our existence. It
could be that what we see in the night sky, all that cosmic
glory, the whirlpool galaxies and quasars, the endless voids of
intergalactic space, is just a pimple on the backside of something
infinitely grander. The true nature of reality is as elusive
as ever.
More mysteries: we do not know how life began on our
Earth, nor whether it has ever begun elsewhere.We are probably
no closer to understanding the true nature of the human
mind than Plato or Aristotle. We have no idea how exactly a
couple of pounds of grey jelly can come up with Romeo and
Juliet, appreciate a nice sunset or be in agonizing pain.
The nature of time eludes us, and the ageing process is still
something of a puzzle.We still do not know, really, why we get
old, nor why we get old at the rate we do, and nor do we
know whether there is anything we will be able to do about
this.
Much more about humanity remains puzzling. As a species
we seem to be changing shape – literally. The obesity epidemic
sounds straightforward, but in fact there are some mysteries
here. And our politicians and social scientists still resolutely fail
to deal with, or even acknowledge, the fundamental differences
between individuals that cause so much pain and grief.
The minds of our fellow creatures are still deeply mysterious,
although the more we learn, the more we are forced to conclude
that the great gap between humans and beasts may not
be as wide as we thought. What we know is hugely impressive,
but the more one thinks about what we don’t know, the
more one is forced to conclude that rather than having waded
introduction 5
deep into the sea of knowledge we have merely dipped our
toes in the water.
The sheer scale of what we don’t know still dwarfs what we
do, but you perhaps wouldn’t think so reading the papers. To
read the journals, the newspapers and the magazines, and to
watch the TV programmes that have often done a brilliant job
of popularizing some of the most difficult concepts, one could
be forgiven for thinking that most of science is ‘in the bag’.
Science now comes equipped with its own commentariat, of
press officers, professional spin doctors and Internet sites, and
of course a whole army of journalists who specialize in the subject.
Today, in the UK, there are perhaps a hundred or so
people like me who make their living writing about science for
newspapers, the Web and magazines, or making TV and radio
programmes. Fifty years ago there were fewer than a dozen.
They are needed because many scientists have themselves
often been very bad at talking about what they do. (Isaac
Newton, possibly the greatest mind of historic times, was,
famously, so terrible at communicating that his lectures were
often only attended by one or two bored students.)
Even today many scientists do not possess mobile phones,
have no idea how to use them if they do and only check their
email once a week. I know one or two who still use faxes.
There have always been scientists like this, but the difference is
that nowadays they have spin doctors, and as a result science
has become something like politics used to be, a vast ocean of
shifting opinions, tides of fashion that wash in and out (this
week it’s climate change, next we’ll start worrying about GM
foods again. Hang on a minute... we must be long overdue for
a flu scare).
All this has made boffins and their works world-class news. A
newspaper editor once told me: ‘You are lucky to be a science
writer... in the old days, science was nothing, it was all crime,
politics and trade unions. Now nobody is interested in all that
6 10 questions science can’t answer yet
stuff, it’s all global warming, cloned sheep and life on Mars
these days’. And she was right. Science has become sexy – has
made itself sexy – with the willing collaboration of witterers
like me. But there is a problem.
All this reportage is not only over-egging, but spoiling the
pudding. Whereas great discoveries once took weeks or even
months to come to the public’s attention (there was no mention
in the newspapers of the discovery of the DNA double
helix in 1952 for nearly half a year), now every scientific twist
and turn is reported as if it is the final word on the matter and
that the riddle has been solved. Nature, which reported the
DNA story, now employs a full-time press staff to decide which
‘stories’ that week are newsworthy enough to be worth troubling
the hacks with.
Medical journalism, in particular, suffers from some nasty
side-effects of over-reporting. In decades past, news from
clinical trials and large studies examining the effects of
things like diet and lifestyle leaked out slowly. Often this
meant we were simply ill-informed; many scientists were
pretty convinced of the link between smoking and lung
cancer long before the publication of Richard Doll’s definitive
study in 1954 (in fact, the link was first shown by Nazi
scientists in the 1930s, something which is still not fully
acknowledged, perhaps understandably), and yet the message
took a long time to get out that smoking could kill you.
These days even the whiff of something as comprehensive
as the Doll study would lead to a thousand magazine articles
and front-page headlines, and probably calls for
tobacco to be banned forthwith.
There was an upside to this glacial spread of information
from the scientific to the public domains. Something like an
informal process of peer-review was taking place – which
meant that only really significant studies, generating really
significant (in statistical terms) results got reported at all.
introduction 7
These days, you can give a few dozen people food additive x
and find a tiny statistical effect on their health; then ring the
right hacks and you will get immediate calls for x to be banned
straight away. The next time you read that substance or activity
x has been ‘linked’ to malaise y, be suspicious – very suspicious.
As Iwrite this I see the headline on a London newspaper: ‘Drinking
cola harms bones’. We have no reason to doubt the results
of this research, and yet one has no doubt either that in a few
months (or weeks or years) along will come another study
showing a statistical link between drinking fizzy pop and good
health, maybe even good bones. (Coffee seems to go through
a healthy–unhealthy cycle with a regular three-month period.
Maybe some strange physical law is operating here.) What
these headlines do – and the research that generates them – is
to add to the general background hum of pseudo-knowledge,
the modern equivalent of all those old wives’ tales that we sort
of never believed yet quoted endlessly.
But while we now laugh at ‘advice’ to avoid ‘indigestible’
food, put butter on a burn and avoid masturbation for fear of
blindness or insanity, and we pour scorn on the ancient terror
of ‘chills’, we have created a new folklore of our own – ‘too
much tea is dehydrating’ (it isn’t), ‘all fat is bad for you’ (you
would die without some fat), mineral water is purer and safer
than tap (nonsense) and so on. The ‘news’ can be good or bad
of course. I trawled some recent stories about heart disease,
cancer and stroke and, if all these ‘studies’ were to be
believed, I found that by eating and drinking just the right
quantities of mangoes, coffee, red wine, broccoli, fish oil and
wild rice, and going to live in the right bit of Japan I could
expect to see in the 23rd century. Similarly, I could have read
another tranche of articles and found that, with the lifestyle I
actually do enjoy, I should have been dead in 1989.
And this illusion of progress is certainly not confined to
health. In physics, the Grand Theory of Everything has been
8 10 questions science can’t answer yet
‘about 20 years away’ for at least – well, certainly a lot longer
than 20 years. Book after book has been published in the last
quarter of a century or so stating quite confidently that while
we are not quite there yet, this or that new theory will unite
the forces, reconcile the menagerie of fundamental particles,
and bring and end to the long war between relativity and
quantum physics. But – surprise, surprise – after a succession
of false summits, the goal of a Grand Theory of Everything
looks as far away as ever.
Sometimes the illusion of progress has serious repercussions,
political and social. Climate change is not just a scientific issue;
it is highly political as well. On the one hand you have a fairly
strong consensus that human activity, mostly the burning of
fossil fuels, is making a large and damaging contribution to
the global warming that has been measured since 1900. Every
month, every week, it seems there is a new piece of evidence
that seems to confirm this view. And there is little doubt that
the consensus is right. We are heating up our planet.
But of course it is not quite as straightforward as that. As the
entertaining British politician and journalist Boris Johnson has
pointed out, global warming is one of those things one
believes in or does not, and that there is the whiff of faith about
the whole climate change debate. Belief and science are supposed
to be incompatible. You do not believe in gravity, or in
Kepler’s Laws, nor in DNA; these things just are (or, of course,
are not). If you leap from a balcony your dismissal of Newton’s
laws will not help you to land without breaking your bones.
Science has never been so glamorous or so productive. It
attracts the most brilliant minds of our generation. But there is
something missing: the madness of old. Because as well as
being brilliant and inspiring, today’s science is an industry. Scientists
work in teams, their discoveries and results incremental,
their livelihoods depending on rapid publication and peer
review. It is a good process, and hard to think of a better one,
introduction 9
but it leaves little room for the lunatic and the eccentric. The
elitism and ad hoc nature of natural philosophy led to a lot of
blind alleys, but also a lot of inspiration and brilliance. Darwin’s
epic voyage round the world in the 1830s led to one of
the most brilliant and important insights in the entire history
of science, yet if you read his diaries you will realize what a
shambles, by modern standards, the whole thing was. It took
them several weeks to get the Beagle out of Plymouth for a
start. And then they couldn’t land in Tenerife because of quarantine
rules. Now, of course, there would be armies of fixers
for any sort of expedition. Today, as never before, the ‘maverick’
has a hard time in science. People who come up with theories
that challenge the consensus tend to be ridiculed, often
unfairly.
Yet even today there are free thinkers who sometimes get
round the dead hand of the consensus, people like Barry
Marshall (who discovered that stomach ulcers are caused by
an infection, not stress) and Stanley Prusiner, who proved
that the diseases scrapie and CJD were caused by a hitherto
unknown infectious agent, a protein called a prion. These
islands of brilliance punctuate an often rather flat sea of conformity.
The trouble with the big questions – the where-did-lifecome-
from questions – is that it is very hard indeed to get
research grants to try to answer them. A feature of the questions
in this book is that they often do not fall neatly into any
one discipline; to truly understand time, for instance, one
probably needs to be a physicist, a cognitive psychologist and
a philosopher.
To answer the problem of life’s origins one needs to know
a lot about geology, astronomy, possibly cosmology (let’s
assume we don’t need theology) and biochemistry. Announce
you want to investigate the paranormal or the nature of reality
and you will have a hard time getting a grant at all. Of course,
10 10 questions science can’t answer yet
plenty of people are working on these sorts of problem, but
polymaths are relatively few in number and tend to be on the
fringes.
Today, specialism and scientific correctness is all. The scientific
mainstream is channelled, focused and intensely specialized,
to the extent that these days a biochemist working on
one sort of protein structure is likely to know little of the latest
research on, say, fats or carbohydrates, let alone anything
much outside of biochemistry.
In the 1840s it was just about possible for Charles Darwin to
have a working knowledge of the cutting edge of geology,
biology and meteorology and to master the various sub-disciplines
within them. Nowadays there is simply so much complexity
– and jargon – that a Darwin simply could not emerge.
And if he did he would never get a research grant to set sail on
the Beagle.
There are mysteries because a lot of stuff is hard. There are
also mysteries that may turn out to be not so mysterious. Science
can waste of lot of time chasing rainbows. Take the ‘consciousness
problem’. From being studiously ignored for
decades, what it is that makes minds self-aware is now occupying
some of the best brains on the planet. Consciousness is
deeply sexy. But not everyone is convinced that the feeling of
self-awareness, ostensibly so mysterious and significant, is
important at all. Indeed, I know one eminent scientist who
refuses to discuss consciousness at all at the dinner table. Such
talk, he says, ‘inevitably leads just to a lot of silly speculation’.
Maybe, just maybe, what we call ‘consciousness’ doesn’t
really exist...
One of the mysteries in this book is that of time. Time is
something we all take for granted, but it is a very slippery
beast indeed when you try to define it. Thinking of space and
time together as a sort of fabric which knits the Universe
together is very useful way of approaching things on the
introduction 11
mathematical level. But does it tell us very much about what
time actually is? Might time in fact be made to disappear, in a
puff of logic, by cancelling out all those little ts from the equations?
Probably not, but there is a long history of scientists studying
things that do not exist. In the 19th century, psychologists
in the US studied a condition that was causing widespread
concern, particularly in the south of the country. This illness
was dubbed drapetomania, and its effects were pernicious and
financially damaging. Drapetomania was, you see, the ‘uncontrollable
urge of a negro to escape from slavery’. Slaves, as
well as suffering from this irrational lunacy, could also be
blighted with Dysaethesia aethiopica, or disobedience.
Drapetomania was first diagnosed by a Louisiana doctor
called Samuel Cartwright, who managed to get his new disease
written up in the New Orleans Medical and Surgical Journal.
His preferred cure for this and dysaethesia was simple: a
sound flogging. How we squirm, now, at this ridiculous example
of legitimized racism, but can we be sure that the phenomena
we take for granted and argue over today are any
more real than drapetomania? What else in the scientific
canon might be no more than a cultural artefact, a reflection
of the thinking of the times?
When you think about, it the answer to this question is ‘lots’.
Not just time and consciousness. Not everyone is convinced
that ‘dark matter’ and ‘dark energy’ are real things. Maybe the
equations are wrong, or we are making misobservations and
are thus on a Snark hunt.
It is not entirely clear to what degree the elegant world
described by the quantum physicists represents reality, or conversely,
a mathematical model of it. Modern physics is full of
wonderful models and descriptions of reality, and this is a
problem. Space–time twisting and stretching like rubber. Dark
energy stretching the fabric of reality itself apart. Tiny strings
12 10 questions science can’t answer yet
vibrating away, gravitational wormholes and clashing branes
giving rise to whole new universes. How many of these things
are real, like Newton’s apple was real, and how many are
simply abstractions, impossible to envisage except through
the lens of equation and proof? The strange world of modern
physics in particular is now so surreal, so counterintuitive, that
it has sadly left the ordinary man and woman far behind (compare
this to the works of Darwin and even Newton, which
were comprehensible, at least in their basic outline, to millions
of educated people at the time).
This book concentrates on ten questions. It is not a comprehensive
list of the greatest unanswered questions in science;
instead, it is a snapshot, taken at a particular time, of things
that have puzzled this author more than most. Some of the
questions are obvious, such as the nature of time and the mystery
of reality. Others are there simply because, well, I find
them fascinating. The obesity epidemic may not tell us anything
very fundamental about the nature of the Universe, but
it does tell us an awful lot of fascinating things about life on
Earth today and our obsessions.
Some of the great questions are not here. The riddle of consciousness
has been done to death, and I am inclined to agree
with the eminent British biologist mentioned above. Nevertheless,
it is a hugely interesting topic. I have addressed it, a
little obliquely, in the chapters dealing with animal sentience
and the continuity of existence.
Modern physics is truly a nightmare. Perhaps its greatest,
and to date completely unanswered, mystery is ‘What exactly
is going on in quantum physics?’. Paul Dirac’s famous answer
to this question was ‘shut up and calculate!’, but this will of
course not do.
For instance: when two electrons, separated by huge distance,
are ‘entangled’, meaning that what happens to one has
an instantaneous effect on the other, what exactly are we
introduction 13
seeing? How is the information getting there faster than light
(which is of course banned)? One interpretation is that somehow
a ‘message’ is being sent back in time. Another is that the
particles are ‘communicating’ with reference to a ‘universal
wavefunction’ that extends everywhere.
The role of the consciousmind is deeply odd. How does the
act of observing affect what it is being observed, as some
interpretations of quantum physics insist? And one ‘interpretation’
states that every time a quantum event occurs, a
whole new universe is created to allow for all the statistically
possible outcomes. Fine, but where do all these universes
come from?
What else isn’t here? I look at the possibility that the Universe
is home to myriad life forms, but have left the whole
UFO/ET conundrum to others. The existence of life seems to
me to be the profound mystery. The existence of intelligent
life is perhaps icing on the cake, although it would be an
extremely interesting cake if we could find it. In any case, we
may not have to look far to find intelligent life; the more scientists
probe the inner workings of the animal brain, the more
our cousins seem to climb up the intellectual pole.
We still don’t know some of the most basic things about ourselves.
The purpose of sleep (and dreaming) remains a mystery,
although new theories come along every couple of years.
Modern medicine is a triumph, and yet the embarrassing truth
is that we don’t really understand how a lot of it works. Our
brains are still deeply mysterious and not just because they
generate conscious experience.
We don’t know how, or where, memories are stored. And we
don’t know whether free will is an illusion. Proving that it is
and making everyone realize that it is would be one of the
greatest affronts to human dignity since the realization that
we weren’t designed in any god’s image, but that doesn’t
mean that the latter isn’t almost certainly true.
14 10 questions science can’t answer yet
There are an awful lot of things out there that we don’t
know. Here, for you, are just ten of them, but there are hundreds
more. It is the job of science to find the answers, and
one has no doubt that it will.
The only trouble is, one also has no doubt that, when this
little lot is cleared up, the summit of knowledge we will find
ourselves upon will be just as false as that on which stood Lord
Kelvin, and the peaks of the unknown just as high and just as
distant as they were when we mistakenly thought the end of
the climb was just one more heave away.
introduction 15
1
is fido a zombie?
16
A few years ago, I was lucky enough to find myself 11,000 feet
up on the side of a volcano in Rwanda. This central African
country is really one of the most charming, eccentric and surreal
places on Earth. I don’t think I have ever been anywhere,
certainly not in Africa, that felt more serene, cheerful and at
ease with itself. And yet, just a little more than a decade before
my visit, this country was consumed by a carnal spasm of
bloodlust rarely equalled anywhere in history.
Rwanda is not just a horror story. It also contains some of the
oddest and most picturesque scenery on the planet – the ‘land
of a thousand hills’. Rwanda is also home (along with some of
its neighbours) to one of the world’s most magnificent animals:
the fabulous, critically endangered mountain gorilla.
And it was the gorillas we were here for. I was writing a story
for my newspaper about how these huge beasts had managed
to cope with decades of civil war and strife in their homelands.
There were tales of how poachers were killing and eating the
last of these magnificent animals, whose numbers were down
to the mid-hundreds. From what I have heard, it seems probable
that the great mountain gorilla may well be on its way out.
Mountain gorillas, like their lowland gorilla cousins, chimpanzees,
bonobos, the orang-utans of the East Indies and, of
course, us, comprise the great apes. We hold our heads high
as if atop the evolutionary tree, although we deserve no such
accolade. All extant species are at the ‘top’ of whatever branch
begat them. We are no more ‘advanced’ than the humblest
Escherichia coli bacterium, although, like the gorillas and
chimps, we are certainly the brightest of the beasts. What we
also are is self-aware (which is not necessarily the same as
brightness; more of which later). Are we alone in this?
To get to the mountain gorillas of Rwanda’s Virunga mountains
entails some serious hiking. This is not hot, sweaty Africa,
but surprisingly cool-and-misty Africa. Climbing up to the
gorillas’ lair is something like walking through the New Forest
is fido a zombie? 17
– angled at 45°. It takes ages and you keep slipping and sliding
through the mud, but it is worth it.
We were extremely lucky, that cold June day. We stumbled
upon the Susa group, an extended family of some 30-odd
gorillas, the largest single tribe of the animals (comprising,
rather frighteningly, some 5% of the world’s total extant population).
There were a couple of large male silverbacks, several
mature females, and some dangerous babies playing with the
bamboo and celery.
The babies are not dangerous in themselves, of course. But
we were told that they were to be avoided at all costs. Like all
primate youngsters, they are mischievous, basically friendly
and really only want to play. And if they do there can be trouble.
‘A Japanese tourist made a mistake a few months ago’,
one of our guides told us. ‘The baby came up, and he picked it
up and held it. The silverback, ha! He didn’t like this at all. He
picked up the tourist – after taking back the baby – and threw
him up into a tree. Broke a leg. Very nasty.’
In fact, it is something of a mystery why these animals are
quite so powerful. They have, quite literally, the strength of 10
men, and are capable of snapping branches as thick as a leg.
This strength seems to confer no obvious advantage on these
animals. They are not especially aggressive towards each
other, and have no natural predators except for us. It is either a
hangover from a more red-in-tooth-and-claw evolutionary
past (their dentition certainly says ‘carnivore’ rather than
‘salad muncher’, and in fact there is some evidence that gorillas
are not pure herbivores to this day), or it is the result of
some rather complex form of sex selection, a bit like the preposterous
feathers of some tropical birds.
It is also a mystery why they are so bright (neither the environment
nor the frankly catatonic lifestyle of the mountain
gorilla is particularly intellectually demanding). But bright
they most certainly are. After hanging around for 15 minutes
18 10 questions science can’t answer yet
or so with the group, they started to get bored with us. It was
disconcerting to be this close to animals completely aware of
and yet so utterly indifferent to human presence. Most species
show either naked aggression or blind panic when Homo sapiens
is around (quite sensibly, as it must have seeped into their
brains that these nasty two-legged things will have their hide
for a rug as soon as look at them). This mild curiosity plus studied
aloofness is quite unusual. Anyway, a small group of the
animals decided to wander off through the woods, and we
decided to follow them.
The breakaway group consisted of, as I remember, two
not-quite-mature females and a young male. They looked
for all the world like a group of teenage friends going for a
walk, and that is what, I suppose, they were. They padded
almost silently through the bamboo, and led us to a small
gorge, a tangled mass of spider webs and greenery under
the canopy of the forest. In the gorge, a small but dramatic
cleft in the mountain, was a stream, and in one place this
widened out into a small pond, maybe three metres across.
The three apes then sat down around the pool. One, a
female I think, stared very intently at her reflection. I could
swear she ran her digits through her hair, looking at her face
in the water-mirror as she did so. Then one of the others,
also staring at the reflections, jabbed a hand into the water,
which of course broke up into ripples. At that point the
three animals fell about, laughing at their now-wobbly
reflections.
OK, these were animals. They were making sound, appropriate
to their species, that consisted of a certain degree of
whooping and whistling. A proper scientist, as opposed to a
journalist or tourist, would no doubt describe their change in
posture and body attitude using very different terms than ‘falling
about’. ‘Who knows what is going through their minds?’,
scientists would say, so best not go there.
is fido a zombie? 19
I’m sorry, but this will not do. Sometimes, if it looks like a
duck, walks like a duck and quacks like a duck it is easier just to
assume you are in fact dealing with a duck, rather than some
sort of complex analogy. These gorillas were falling about
laughing at what passes for entertainment in the Virunga forests.
And if a sense of humour is not a sign of intelligence and
self-awareness, it is hard to see what is.
Our attitude to animal self-awareness has historically been
odd and self-contradictory, and at the heart of it are some very
uncomfortable truths. The science of animal cognition has
undergone something of a revolution in the past 30 years or
so, and the findings are all pointing in one direction: the
mental life of animals is far more complex and sophisticated
than we thought.
Not only are animals cleverer than we once believed, they
are probably also more emotional, more self-aware and in
many ways more like us than we ever believed possible. Here,
science is on a collision course with the world of accepted
ethics and morality, and in the near future it is easy to see a
revolution occurring thanks to what we are learning. If we
decide that Fido is not a zombie, the entire relationship
between humanity and the rest of the animal world will have
to change.
Historically, as we shall see, the subject of animal rights has
largely been a matter for theologians and philosophers.
Latterly, it has been an issue for campaigners and activists. But
today, the whole issue of what ‘rights’ we grant our fellow
species has moved into the scientific domain. Not so long ago,
anyone who suggested that other species could think, use
language and tools, and show ‘human’ emotions such as love,
kindness or empathy would have been accused of hopeless
anthropomorphism and sentimentality.
Once, ‘intelligence’ in an animal was seen as purely ‘instinctive’,
and ‘instinct’, however you chose to define that
20 10 questions science can’t answer yet
rather nebulous quantity, was one of those things that
marked out a safe boundary between animals (whose every
move, however complex, was deemed to be guided by it)
and us (who, being ‘higher’ beings, are not so driven). The
cleverness of species like dogs and chimpanzees has long
been acknowledged, but until quite recently many scientists
held these behaviours to be little more than party tricks,
simulacra of conscious reasoning. They may look clever, the
reasoning went, but this is an illusion. Behind those bright
eyes is in fact nothing. Even the brightest animal is no more
than a machine, a zombie.
But the mood has changed. The more zoologists study the
behaviour of animals, the more complex and ‘sentient’ their
behaviour becomes. Science has also come close to a quantifiable
definition of sentience, a checklist against which we can
measure the ‘performance’ of various species. And, inevitably,
all this raises uncomfortable questions.
It has long been recognized that the great apes deserve special
recognition for their intelligence and presumed sentience.
Indeed, in many countries, such as Britain, species such as
gorillas and chimpanzees have acquired a unique legal status,
particularly regarding animal experimentation laws, that separates
them from the rest of the non-human animal kingdom.
But the more we find out about animal abilities the more awkward
these questions become. Awarding ‘rights’ to chimps
and gorillas is one thing, but what about dolphins? And if dolphins,
what about other mammals, such as dogs and cats?
Sheep and pigs? Crows? Fish? Hang on a minute: we eat some
of this stuff. Unlocking the secret mental life of the beasts
means opening a very nasty can of worms indeed according
to some scientists and philosophers.
We need of course to first define what exactly we mean by
sentience. There are seven ‘markers’ upon which scientists can
perhaps agree. All are possessed by humans and some by
is fido a zombie? 21
many other species as well. A very few species seem to possess
all of them.
This list ofmarkers begins with a ‘theory of mind’: the ability to
know or guess what another being is thinking. A typical ‘theory
of mind’ test would be to ask: ‘What can that person over there
see?’. Humans older than about four can do it; adult chimps
and bonobos possibly. No other species demonstrate this highest-
order cognitive skill (severely autistic people and young
children of all abilities seem to lack a theory of mind).
Tool use, once thought to be the preserve of humanity, turns
out to be very common. Various apes and birds, and even
marine otters, can and do adapt natural materials to a variety
of uses.
Plenty of species show evidence of strong emotional and
empathetic ‘abilities’, if that is the right word.
Another ‘sentience’ trait is the ability to mimic. In primates,
neurons called ‘mirror cells’ seem to fire up when we try to
copy others in performing tasks. Apes, obviously, can ape, as
can (somewhat less famously) octopuses.
Language is certainly no longer considered to be an exclusively
human trait and the ‘mirror test’ – ‘Do I recognize the
being in the looking glass to be me?’ – once seen as a key
divide between the sentient and the ‘zombies’, has been
passed by animals as diverse as pigeons and elephants (and it
is questionable how good a test it can be for species whose
visual abilities are far outstripped by other senses, such as
smell).
Perhaps the ‘highest’ quality of sentience is metacognition,
the ability to think about thinking. ‘I think, therefore I am’ was
Descartes’ famous summation of what it means to be selfaware,
and until recently it has been our ability to ruminate, to
live in a mental world apart from the world of the ‘immediate
now’ that is assumed to constitute animal thinking, that has
separated us from the beasts. That may be about to change.
22 10 questions science can’t answer yet
Not everyone will be convinced. For, despite these advances,
despite the papers in Science and other journals highlighting
the case of genius crows and dolphins, despite the
reports of extraordinary feats of sign language performed by
some captive apes and even the apparently real linguistic abilities
of some birds, there remains the whiff of pseudoscience
about the whole field of animal cognition. It is, after all,
impossible to really know what is going on in an animal’s
mind. We cannot, as the philosopher Thomas Nagel once
pointed out, know what it is like to be a bat.
Sceptics – or cynics – like to say that research in this field
is held back by an assumption that the plural of ‘anecdote’
is ‘data’. Nevertheless, casting aside sentimentality, the undoubtedly
dubious assertions of humanlike skills which have
been made by some researchers, and the paucity of hard and
fast information, there remains the important truth that the
more we learn about animals the more like us, in certain
respects, they are turning out to be.
This is new science. The evolutionary basis of intelligence
and cognition in general is still very poorly understood.We do
not know why humans became so bright. Our brains consume
vast amounts of energy (about one in eight of every calorie we
consume goes towards powering the computer in our skull)
and their sheer size makes human birth a trauma not seen in
most mammal species.
We tend to assume that our intelligence arose due to simple
natural selection – the benefits of a sharp mind for survival seem
obvious – but in fact the road to human intelligence may have
been sparked by something far more ‘trivial’ – sex selection,
perhaps. Our ability to gossip and form complex social relationships
is mirrored by some other primates, but we have no idea
why we, and not they, should have become quite so bright.
Of course, we are animals, but until recently it has been considered
that intellectually Homo sapiens almost belongs in a
is fido a zombie? 23
separate kingdom. Now we cannot be so sure. And in a century
when the roles and possible rights of animals, especially
of species that are in mortal danger like the mountain gorillas,
is likely to be thrown into ever sharper focus, then the science
of animal sentience is likely to become more than a purely academic
or philosophical debating matter.
Traditionally, the view of animal sentience was much influenced
by religion, at least in the Middle East and Europe. Followers
of the Abrahamic faiths held that the birds and the
beasts are essentially chattels, ours to do with as we will. Genesis
1:26 states: ‘And God said, Let us make man in our image,
after our likeness: and let them have dominion over the fish of
the sea, and over the fowl of the air, and over the cattle, and
over all the earth, and over every creeping thing that creepeth
upon the earth’.
This view has arguably dominated the whole issue of how
most Westerners have thought about animals right up to the
20th century. In was never the only view though. In other,
non-Abrahamic, societies animals can be viewed quite differently.
In Buddhism for example every living creature is seen as
part of a spectrum that includes human beings. Hindus see
certain animals, particularly cattle, as sacred and will not eat
or even harm them. But the Biblical view took hold in the society
that ended up developing the sciences of evolutionary
biology, ethology (the study of animal behaviour) and neuroscience.
This rather uncompromising underlying belief about
animals could be seen to have shaped our study and interpretation
in a rather unhelpful way.
But even in Biblical times there were contradictions and paradoxes.
Animals were treated badly, but religious codes arose
forbidding cruelty. Animals were so much meat, yet in
mediæval Europe they could be – and were – tried for murder.
Science, for once, took what can be seen as the traditional
view. René Descartes famously asserted that all animals were
24 10 questions science can’t answer yet
automata, true zombies whose responses to things like pain
were simply programmed reflexes.
He believed that only humans displayed sufficiently complex
and refined behaviour to indicate the presence of a dualistic
‘soul’, a ghost in the machine necessary for consciousness. This
idea was persuasive and it persuades still. An animal in pain,
certainly a mammal or a bird which is in pain, appears to be suffering
in the same way that a human who is in pain suffers.
There will be screams, yelps, and the writhing of muscles, ligaments
and skeleton suggestive of agony. We can monitor the
animal’s brain and its blood chemistry, detecting the presence
of stress hormones like cortisol and adrenaline and note that its
physical responses are identical to those of people.
Yet can we be 100% sure that the animal is actually experiencing
pain in the same way as a human being? Of course not.
It is quite possible to imagine a computer program or a robot
designed to mimic the outward signs of pain, yet clearly there
is no suffering to be had. I can quite easily program the
machine on which this book is being written to shriek ‘Ow!’,
or something like that, whenever I press, say, the letter ‘Q’. Yet
I’d have to be a moron to believe that my PC was actually in
torment.
I’d also have to be a moron to assume that when an amoeba
is challenged by nasty chemicals or intemperate heat or cold,
and wriggles and squirms, that some meaningful perception
of pain or even mild unpleasantness is going on. An amoeba is
just a biological machine, a bag of proteins and nucleic acids,
fats and water and various other bits and pieces no more likely
to ‘suffer’ than my telephone or car. This used to be seen as a
persuasive argument to ‘prove’ that animals are not conscious,
but is not now generally accepted. An amoeba is as different
from a dog as the latter is from a computer.
But not so long ago it was scientifically incorrect to argue
that animals had a mental life at all. In the 1950s and 1960s,
is fido a zombie? 25
the behaviourists, a radical school of psychology, argued that
just as it was a nonsense to argue that animals had a mental
life, it was a nonsense, too, to argue that humans had one
either. The arch behaviourist B. F. Skinner put pigeons in boxes
and mapped out complex relationships between stimuli and
responses, working on the premise that the birdbrain was a
calculating engine.
Skinner trained his pigeons to perform extraordinarily complicated
‘tricks’, pressing sequences of levers in order to elicit a
supply of tasty food and so on. What went on between the
pigeon’s ears was, he thought, not more than a continuation
of these levers, an interconnected series of unknowing mental
gearages that eventually made the animal do one thing or
another. Skinner even tried the same trick with his daughter.
To the behaviourists, what went on inside the skull was
unknowable and thus not worthy of study or even consideration.
Discussion of the ‘conscious’ mind and what this might
mean was like discussing fairies. Thoughts, such as they were,
were at best merely an internalized form of language.
There is no doubt that behaviourism had a lot of useful things
to say about how the mind works, and blew some useful mathematical
rigour into the messy and colourful playroom of ideas
that psychology was becoming. But there was a big problem.
We all know we have internal, mental lives, because we experience
them. Denying their existence because they cannot be
meaningfully studied is like denying the existence of the
Andromeda galaxy because no one has been there and probably
never will. Of course, the behaviourist could take a
solipsistic argument and assume that he or she was the only
organism alive with a mental life, and his pigeons and fellow
experimenters were mere zombies, but this would add unnecessary
complexity to the argument (why should he be the only
conscious being out of all the billions of others?). That fact
alone would take a huge amount of explaining. Today you
26 10 questions science can’t answer yet
would be hard pressed to find someone taking a hard-line
behaviourist view of animal or human consciousness.
But what does it mean to be self-aware and, indeed, conscious
of anything? After all, it is perfectly possible, as a human
being, to perform complex mental processes and not be conscious
of them. If you drive to work along the same route every
day, the chances are that during most journeys, most of the
time, you will be no more conscious of your actions than you
are of your heart beating or of your kidneys processing urine.
Try to remember your trip the next time you end up in the
office car park.
And yet, despite the fact that driving a car is a hugely complex
and difficult mentally driven process that takes some time to
master (and we can all remember what that was like), most of
the time you do not crash in a heap of tangled metal despite
having been a zombie for most of the journey. Many of our most
complicated and impressive actions do not seem to be carried
out under any sort of conscious control. We admire the ‘skill’ of
elite footballers and tennis players, but what is it that we are
really admiring when we see Roger Federer make an outlandish
return of a 140 mph serve, or Ronaldo turning on a sixpence and
blasting the ball into the net from 40 yards? After all, these
actions must almost by definition be unconscious. The skill sinks
in with the training, the hours of practice, and the guts and
determination that is needed to be in the top 1% of any professional
sport. Actually playing, at world-class level, is a spectator
sport as much for the players as for the spectators.
If humans can be largely unconscious of their actions while
playing tennis or driving, then chimpanzees can certainly be
unconscious while hunting or grooming. But this does not
mean that animals or humans are not self-aware. The question
of self-awareness is one of the trickiest in science, but what is
of the essence here is whether whatever-it-is is something possessed
uniquely by Homo sapiens.
is fido a zombie? 27
We cannot know what it is like to be a bat, a bird or a whale.
But that is not to say we cannot study and discover some useful
things about animal awareness. In 1970, the psychologist
Gordon Gallup developed the ‘mirror test’ to determine
whether animals were self-aware. In essence, the test uses a
mirror to see whether an animal can recognize its own image as
being one of itself. Plenty of animals are fascinated by mirrors,
but to see whether they know the creature in the glass is themselves,
the Gallup test involvesmarking the animal with a dye or
paint mark (which it cannot see except in the mirror) and
seeing whether the animal behaves in a way that indicates that
it realizes that the reflected body, with the mark, is its own.
So far eight species have passed the mirror test, six unambiguously
(humans, chimps, bonobos, orang-utans, dolphins
and elephants) and a further two (gorillas and pigeons) under
more controversial circumstances. Children under the age of
two fail the test, as do (perhaps surprisingly) dogs and cats.
One species of monkey, the capuchin, seems to be a ‘borderline
pass’.
The most recent alumnus of the mirror test was the African
elephant. In November 2006, the Proceedings of the National
Academy of Sciences1 reported that three elephants, Happy,
Maxine and Patty, who live at the Bronx Zoo in New York City,
had spots painted on their foreheads and were then shown a
mirror. All reacted in a way that indicated that they realized
that the animals in the reflections were themselves. They
poked their trunks into their mouths and watched the reflection
in fascination. One, Happy, passed the spot test – she
tried to wipe off the mark on her face with her trunk after spotting
it in the mirror. ‘The social complexity of the elephant’,
said Joshua Plotnik, one of the scientists behind the study, ‘its
well-known altruistic behaviour and of course its huge brain
made the elephant a logical candidate species for testing in
front of a mirror.’
28 10 questions science can’t answer yet
The mirror test could be a good indication of self-awareness
in species which are wired up in a certain way. But it is an
exclusively visual ‘test’, and for many species vision is not their
primary sense. Dogs, for instance, recognize each other
mostly by smell. If some sort of smelly version of the mirror
test were devised, we’d probably flunk. Neither we nor elephants
nor chimps could pass a test based on echolocation,
yet a bat might. The mirror test imposes a purely human (perhaps
purely primate) criterion on the measurement of selfawareness.
It still doesn’t tell us much about what it is like to
be a bat, a beagle or a badger.
What other criteria could we use to determine whether animals
are conscious or zombies? There are a range of emotions
that seem to depend on a sophisticated sense of one’s place in
the world and one’s relation to it. Emotions like jealousy, sarcasm
or humour seem to demand a sophisticated sense of self
(less sophisticated emotions like love and hate, or fear and
rage may not require anything like the same degree of mind).
So, can animals get jealous? Can they be sarcastic? Most scientists
are doubtful, but ask any dog owner and you will get the
same answer. There are endless anecdotal stories of mutts
creeping off to sleep under the bed in a huff when the new
baby arrives, or naughty puppies ‘hiding’ socks and gloves
behind the sofa and expressing great delight when their
owners express suitable frustration. Much of this comes under
the category of ‘play’ and, again anecdotally, there is a lot of
evidence that many, many species engage in play. But how
much of this is scientific and how much mere anthropomorphizing?
And, most importantly, how much data do we
have?
Not a lot. One recent anecdotal report claimed to confirm
that jealousy can be experienced by dogs. The research, carried
out at the University of Portsmouth in the UK, involved
1000 pet dogs and their owners across southern England. The
is fido a zombie? 29
owners reported many instances of jealousy, where dogs
would become upset when affection was bestowed upon
people or other animals.
The way in which this was expressed was usually by the dog
forcing itself between its owner and the person it felt was
usurping its emotions. Many dog owners report instances of
their animals trying to place themselves physically between
their master or mistress and new significant others, especially
when they are being affectionate. Such behaviour is amusing,
but may become less so when the significant other is a baby.
Persuasive though such stuff is, it isn’t really science. Owners
reporting on their dog’s or cat’s behaviour means little on its
own; this is hardly a double-blind trial. Perhaps more persuasive
are some neurological findings which suggests that animals
may be able to fall in love.
In the brains of the great apes and in humans there is a structure
composed of specialized neurons called spindle cells.
They are found in the parts of the cerebral cortex which have
been linked to social organization, empathy, sympathy,
speech recognition, intuition about the feelings of others and
emotional attachments. One area of these brain areas, the
anterior cingulate cortex, seems to be associated with an
emotional response to things like pain, sexual arousal and
hunger. Another part of the brain, the frontoinsular cortex,
generates a similar response when pain or suffering is seen in
others. The strong emotional responses we get to other individuals
– hate, fear, lust, love or affection – seem to depend in
large part on the presence of these rapid-firing spindle cells.
And it seems that the great apes (including us of course)
may not be unique. In what may be a classic case of parallel
evolution, Patrick Hof and Estel Van Der Gucht of the Mount
Sinai School of medicine in New York have found spindle cells
in the brains of humpback, fin, killer and sperm whales, and
what is more, they found a far greater concentration of them
30 10 questions science can’t answer yet
in the brains of cetaceans than in humans. Whales, Dr Hof told
New Scientist in January 2007, ‘communicate through huge
song repertoires, recognize their own songs and make up new
ones. They also form hunting coalitions to plan hunting strategies...
and have evolved social networks similar to those of
apes and humans’.
Perhaps the best way to determine sentience is the presence
of abstract thinking. Humans can ‘think about thinking’, a skill
called metacognition. It was this skill that was identified in
Descartes’s famous aphorism ‘cogito ergo sum’. Knowing what
is, literally, on your mind would seem to be a key part of selfawareness.
One traditional assumption has been that, lacking
a language with which to internalize their thoughts, animals
cannot do this. They can think about the pain they are in, but
cannot worry about the pain to come. Lacking metacognition,
animals could be said, if not to be zombies, then
certainly to lack a key property of non-zombiehood, their
inner worlds a clouded non-reflective series of stabbing
consciousnesses.
But some researchers say that it is possible to unlock the
inner lives of some species, and that they do show this property.
A psychologist called David Smith, who works at the
University of Buffalo in New York state, has been working for
some years with a bottlenose dolphin called Natua in a harbour
in Florida. He trained the animal to press buttons
depending upon the frequency of the sounds it was hearing.
When the differences between the sounds was obvious, the
dolphin had no problem (a snack was the reward for getting
the right answer). But as the sounds to be compared got
closer in frequency, to the point where even the dolphin’s
impressive hearing apparatus is unable to distinguish
between them, Natua learned to press a third button, effectively
a ‘don’t know’ or ‘pass’ button, that moved the test on
to the next ‘question’. Similar results were found with rhesus
is fido a zombie? 31
monkeys, this time using symbols in a computer game. The
tests have been refined to determine the level of confidence
that the animal feels that it has the ‘right’ answer. Smith told
New Scientist in 2006: ‘I can’t claim these monkeys show
fully-fledged consciousness, but I have shown the exact cognitive
analogy to what we have in humans, and for us it is
consciousness’.
Animals can be very bright. Apes, perhaps dolphins, and
certainly some crows have astonished scientists and the public
in recent years with displays of intelligence that were not
anticipated by early researchers. Every year it seems we get
new data that show that animals are probably cleverer than
we thought. One of the attributes previously thought to be
unique to humans was toolmaking. That notion went by the
board as soon as it was discovered, in the 1980s, that chimps
in east and central Africa could use moistened sticks to fish for
termites. One West Lowland Gorilla in the Republic of Congo,
a male named Kola, has learned to test the electric fence surrounding
his forest reserve by holding a grass stem up to the
wire. The stem will conduct a bit of current, enough to show
Kola the fence is turned on, but not enough to give him a
shock. Not all humans would be able to do this.
The fact that apes, our closest relatives, can be this bright is
perhaps not surprising, but what has taken more than a few
scientists aback is just how intelligent some birds, a group
whose very name was previously a byword for stupidity, are
turning out to be.
In the BBC television series Life of Birds, shown in 1998, some
extraordinary footage was shown in which crows in Japan
dropped hard-shelled nuts onto the road at a pedestrian crossing.
After waiting first for the nut to be cracked open by a
passing car and then for the traffic to be stopped when a
pedestrian pushed the button, the crows would land to
retrieve their nuts.
32 10 questions science can’t answer yet
This is hardly very scientific. But In 2002, a New Caledonian
crow called Betty starred in Science2 magazine after she had
learned to fashion a hook out of a piece of wire and use this
tool to fish food out of a glass pipe. That really took scientists
aback, especially as this level of toolmaking skill has never
been observed even in chimpanzees. ‘Primates are considered
the most versatile and complex tool users’, the authors of the
study wrote, ‘but observations of New Caledonian crows raise
the possibility that these birds may rival nonhuman primates
in tool-related cognitive capabilities.’
What was really extraordinary was that the hooks made by
Betty were constructed from flexible steel wire, not a material
readily available in the bird’s natural habitat. Even more
impressive was the way Betty made the hook. Crows lack
hands, opposable fingers and thumbs. To make the hook,
Betty first wedged one end of it in the sticky tape wrapped
around the bottom of the glass tube and then pulled the other
end at right angles with her beak. Betty had no prior training
and had not watched any other crows doing this. Chimpanzees
have, in similar experiments, shown themselves incapable
of grasping the principle of bending a pliant piece of wire
to make a hook and retrieve food. Some people would probably
have trouble.
The fact that at least some birds are so clever comes as a surprise,
partly because birds are so distantly related to humans.
They are not even mammals. But of course there is no reason
to suppose that ‘IQ’ (whatever that means in an animal context)
should have any relationship to evolutionary closeness to
Homo sapiens. In a review published in Science3 in 2004, the
question of corvid (crows, jays, rooks, magpies, ravens and
jackdaws) intelligence was discussed. In fact, despite the pejorative
term ‘birdbrain’, the smartness of these species has
been known about for some time. In one of Aesop’s fables, a
crow, unable to drink from a pitcher of water because the suris
fido a zombie? 33
face was too low for its beak to reach, started dropping stones
into the pail, displacing water until it was within reach. For a
very long time, tales like this have always been dismissed as
hearsay and folklore, which of course they are, but it is interesting
that it has only been very recently that science has
started to discover that many of the things lay people have
thought about animal intelligence might be true. ‘Recent
experiments’, the authors wrote, ‘investigating the cognitive
abilities of corvids have begun to reveal that this reputation
has a factual basis.’
The authors speculate that intelligence evolves not to solve
physical problems but to process and use social information,
such as who is allied to whom and who is related to whom,
and to use this information for personal gain and deception.
This is all very well, but you need the equipment for the job,
and here the crows and their relatives seem to tick this box as
well. The crow has a significantly larger brain than would be
predicted for its body size – in fact, on this measure it is similar
to that of a chimpanzee.
Among the bird family, only some parrots have larger brains
in relation to body size. The crow’s brain is also particularly
well developed in those areas thought to be responsible for
‘higher’ thought processes, a region of the brain dubbed the
‘avian prefrontal cortex’ as it is thought to be analogous to the
structure seen in mammals.
Not only have crows been seen making hooks in captivity,
their behaviour in the wild shows some extraordinary abilities.
For instance, they cut pandanus leaves into a series of
sawtooth spikes and use these to impale grubs and insects
gathered from under vegetation. Many corvids store food for
future consumption; they are not alone in this of course, but
what is extraordinary is that they seem to be able to distinguish
between perishable and longer-lasting supplies, and
return to their cache before their stores have gone off. In labo-
34 10 questions science can’t answer yet
ratory studies, birds will not bother to return to a store of dead
grubs, say, after a long time has elapsed, but will return to find
seeds. This suggests a ‘what, where, when’ memory much like
ours. These birds are also able to create complex strategies to
cope with thieves. They hide their food where other birds
cannot see it, or wait, their beaks stuffed, for other birds to fly
away or turn aside before hiding their store. And birds who are
habitual thieves tend to be better at hiding their food than
ones who have not.
These birds, in other words, show flexibility, seem to be able
to work out what others may be thinking, understand the
principles of causality, show imagination and can plan. Most
importantly, their behaviour strongly suggests that they are
able to put this ‘cognitive toolbox’ together to construct an
internalized image of the world. Does this mean they are fully
sentient and conscious? We don’t know. But it is good evidence,
surely, that they are.
Betty and her relatives are impressive enough, but they cannot
talk. Some birds are, of course, able tomimic human speech, but
it is only quite recently that anyone has suggested that they are
able to understand what they are saying. Alex, an African Grey
parrot, has been studied for nearly 30 years by the animal psychologist
Irene Pepperberg in the US. His vocabulary is about
100 English words, and he seems to understand what they
mean. Pepperberg has claimed that Alex understands concepts
such as shape, colour andmaterial, and can use English correctly
to describe these concepts. Alex also apparently shows remorse.
He was even able to make up a word – ‘bannery’ – when shown
an apple for the first time (he already knew about grapes and
bananas). Another African Grey in the US, N’kisi, is, its owner
insists (some scientists are skeptical about N’kisi), capable of
using language to have a real conversation (a claim that has not
been made about Alex). N’kisi is supposed to be capable of
humour and even sarcasm. He invented a new term when faced
is fido a zombie? 35
with aromatherapy oils – ‘pretty smell medicine’ – although
whether his sarcastic attitude extends to alternative therapies is
not known. And it’s not just parrots and crows. Sheep have now
been found to recognize dozens of individual people. And earthworms
have been spotted doing differential calculus (just kidding).
Cleverness is not self-awareness. The fact that crows can
make tools out of wire does not necessarily mean that they are
sentient. But intelligence may well be linked to consciousness.
That the brains of mammals, reptiles, birds amphibians and
even fish share common structures and genetic backgrounds
suggests quite strongly that our self-awareness is almost certainly
not unique. Because not to draw this conclusion would
be to assume something very strange indeed, something
along Cartesian lines – that somehow, at some point in the
evolution of Homo sapiens, and Homo sapiens alone, something
magical invaded our skulls in the Pleistocene and set up
home.
So where does all this leave us? In an uncomfortable place,
that’s where. If we assume, as I think we must, that animals are
sentient, aware beings capable of conscious thought and of
distinguishing themselves from the rest of the world around
them, if animals are not zombies, then the distinction
between them and ourselves becomes somewhat arbitrary. As
some people have argued, eating them is no different, morally,
to cannibalism (indeed it is worse, because at least with
cannibalism there is the possibility that the meal can give his
or her consent to be eaten).
It is certainly uncomfortable for us that the more we learn
about animals the more impressive their intellectual capabilities
appear to be and the more, biologically, we seem to have
in common. This can of course be overstated. It is an overquoted
factoid that humans and chimpanzees share more
than 99% of our DNA, but it is a much less quoted factoid that
36 10 questions science can’t answer yet
we share two-thirds of our DNA with the halibut, and we are
well into double figures with yeast. And anyway, what does
this mean?
Humans and chimps may be on neighbouring twigs on the
evolutionary tree, but mentally we might as well be in different
forests. Nevertheless, things like tool-using, language, a
sense (perhaps) of fairness, and even emotions like humour
and jealousy – all once thought to be the preserve of people –
have now been observed, to greater and lesser degrees, in
animals. It is likely that the more we probe the minds of the
apes and monkeys, elephants, dogs, birds and probably even
fish, the more impressive will be the intellectual machinery we
will discover. Even invertebrates are not immune to this animal
‘intellectual revolution’; some cephalopods – the squids, cuttlefishes
and octopuses – are so bright that they have won
legal rights in some jurisdictions to be protected from certain
painful experimental procedures.
It is incontrovertible that we equate sentience with both
humanity and a right to humane treatment. Throughout history,
the worst cruelties perpetrated by humans upon each
other have often come about when the offenders persuade
themselves that their victims are not really human and not
really sentient. In the early 19th century, a famous advertisement
was placed in a British newspaper for ‘guns’ (i.e. men
with guns) to join a hunting expedition – to kill Tasmanian
aborigines. In 1800 there were about 5000 of these people
alive, but by 1867 they were all dead, reduced to a series of
body parts displayed in museums. This shameful genocide
was not considered as such by these ‘guns’ simply because the
Tasmanian aborigines were not considered, by them, to be
people.
Animals are not people, but then again if we are talking
about intellectual ability (and sentience) many people aren’t
really people either. The critically senile, accident and illness
is fido a zombie? 37
victims in comas, the newborn – all have intellectual capabilities
and sentience well below those of, say, an adult chimp or
Kola the gorilla, yet across all societies and cultures the human
will be granted far more rights under law than the ape.
As the Australian philosopher Peter Singer, who takes an
extreme but persuasive reductionist approach to animal
rights, argues, this is illogical. If it is right to take a chimp’s life
to save a human then it may also be right, under certain circumstances,
to take a human’s life to save a chimp. To argue
otherwise is simply wrong and makes one guilty of arbitrary
speciesism. The Great Ape project (the name of which, ironically,
indicates a certain amount of arbitrary speciesism itself)
is a loose group of scientists and philosophers which argues
that we should extend certain legal rights to at least the
‘higher’ primates, our closest cousins, as a first step. This
would mean that experimentation, for any purposes, even to
test potentially life-saving medical procedures, should be
banned on these animals, everywhere and in all circumstances.
The great apes would in fact have similar legal rights
in law as human beings.
If non-human primates can show evidence of metacognition
– thinking about thinking and reflecting upon memories –
that puts them in a wholly different light. They, and perhaps
many other species, can no longer be thought to live in an
eternal present, responding to hunger and pain, fear and pleasure
with no concept of anticipation or reflection. It is, perhaps,
one thing to cause pain to an animal which can neither
anticipate nor reflect on its experience, but quite another to
lead into a laboratory or abattoir a terrified creature which has
already created a distressing mental picture of what is about
to happen to it in its head.
Most people do not think like this of course. I know many
scientists who argue, persuasively, that granting an ape
‘rights’ over, say, an elderly person suffering from Parkinson’s
38 10 questions science can’t answer yet
Disease is ludicrous. By experimenting on the brains of monkeys
and apes scientists have made great strides in learning
how this most debilitating and terrifying of illnesses works,
and have taken steps towards finding a cure. Stopping this
experimentation, in labs in Europe and America, has become
the raison d’être of many animal rights organizations, some of
which have resorted to terrorism to get their point across, and
this we all agree is despicable.
And what about the ‘rights with responsibilities’ argument?
Again, many scientists and lay people say, it is ludicrous to
grant ‘rights’ to an animal that can have no concept of its
responsibilities under the laws that are giving it protection. If
we protect chimpanzees from vivisection, should we also not
be prosecuting chimps when they murder each other, or
indeed us (as happens)? Should gorillas get the vote? This is
ludicrous, clearly, so perhaps we should think again about
these ‘rights’ and dismiss the idea out of hand.
But actually the ‘responsibilities’ argument falls down very
quickly. Because we grant a whole host of rights to human
beings from whom we demand no responsibilities whatsoever.
Again, we are talking about the very young, the very old,
the sick, senile and the mad. Lunatics cannot vote and neither
can babies, but we are quite rightly not allowed to stick electrodes
into their brains in the advancement of medical science.
Young children are absolved from full responsibility
when they commit criminal acts. We have no problem in
granting humans rights without responsibilities, so why not
animals?
The best guess is that we will have to muddle through, perhaps
tightening the cruelty laws a little, but essentially maintaining
the same troubled relationship with the animal world
that has held sway ever since we diverged from our closest
relatives. But this state of affairs may not be able to continue
forever. The more we learn about the most intellectually
is fido a zombie? 39
advanced of the animals, the more squeamish we will inevitably
become. Every second humans kill some 16,000 animals
for food – that is 50 billion lives taken per year. While this
slaughter may be carried out in fairly humane conditions in
wealthy countries with strict laws governing farm animal welfare,
we can assume that the vast majority of these lives are
ended in a relatively disgusting and brutal way.
It may well be the case that in decades or centuries to come
we may look back upon the way we treat our fellow creatures
today with the same sort of revulsion with which we now treat
slavery – a practice which 250 years ago was widely accepted
in most of the ‘advanced’ societies on the planet. This is not an
argument for vegetarianism, but it is an argument for a lot
more compassion.
So, where does the science go from here? While behaviourism,
‘anti-mentalism’, is probably defunct as a philosophy,
behaviourist techniques have survived and the rigour of
behaviourist thinking is, ironically, exposing the mental life of
animals as never before. Scientists study – or try to study – animals
both in the laboratory and, increasingly, in their natural
environments as rigorously and methodically as if they were
conducting a double-blind drug trial. This is not easy. When
observing the behaviour of an animal as complex as the chimpanzee,
for instance, over long periods, it is probably asking
too much of even the most diligent human researcher to avoid
drawing all sorts of emotional inferences about their subject
matter.
The harsh truth is that highly intelligent animals are often
extremely endearing and form close emotional bonds with
their observers. But this doesn’t mean that the extraordinary
fieldwork such as that conducted by Jane Goodall with ‘her’
chimpanzees has not added hugely to our knowledge of these
extraordinary animals. More and more ethologists want to
study the cognitive abilities of apes and cetaceans, animals
40 10 questions science can’t answer yet
too large, demanding and expensive to observe in any numbers
until quite recently. Controversially, some scientists have
tried to push animal cognitive abilities to the limit – trying to
teach chimps sign language, for example.
Clever new techniques have been used to unlock the animal
mind. The Gallup mirror test, while imperfect and probably
not definitive, is giving us startling new insights into animal
consciousness. It is now considered that what may be a defining
characteristic of true sentience – a theory of mind, or
‘knowing what the other guy is thinking’ – is possessed by at
least some primates. Finally, there has been the growing cultural
awareness of what science has known since the 19th century:
that humans are animals. The biochemical, neurological
and evolutionary relationships that led to our minds and the
minds of other species are now being mapped. Hardly anything
now is considered to be definitely, absolutely, ‘unique’
to humans. Intelligence, tool use, language, fear, jealousy and
anger have all been observed in many species.
Chimpanzees have been observed engaging in behaviour
that it is hard to interpret as anything but extremely violent,
vindictive and even sadistic. Even the humble rat has been
found to be alarmingly ‘humanlike’ in many of its traits,
displaying signs of affection, bloody-mindedness and even
addiction to various narcotics (it is quite easy to make many
animals alcoholics, nicotine addicts or even persistent and
enthusiastic users of cocaine). While many animals may mirror
‘our’ finer cognitive traits, they are not immune to our baser
ones either. The old line about it being unfair to compare
thuggish people to animals because ‘animals never stoop
that low’ is not correct. In essence, the study of animals’ brains
has become more like the study of human brains and vice
versa.
This remains a hugely controversial field. Behaviourist thinking
survives, and acts as a useful antidote to those who see
is fido a zombie? 41
evidence of profundity every time a dog barks or a whale flips
its tail. The attempts to teach animals to ‘talk’, or at least sign,
look, say sceptics, far more impressive in TV documentaries
than in the cold hard light of laboratory trials. Perhaps inevitably,
this is a field which attracts flaky thinking like moths to a
candle – to some, it is only a short step from talking parrots to
telepathic parrots.
We may no longer be alone, and this will, inevitably, affect
the way we treat our fellow consciousnesses. Hurting a
zombie is fine because the zombie cannot mind. But how
many scientists now believe that even their rats are zombies?
For the moment the mainstream scientific establishment considers
that it is, just about, OK in extreme circumstances to
experiment on a chimpanzee. Will this still be the case if the
chimpanzee asks us to stop?
References
1 Plotnik, J., de Waal, F. B. M. and Reiss, D. (2006) Self-recognition
in an Asian Elephant. Proceedings of the National Academy of Sciences,
103(45), 17053–7.
2 Weir, A. A. S., Chappell, J. and Kacelnik, A. (2002) Shaping of
hooks in New Caledonian crows. Science, 297, 981.
3 Emery, N. J. and Clayton, N. S. (2004) The mentality of crows:
convergent evolution of intelligence in corvids and apes. Science,
306, 1903–7.
42 10 questions science can’t answer yet
2
why is time so weird?
43
Time makes our lives. It is the key to how we perceive everything,
from the ticking of our own minds to the events which
mark our passage from birth to death. We can perhaps imagine
a universe without colour, or without heat or light, but we
cannot imagine a world without time. And yet, as far as physics
seems to understand it, we may have to.
When it was assumed that base metals could be turned into
gold, it was naturally assumed that there must be a substance
which could effect this. Now, like the old philosopher’s stone,
we assume that there is a ‘quantity’ which marks the passage
of events. Just as space stops everything happening in the
same place, time stops it all happening at once. But while we
know space is there – look, I can wave my hands through it
right now – time is qualitatively different. We cannot, after all,
wave our hands through time.
The true nature of time continues to elude us. Physicists
have made huge strides in the last century or so in the way
we think about time, but as to what it is exactly we are not
really any wiser than the Ancient Greeks. Plato, after all,
thought time was an illusion, and his view seems to be
coming back into fashion. As the mathematical physicist Paul
Davies says, ‘Nothing in known physics corresponds to the
passage of time... how can something so basic to our experience
of the physical world turn out to be a case of mistaken
identity?’.
We talk of time ‘flowing’, but flowing through what? At
what speed does it flow and why? And what is the ‘substance’
that flows? A spacecraft moves through space and its motion
can be described relative to other objects. But the passage of
time cannot be described with reference to anything other
than itself.
We can think of time in terms of mathematics and physics,
and we can also think of it in terms of perception. The way we
think about time seems to be linked in a rather odd way to the
44 10 questions science can’t answer yet
way we think. We do not really ‘see’ the passage of time, after
all. We simply have a series of subjective experiences that are
different from the ones in our memories and it is this difference
that our conscious brains perceive as time.
Time throws up all sorts of paradoxes. You can use the existence
of time, for a start, to prove that nothing is real. The past
is as dead as those who no longer live, no more real than your
dreams, right? And the future has not happened yet. So all
that is to come is, again, imagination. All that is real, therefore,
is that infinitesimal sliver of time between past and present,
which of course amounts to nothing, because as time never
stops that sliver has zero thickness. So, time is real, but nothing
else is.
Since Einstein, many physicists have tried to break away
from the traditional, common-sense view, or presentism, i.e.
the view that it is only the present, the world at the moment
‘now’, that exists. New ideas about time recast this slippery
quantity and try to remove the subjective perception of time
by human brains from the equation, as the presentist view of
time is increasingly at odds with the way physicists believe the
world to be.
?
What science has always been happy to do with time is to
ignore the philosophical horrors it throws up and just get on
with measuring it, giving it a symbol and plugging it into our
equations, represented by a nice little letter, like t, doing its
job, oiling the clockwork of the spheres. Time is a fundamental
quantity, meaning that it cannot be defined by reference to
any other quantity. We can only measure it and use time to
why is time so weird? 45
derive less fundamental quantities. A change in velocity over
time gives us acceleration. If you drop a pebble down the well,
you can calculate the depth in metres simply by multiplying
the square of the time, in seconds, before you hear the splash
by five (if this is Earth you are talking about).
Einstein showed us that the pull of gravity and the tug of
acceleration were equivalent (the force you feel in an accelerating
rocket is exactly the same as the force you feel as your
weight is pulled towards the Earth). Indeed, Einstein went on
to show that ‘space’ and ‘time’ are really different sides of the
same coin. Before Einstein, it was thought that space was filled
with an invisible medium called the ether, waves in which carried
light and other electromagnetic radiation just as air carries
sound. All that was needed was to work out the properties
of the ether, particularly how it deformed and responded to
the input of energy, and physics would be solved.
But the idea of ether had to be abandoned when it was
found (in 1887 by Albert Michelson and Edward Morley) that
the speed of light, as measured by an observer, is the same
regardless of of the speed of that obsever relative to the source
of the lightbeam. Later, the Irish physicist George FitzGerald
and the Dutchman Hendrik Lorentz suggested that this could
be explained if you assumed that time actually ran more
slowly in moving objects, meaning that light would appear to
travel at the same speed for everyone. But they still assumed
that this movement was relative to an ether.
But in Einstein’s relativity, the old ether was abolished and
replaced by space–time, a sort of conceptual super-ether,
through which motion and the attracting force of gravity can
be plotted. Because it was impossible to measure one’s
velocity relative to the ether (the old ether) then the whole
notion was flawed. Instead, we all have our own personal time
(in fact each independently moving point in space–time has
its own personal time; my left foot’s is slightly different from
46 10 questions science can’t answer yet
that of my head). If you take Einstein’s ideas about time to
their logical conclusion (as indeed he did) you must throw
away all ideas about ‘rivers’ and indeed of pasts, presents and
futures. Plato would have approved.
One can plot an object’s movements through space–time as
one can through the three spatial dimensions. For example,
you can represent the orbiting of the Moon around the Earth
as a helix, with time forming the vertical axis. Physics sees time
very much as a ‘label’, a way of thinking about events, and
especially the relationship with events that can be described
mathematically. A point, for instance, occurs in both space
and time. If you take two points, P1 and P2, they can have a
series of different relationships, spatially and temporally, to
each other. But their spatial relationship is qualitatively very
different from their temporal one.
If P1 occurs before P2, for instance, then P1 can affect P2.
But P2 does not have the same relationship with P1. You can
talk about the ‘causal future’ of P1 in other words in the
same way that you are not able to talk about the ‘causal
past’ of P2 – simply because (in our Universe) events do not
have ‘causal pasts’. Einsteinian space–time in fact delineates
the geometry of both space and the order of events. From
any occurrence, the effects of that occurrence throughout
subsequent time form a ‘cone’, extending into the fourth,
temporal, dimension.Within the cone, all is causal and logical.
Without, causality is lost and madness reigns. This ordering,
the idea that time is a way of saying that one thing follows
another as a result of the other, seems to be the key to time’s
true nature.
Einstein made us throw away any idea of absolute simultaneity.
Two events which occur at the ‘same time’ in one reference
frame may occur at different times when viewed from
another. The question ‘What is happening on the Moon right
now?’ actually has no meaningful answer. Someone on Earth
why is time so weird? 47
is always a second and a half away from being able to know
anything about what is happening on the Moon, as no information
can travel faster than light. As there is no absolute,
privileged ‘now’, it’s better instead to think of a ‘timescape’
where time is laid out in its entirety.
The way in which time works seems to run counter to the
way just about everything else in physics works. For instance,
impulses can be reversed: objects slow down and speed up.
For most things, there is no arrow, no one-way street. Processes
are symmetrical. But time-dependent processes are different.
If you drop a glass on the floor and it breaks, the pieces
do not – and will never – make themselves back into a new
glass again. Entropy, the degree of disorder in a system, will
tend to increase over time (the second law of thermodynamics).
The ‘one-wayness’ of time is proving a real headache for
physicists. It is quite probable that we will need to discover a
lot more about time before quantum physics and relativity can
be reconciled into a theory of everything.
Unlike quantum effects, time is something we perceive
directly. We have memories of the past but not of the future.
Neither the future nor the past are ‘real’ in the sense that they
are accessible and measurable, but one seems to have a privileged
position over the other: the fact the past has ‘happened’
gives it a reality denied the future. The Big Bang seems to have
imposed a cosmological arrow of time. The galaxies (or rather
superclusters of galaxies) have been flying apart for around
13.7 billion years and there is now no reason to suppose this
situation will ever reverse itself.
Perhaps the opposite extreme from thinking of time as nonexistent
is to treat it as a fundamental – perhaps the fundamental
– component of the Universe. A theory called loop
quantum gravity, one of the attempts made to resolve the differences
between quantum theory and relativity, suggests
that fundamental particles may be composed of tiny rolled-up
48 10 questions science can’t answer yet
braids of space–time. It is an attractive concept – at the heart
of it all is just space and time, no ‘stuff’ at all. In the words of
science writer Davide Castelvecchi, ‘if electrons and quarks –
and thus atoms and people – are a consequence of the way
space–time tangles up upon itself, we could be nothing more
than a bundle of stubborn dreadlocks in space’.
The trouble is that, pretty though this idea may be, like
string theory it is very hard to test experimentally. To detect
strings we may need to build particle accelerators the size of a
continent in order to generate the necessary energies.
To probe the internal structure of these strings we would
probably need to start building planet-sized atom-smashers in
space. Since it is a fair bet that NASA’s or CERN’s budget will
not run to this any time soon, we have to rely on theory
coming up with the goods. That or perhaps – just perhaps –
getting lucky and detecting what some physicists think may
be remnants of the colossal energies of the Big Bang: cosmic
superstrings, giant expanded subatomic particles billions of
miles long made of ‘stuff’ so dense that a metre of superstring
would weigh trillions of tonnes.
?
Time as a fundamental quantity seems to be intrinsically
linked to our conscious perception of the world. The philosopher
Derek Parfit, in his seminal 1986 book on personal identity,
Reasons and Persons, wrote of ‘the objectivity of temporal
becoming’. Time is, he says, linked intimately and extremely
weirdly to our notion of continuous personal identity, something
to which most of us give little thought, although it is
perhaps the key aspect of our existence.
why is time so weird? 49
The idea that time is just the fourth dimension of space, one
which we have a special interaction with through the offices of
our conscious minds, is an attractive one. And clearly there is
an element of truth in it. It is impossible, as H. G. Wells’s Time
Traveller said, to have an ‘instantaneous cube’. One cannot
exist for an infinitesimal amount of time.
The nature of time does seem to be very tied up with the
way we perceive it. The Universe that we perceive is, in
the most fundamental way, the creation of our sensory
apparatus. When you touch a wooden table top with your
fingertips you are actually ‘feeling’ the tiny repulsive forces
of trillions and trillions of electrons; you are not actually
‘touching’ anything at all. When you ‘see’ objects you
are simply making sense of reflected and emitted photons
which your brain has, in a probably rather arbitrary and
contingent way, evolved to interpret as light and dark,
colours and so on.
It is the same with time. The strange and elastic nature of
perceived time is well illustrated by a quote from Albert Einstein:
‘When a man sits with a pretty girl for an hour, it seems
like a minute. But let him sit on a hot stove for a minute and it’s
longer than any hour. That’s relativity’.
This quote is lifted from the abstract for a short article Einstein
wrote for the Journal of Exothermic Science and Technology
in 1938 (he went on to detail the difficulties of obtaining a hot
stove and a pretty girl – ‘I live in New Jersey’). Many people
have remarked that time can sometimes appear to flow at dramatically
different rates from ‘normal’. For example, it is
common to report that time dramatically ‘slows down’ just
before an impending disaster, such as a car collision or being
thrown off a horse.
Professor David Eagleman, a neurobiologist at the University
of Texas Medical School, devotes his research to the perception
of time. He illustrates a very fundamental anomaly with
50 10 questions science can’t answer yet
the ‘flash-bang’ phenomenon. Sprint races are started by a
bang rather than by a flash because our brains (or at least the
unconscious motor-response bits of our brains that sprinters
rely on to get them off the blocks) respond to sound faster
than they do to light (even though sound travels to our ears at
only a millionth of the velocity of light waves).
When it comes to perception the conscious parts of our
brains perform a very clever editing trick to make sure that we
think sound and light travel at the same speed. If you click
your fingers in front of your head, you perceive three things as
happening simultaneously: the noise of the click, the sight of
your fingers clicking and, most weirdly, the actual decision to
click them right at that point. In fact, these events all happened
at different times.
You ‘decided’ to click your fingers several tens of milliseconds
before the nerve impulses were sent down your arm to
enable the muscles to do so. The sound of the click arrived
at your brain an instant behind the light. These are tiny
amounts of time, but our brains are capable, if that is what
we want them to do, of perceiving extremely small time
intervals, of the order of hundredths or even thousandths of
a second.
It is quite possible to trick the brain’s temporal editing suite
into mixing up time altogether. In an experiment published in
2006, Professor Eagleman set up an experiment in which volunteers
were told to press a button1. When the button was
pressed the light would come on almost instantaneously as a
result. At other times, they were asked to press the button
after the light came on. In all cases the subjects were able to
distinguish perfectly the order of events.
Then, the experiment changed. There was now a 100 millisecond
delay (an easily perceived time interval) between
pressing the button and the light coming on. But after pressing
the button a few dozen times, the brains of the volunteers
why is time so weird? 51
recalibrated the time delay back down to almost zero. But
now comes the interesting bit. The time delay was changed
from 100 milliseconds to 50 milliseconds. What happened
now was unexpected. In some cases, the subjects perceived
that the light came on before they pressed the button. In other
words, their brains had been tricked not only into
misperceiving the order of events, but misperceiving causality
as well.
One of the most unsettling experimental results in the
history of science was the study by neuroscientist Benjamin
Libet. He monitored brain and nerve impulses to show that
the movement of muscles under supposedly conscious control
– the tapping of a finger, for example – is governed by nervous
impulses from the brain and spinal cord before we become
aware of wanting to move. This is disquieting, as it strongly
implies that our sense that we are in conscious control of our
actions is an illusion.
In fact, our perception of time shows us something quite
interesting about consciousness and free will. We neither
decide to act then act, nor predict that we will decide to act
then act, but instead construct a post hoc fiction that ‘we’,
meaning our conscious minds, made a decision.
And time perception is a key part of all this. Eagleman says: ‘I
often wonder what, if we could work out what was really
going on in reality, and we were able to take time out of the
equation – that little t embedded in so many physics equations
– would this have an emotional effect?’.
So much of our emotional lives is tied up with a very singular
perception of time. Grief, loss, apprehension and anticipation
are all tied up with an internal model of time and causality.
Einstein wrote to the sister of his deceased friend Michel
Besso: ‘That Michel has preceded me from this strange world
is not important. For us physicists the distinction between
past, present and future is an illusion’.
52 10 questions science can’t answer yet
When someone dies we think of them as irretrievably lost,
yet they existed for long enough to have made an impression
on our consciousness – enough for us to miss them. You do
not grieve for children before they are born, yet the Universe a
week before the birth of an infant is as bereft of that person as
the one a week after they die, 80 years hence. Time in this way
has such a close relationship to our experience of it that this,
perhaps, sets it apart from all other physical quantities.
In fact, it is quite easy to imagine a way of living that perceives
time in a very different way from the way in which we
humans see it. We cannot see into the future – that seems to
be forbidden – but we can certainly see into the past. We live
in the present – that is the way we have evolved and it clearly
works best for us. But imagine if you were a creature for whom
the past was equally ‘real’ to what was happening now. Events
that happened a day, a month or a decade ago would be just
as real as events that are happening now. Of course we do
operate a bit like this – we live constantly not in the true now
but in the now of a few seconds or milliseconds ago. It takes
time for us to catch up with time. But for us the past is dead.
If it were not then we would have a very different view of the
Universe. Death, for instance, would lose its impact somewhat.
If the lives of those we had lost were as real as the lives of
those still with us, would we mourn the dead like we do?
Derek Parfit wrote that it would perhaps be better for us if
we were ‘timeless’, treating both past and future with equal
weight. Then, we would not, it is true, be relieved when a bad
thing is over, but neither would we be sad when a good thing
is past.We would, in a real sense, be cheating time. For a timeless
person, ten hours of agony yesterday is as bad as ten hours
tomorrow. But for him, death also holds no more fears than
birth.
Curiously, we seem to be better at taking a timeless view of
others; suppose we are told that a close friend who lives
why is time so weird? 53
abroad is very ill and is dying. We hear they face three
months of misery before the end is predicted to come. Then
we hear that there was a mix-up. The friend was ill, but that
was some time ago. There was indeed threemonths of suffering
but the friend is now dead. Do we feel better about this?
No – which is perhaps strange, as we would feel better if we
were told our own suffering was over and not yet to come.
Because it is our friend we are unhappy at the idea of their
distress, whenever it happens. We are able to treat our
friend’s past, present and future with rather more objectivity
than we do our own lives.
‘In our everyday experience’, writes Piet Hut2, a physicist at
the Institute for Advanced Study at Princeton, ‘time flows, as
we flow with it. In classical physics time is frozen as part of a
frozen space–time picture. And yet there is as yet no agreedupon
interpretation of time in quantum mechanics. What if a
future scientific understanding of time were to show all previous
pictures to be wrong and demonstrate that the past, the
future and even the present do not exist?’.
Causality, the key to time, seems to be something hardwired
into our brains. As Toby Wiseman, a physicist at Imperial
College London puts it, ‘maybe deep within our brains
we have this notion of cause and effect. Maybe no physicist
could come up with a theory where causality didn’t work
that way’.
The idea of ‘block time’, an Einsteinian or Platonic time landscape
where past, present and future are all equally real, is
popular amongst physicists as it discards the apparent subjectivity
of the passage of time. Nevertheless, the idea that the
future has, in a sense, already happened and that we should
no more fear our death than our birth runs so counter to our
commonsense view of the way things are that it will probably
never be accepted as folk science. It is an intriguing thought
that if we could break away from our presentist view, then
54 10 questions science can’t answer yet
maybe we would be a lot happier. We would lose both fear
and regret. We would also lose anticipation. So there would
be a price to pay for being timeless.
It is certainly hard to imagine a universe where time worked
in a radically different way from the one we are used to. All
sorts of alternative universes have been postulated – ones
where the gravitational constant is different, or where the
weak and strong nuclear forces have different values from
those in our Universe. Most of these universes would be very
different places and ones very challenging to life. It seems to
be the case that if you change the physical parameters even by
a bit you end up with a universe that is either a massive black
hole or a boring sea of elementary particles.
At least these alternative universes are respectable and polite
entities, albeit rather dull and unexciting ones. But there is one
constant that you cannot change, and that is causality. If you
muck around with the order of events you end up with a very
badly behaved universe indeed. Space, mass, the forces and
the menagerie of particles are all essential parts of the recipe of
being. But time, it seems, even if we are not very sure what it
is, really is of the essence.
References
1 Stetson, C., Cui, X., Montague, P. R. and Eagleman, D. M. (2006)
Motor-sensory recalibration leads to an illusory reversal of action
and sensation. Neuron, 51(5), 651–9.
2 Hut, P. (2006) A radical re-evaluation of the character of time.
In What Is Your Dangerous Idea? (ed. J. Brockman). Simon &
Schuster, New York.
why is time so weird? 55
3
can i live forever please?
56
Ageing is as inevitable as the sunrise and taxes, right? Well,
yes, if you are unlucky enough to be born as a human. We get
made, we live our lives, we wear out, we croak. It’s sad and
depressing and there is not much we can do about it, so we
might as well get used to it. ‘I don’t want to achieve immortality
through my work’, Woody Allen once said. ‘I want to
achieve it through not dying’.
Someone who thought very much along the same lines was
the late Professor Roy Walford, a biologist at the University of
California Los Angeles. Walford believed he had discovered
the secret, if not of immortality, then certainly of the key to a
much extended lifespan. According to Walford, the secret to
life extension was to eat less. Actually, to eat almost nothing.
I visited him once, back in 1999, at his house in Venice
Beach. At the time he was in his early 70s and had the general
demeanour of an elderly Hell’s Angel rather than of a respected
academic: elaborate facial hair, bald pate, denim shirt,
medallion (I think) and an unexplained pair of attractive
women scuttling through the house. We sat down and he
explained his philosophy.
‘I think I can get by on less than a thousand calories a day’,
he said. Walford was the world’s leading proponent of calorie
restriction as a way of extending life. He wrote some popular
books (The 120 Year Diet, Beyond the 120 Year Diet: How to
Double Your Vital Years) and set up a web site, and a sort of
online club came into being, a low-cal community that followed
Walford’s dietary advice. ‘Please forgive me if I eat’, he
said, and his ‘supper’ was brought, a bowl of rice and some
water. ‘Don’t you lose the will to live, eating like this?’, I asked
him. ‘Nope. The more I eat like this the more I’ll live and that’s
that’, he replied. After I finished the interview I went off and
searched out a pizza.
A couple of days later I ran into Greg Stock, a UCLA biologist
colleague of Walford’s and another scientist who thinks it may
can i live forever please? 57
be possible to do something about ageing. As we sat down to
tea and cakes in the UCLA refectory (Stock is no calorie
restrictor), he told me about his plan to organize a big cash
prize for anyone who came up with a concrete way to extend
human lifespan. The prize remains unclaimed. Just before we
parted he asked me how Walford seemed. ‘He’s amazing’,
Stock quipped. ‘Must be 72, 73... and doesn’t look a day over
80!’ Walford died in 2006. Woody Allen is still very much with
us, but sadly we have no reason to assume his wish will be
granted any more than it was for Walford.
Ageing is a very odd subject. Like the nature of time it is
something we still have not entirely come to grips with. Like
the nature, and disputed existence, of animal sentience it is
political and hugely controversial. There is a lot of work
being done about the nature of the ageing process, but
rather less on doing anything about it. Combatting ageing is
one of those areas where there is a huge, yawning chasm
between public perception and desire, and what scientists
are actually doing and prepared to contemplate. Anyone
who suggests they have found a way to extend human lifespan
is usually dismissed out of hand as a nutter. This is not
surprising, as to date date the field of life extension has been
liberally peppered with the eccentric and insane. Perhaps
more surprising is the opprobrium heaped upon anyone who
even wishes itwere possible to make us live longer. There are
a few scientists of ageing – biogerontologists – out there who
regard ageing as a ‘disease’ and therefore, at least in principle,
curable. But these people are not popular in the scientific
community. There is a paradox here. Death is not popular.
Yet we don’t seem to have much of a will to do anything
about it, even in the scientific community, which possibly
could. This is odd.
How long you are likely to live varies hugely among species.
It might have been better for both Walford and Allen to have
58 10 questions science can’t answer yet
been born, say, tortoises, which have been reliably recorded
to reach nearly 200 years. Or better still, a whale. Whales are
brighter than tortoises (although we don’t know if they have a
sense of humour). Mariners used to tell tall tales of the great
cetaceans reaching incredible ages – 150, 200 years and
more. These stories were until recently dismissed as tall
beyond belief. But bowhead whales have been found recently
with antique harpoons embedded in their skulls – weapons
dating from the 1790s. It is therefore possible that there are
large sentient animals alive today that are older than the US.
Georgian whales: extraordinary. Some deep-ocean fish have
been found that may live well into their second century. The
Orange Roughy, a species now popular as food (it was previously
known by the less-appetising name of ‘Slimehead’) does
not mature until its mid-30s, and the individual on your plate
may have been swimming in the Pacific when Lincoln was in
the White House.
There are some suggestions that some of the very large dinosaurs
may have been, if not immortal, then true Methuselahs,
even compared to today’s longest-lived whales, tortoises and
fish. The great sauropods, some of which may have been 200
feet (65 metres) long, were probably immune (once they
reached adulthood) to any predators, and infectious diseases
and cancers may have progressed very slowly. It is not wholly
impossible that some of these great animals lived a thousand
years or more. Some sea anemones and molluscs appear to be
effectively immortal, in the sense that they do not weaken and
succumb to diseases of ageing, but how long actual individual
animals can live in the wild is moot. To do better than this you
need to leap out of the animal kingdom.
The bristlecone pine is one of the regular attractions in
Guinness World Records. One specimen, alive and well-ish in
California, is 4844 years old (as determined by counting the
rings in its trunk). Several trees have maximum lifespans of a
can i live forever please? 59
thousand years or more, including the giant sequoias. This is
hugely impressive, but the true record holder is several orders
of magnitude more impressive again. In 1999, some bacterial
spores were successfully revived in a laboratory. These specks
of life had been found encased in salt crystals in a cave in
Carlsbad, New Mexico. Nothing strange about that – except
that the spores were estimated to date from a quarter of a billion
years ago. That means there are bacteria alive today that
predate the first dinosaurs.
At the other end of the scale life can indeed be short. Some
insects (mayflies are the most famous examples) have adult
stages that last but a day or two (although their total life
cycle is rather longer). Small mammals – mice, shrews and so
on – are lucky to make two years. Birds tend to do rather
better, as do bats. Humans come in near the top end of the
scale, with the oldest recorded person to date, the magnificent
Jeanne Calment, reaching a scarcely credible 122 years
and 164 days. Mme Calment was French, and thus took little
heed of a ‘healthy lifestyle’. Indeed she smoked well into her
90s and ate and drank pretty much what she wanted. It is
possible that there have been older people, but not many.
Tales of remote mountain folk living to fantastical ages are
just myths – the one thing all these places have in common is
that the registrar for births, marriages and deaths is an infrequent
visitor.
So what does all this tell us? Do, for instance, ageing and
death come to us all? Those whales and tortoises die eventually,
sure, but what about those bacteria? Two hundred and
fifty million years is an extraordinary amount of time for an
object as complex as a living cell (complete with genetic
material) to be preserved (there is some controversy as to
whether the revived bacteria were still capable of respiration
and division). The existence of these objects shows that true
immortality is probably not unattainable.
60 10 questions science can’t answer yet
There is a great deal of variation in lifespan, and it is not
always clear that there is a pattern. Generally big things tend
to live longer than small things – this goes for plants as well as
animals. Mice and the like live a couple of years; insects far
less; dogs, rabbits and cats rather more. Fish, unexpectedly
perhaps, live quite a long time. Even the little goldfish can live
to nearly 50. Large mammals and reptiles do well – elephants
can live into their 70s and humans, as we have seen, well into
their 100s, although our great ape relatives are lucky to reach
three score. Horses and cattle, despite their size, do badly. And
bats and birds, despite theirs, do very well.
And slow things tend to live longer than fast ones. Those
long-lived deep-ocean fish lead sluggish, almost catatonic,
lives compared to their frisky near-surface cousins. If you hold
a shrew in your hand its heart beats so fast it almost vibrates.
Big animals, like whales and elephants, have a much slower
metabolism. There is some truth to the old idea that while
lifespans of different species may vary wildly, the number of
heartbeats in an animal’s life tends to be about the same.
When it comes to human ageing there are more patterns.
Generally we have been living longer and longer as time has
passed, but it is not clear that this has always been the case. A
strange misunderstanding has grown up, by the way, concerning
the term ‘average life expectancy’ and what this really
means. For instance, in Ancient Rome the average life span of
a citizen was less than 25. This has led many people to suppose
that people in their 20s and 30s were ‘elderly’. I have
heard TV commentators asserting that in African countries
today, where life expectancies may be in the 40s or less,
people in their 30s are ‘old’.
Of course people in Ancient Rome did not consider themselves
‘old’ in their 20s, no more than Africans aged 35 do
today. An old man then, as now, was someone with grey hair
and a grey beard with at least five decades behind him. These
can i live forever please? 61
frighteningly low life expectancies had very little to do with
ageing and everything to do with the ghastly levels of infant
mortality in most pre-modern societies. If three babies out of
five die before their first birthday, the survivors could all reach
100 and ‘average life expectancy’ will still be only 40. If you
strip infant mortality out of the equation (by working out life
expectancy aged five, say) children in classical times could
probably expect to live into their 50s or 60s, and many into
their 80s and beyond.
Most of the advances in life expectancy in recent centuries
have been down to reducing infant mortality rates. Clean
water, an understanding of sanitation and diet, and in particular
inoculation and vaccination have, in the past 150 years or
so, effectively doubled the amount of time a wealthy First
World human can expect to live on emergence from the
womb. A few decades ago it was assumed that life expectancy
in developed countries would reach some sort of plateau
around now, but that has not happened. In fact, in the world’s
wealthiest nations, average life expectancy continues to increase
at around two years per decade – which means that in
the richest countries, every day pushes up life expectancy by
five hours.
What is rather less well known is that until the advent of all
these wonderful new technologies, human life expectancy
had probably been dropping steadily over the past thousand
years despite – or rather because of – the vast advances in
technology and in particular agriculture made by Homo sapiens
since the last glaciation. It is now believed that our Stone
Age ancestors may have enjoyed rather longer lives, even
taking into account infant mortality, than, for example,
mediæval Europeans. (They were rather taller, too.)
There is some evidence that in today’s poorest countries
those people maintaining a traditional hunter–gatherer lifestyle
tend to do rather better than those at the bottom of the
62 10 questions science can’t answer yet
agricultural heap, and there is good reason to suppose that
with the advent of agriculture and the specialization of industry
the general health of the population went down, as the
price we paid for an increase in the number of people that a
given parcel of land was able to sustain.
Our diets became blander and less nutritious, we introduced
more refinement to our food (milled grains) and, in particular,
by living in larger, fixed communities, we became much more
susceptible to epidemics of infectious diseases. It wasn’t until
the advances in sanitation and understanding of how diseases
spread that the ‘wealth’ allowed by the Great Leap Forward
into agriculture some 10,000 years ago paid the dividend of a
healthier, as well as a larger, population.
In some other ways we are still going backwards. In the
‘Stone Age’, a loose term which I am using here to indicate
any pre-agricultural civilization, humans may not have been
very long-lived and may well have been constantly on the
verge of starvation, but they were superbly fit. Most of today’s
remaining hunter–gatherers are quite happy covering 30 to
50 kilometres a day, running or walking on foot. Hunting, and
even the gathering of shellfish and berries, was and is an
intensely physical activity. The average Palaeolithic European
or Neanderthal probably expended twice the calories per day
in exercise as the average Roman citizen, and the average
Roman three or four times as much again as we do today. It is
interesting to speculate what our lives, health and life expectancy
would be like if we could combine a Palaeolithic
hunter–gatherer lifestyle with all the advances of modern
medicine and sanitation. One suspects that we might well see
a substantial jump in life expectancy.
It is quite easy to see how we could increase life expectancy,
but it is not at all easy to see how we could increase our maximum
lifespan. This seems to be set at something around 120
years. Even the healthiest populations, shielded from epidemcan
i live forever please? 63
ics and violence, made up of people with the resources to eat
well and take advantage of medical care, seem to be unable to
produce more than a handful of ‘supercentenarians’: those
who live to 110 or more. To date, the world has seen some
800 documented examples.
Compare to this the near one million ordinary centenarians
in the record books. While it is certainly becoming much
easier to live to be a hundred (in the 1960s there were on average
only about 300 centenarians alive in the UK; forty years
later the figure is around 6,000 and by the late 2030s the prediction
is that this will increase tenfold again – in a population
that is relatively stable), it does not seem to be any easier to
live to 112. In 1857, there was one 112-year-old alive in the
world, a Dutchman called Thomas Peters, who died that year.
Today, there are about a dozen or so people alive at that age
or above, but between the 1850s and now the figure has at
times been higher. Since Jeanne Calment died in 1997 no one
has broken the 120 barrier. It is quite possible – even probable
– that, barring some fairly profound medical advances, I will
not live to see someone break her record.
Why? What sets this upper limit and what purpose does it
serve for a species to have a fixed maximum lifespan? To
understand this it seems we need to understand what ageing
is and how it occurs.
Ageing is a process shrouded in misconceptions. Many
people seem to think that, like machines, we simply wear out.
As to the deeper ‘Why?’, answers usually involve stuff like ‘for
the good of the species’ and ‘to make way for the young’.
It would be tempting to think of the human or animal body
like this, but it would be wrong. Yes, bits of us wear out as we
get older, just as bits of cars wear out as they get older, but
there are fundamental differences between the ways in which
the passage of time affects an organism and a machine. For
the first few years of our lives it is not clear that we actually
64 10 questions science can’t answer yet
‘age’ at all. Thanks to our huge brains, human infants have to
be born effectively prematurely; otherwise their mothers
simply would not be able to deliver them. Compared to the
young of virtually all other mammalian species, human babies
are extraordinarily helpless. For the first few years of our lives,
time tempers, not ravages, our bodies. Bones grow thicker
and stronger, as do muscles, tendons and cartilage. Our brains
become sharper, we discover the joys of locomotion, solid
food and language, and we develop a finely tuned immune
system. For the first 20 years or so of our lives we actually ‘antiage’
– in real terms, from babyhood to our late teens we get,
effectively, younger – our muscles get stronger, our skeleton
strengthens, our immune systems become more powerful,
we become sexually mature, our skin tightens and our hair
becomes thick and lustrous.
Sometime in our late teens or early 20s, things start to
go downhill. Ageing, or senescence, is loosely defined by a
declining ability to deal with stress. The body’s repair mechanisms,
including resistance to infectious disease, become less
efficient. This isn’t because ‘wearing out’ is the inevitable
result of the exposure of a living organism to time – see what
happens to us in early life – so there must be some other
reason for our bodies to give up on keeping us young.
One way of looking at an ‘explanation’ for ageing, or at least
an explanation for why different species age at different rates,
is to consider it in an evolutionary context. We age at a rate
determined by how long we could expect to survive in the
wild. Big animals tend to age slower than small ones simply
because, being big, they are less likely to be eaten, killed in an
accident, die quickly of starvation, or perish through cold.
There is no point in us having evolved an efficient mechanism
for dealing with cancers in our 90s, as our ancestors would
most likely have been in the stomach of a sabre-toothed tiger
by then.
can i live forever please? 65
An elephant will live perhaps 20 times longer than a mouse.
Mice in turn are much longer-lived than ants. The ageing–size
‘rule’ cuts across phyla and order. Big reptiles live longer than
small ones; ditto fish and amphibians. It is the interesting
exceptions to this life expectancy–size correlation that prove
the rule. Mice are short-lived, but bats (also small mammals)
live a relatively long time. Most birds live far longer than one
would expect given their size and weight. Tortoises (even
small ones) live a long time, and large tortoises may be among
the longest-lived animals of all. This can be explained simply.
Creatures that can fly, or which have body armour, are far less
likely to be eaten in any given time than creatures which do
not. And being eaten is a major – often the major – cause of
mortality in small animals.
It makes little sense for a mouse to be equipped with (perhaps
expensive) repair mechanisms for its body and the DNA
within if the chances are that it will be owl food within a year
or two. Better throw everything into making the mouse grow
up as quickly as possible and reproduce as effectively and rapidly
as possible in the short time that will inevitably be available.
Elephants are far less likely to be eaten than mice, so it
makes sense for their bodies to allow them the luxury of an old
age in which they can rear several generations of young. They
live slow, and die old. Like us.
The evolutionary theory of ageing leads to the nice aphorism,
‘death is the price we pay for sex’. By throwing all its eggs, so to
speak, in the basket of reproduction quickly enough to get a
chance of passing on its genes, the body pays the price later on
in the shape of cancers and other diseases of old age. The idea is
that the very sex hormones which endow our genes with
immortality hasten the extinguishing of the temporary ark in
which they are carried from one generation to the next.
Maybe the evolutionary theory of senescence explains
something about why we age but not how – nor what ageing
66 10 questions science can’t answer yet
really is. Evolutionists surmise that polar bears are white
because that is the only colour to be if you want to sneak up
on dinner in the Arctic. But this doesn’t tell us what makes a
polar bear white – to answer this more basic (and in this case
more straightforward) question, you need to catch one and
look at its fur, how the follicles are constructed, how these
refract and reflect light and so on. But if you speak to gerontologists
you are left with the feeling that there is nothing simple
at all about the how of the ageing process; in fact, that there is
a big hole in the middle of what we understand about ageing
– what makes the fur white, not why it is white (although they
will usually not put it in these terms and indeed will deny, usually,
that the hole exists). Is ageing a process, a deep, underlying
genetically driven ‘clock’ that starts ticking the day we are
born? This is the ‘programmed’ theory of ageing. Or is ageing
simply the name we give to the gradual build up of cellular
and DNA damage, largely from the environment and by
oxygen in the body, leading to a cascade of diseases? This,
broadly, is the ‘stochastic’ theory.
Oxygen plays a starring role in the story of senescence. If
death is the price we pay for sex, it might also be the price we
pay for not being yeast. Some time around 3,000 million years
ago, life invented photosynthesis. In the space of fewer than a
couple of hundred million years, the air started to fill with a
terrible poison. The nice cosy blanket of nitrogen, water
vapour and carbon dioxide was suddenly polluted with a noxious
gas with a terrible knack for ripping apart complex
organic molecules and playing havoc with the genetic code.
Nowadays we tend to think of this gas, oxygen, as a rather
good thing. You can do without food for six weeks, or water
for six days. You can’t last six minutes without a fresh supply of
this reactive molecule to go ripping through your body. But
oxygen is still a poison, which is not something that many
people realize. If you breathe pure O2 for any length of time
can i live forever please? 67
your throat will become raw and your airways inflamed by the
gaseous equivalent of a sugar-rush.
By adapting to oxygen and, eventually, co-opting it into
clever respiratory cycles, life hauled itself out of its anaerobic
stupor and started whirling and thrashing about with untamed
vigour. Oxygen is powerful stuff, allowing large
amounts of energy to be released quickly and efficiently when
molecules are broken down. But oxygen is a two-edged
sword. Its very reactivity damages the cells, and especially
their nuclear material, that allow our bodies to operate so
quickly. Just as plodding diesels tend to outlive highly tuned
racing car engines, our supercharged, oxygenated metabolisms
contain the recipe for their own demise. We start to rust,
from the inside out.
But oxygen isn’t the whole story. Another suspect in the
crime of death is the telomere. Telomeres are segments of
DNA that lie on the end of our chromosomes and they play a
vital role in preserving genetic integrity during cell division.
Every time a cell divides, a bit of its telomeres is lost. One
theory is that the inevitable shortening of telomeres is, in
effect, the ticking clock of ageing. Once they become too
short, the cell loses its integrity. In 1965, the biologist Leonard
Hayflick discovered that differentiated cells dividing in culture
can only divide about 50 times before dying. This is known as
the Hayflick Limit, and the shortening of the telomeres is
thought to be the cause. It is also thought that if a way could
be found to prevent the shortening of the telomeres then this
limit could be circumvented, and considerable research is
going on in this area.
But telomeres may be a red herring. It certainly seems to be
the case that removing the Hayflick Limit may not be a good
thing. The two kinds of cells that can replicate indefinitely are
all-purpose stem cells and cancer cells. By interfering with the
telomere-shortening process we may simply end up triggering
68 10 questions science can’t answer yet
the growth of runaway cancer. And it is not even clear that the
shortening of telomeres causes ageing, or whether the relationship
is the other way round. In some species of seabird,
telomeres actually lengthen with age. It is extremely difficult for
science to separate out the causes and effects of ageing.
Professor Steven Austad of the University of Texas is one of
the world’s leading gerontologists and also one of the people
best able to explain, simply, what is going on as we get older.
The evolutionary theory explains why we age; how we age is
basically down to the fact that we rust and that we cook. Our
cells, or the bits and pieces of organelle and metabolism contained
within them, are destroyed by oxygen as we burn fuel.
Austad likes the clock analogy, he says. ‘What we don’t understand
is what sets the speed of the clock. Damage happens for
a reason and happens faster in a mouse than in a dog and
faster in a dog than in a human. The key question is: what is
responsible for these differences?’
‘Ageing is a process which makes us increasingly vulnerable
to various diseases. It is surely something other than the sum
of our diseases though. Even the healthiest 50-year-old cannot
sprint as fast as he could at 20. That’s ageing in its purest
form.’ As we age, our bodies’ ability to cope with various kinds
of damage declines. Specifically, the ravages of reactive
oxygen and ongoing damage to our DNA seem to be key to
this process. But unravelling the nature of cause and effect is
proving difficult. If we see changes in our cells as we age, are
these changes the cause of the degeneration, or are they the
effects of some deeper underlying mechanism?
One interesting consequence, Austad points out, of the
ageing-as-process idea is the fact that we all become much
more different as we get older. Twenty-year-olds are much
more like one another than 80-year-olds, to put it crudely (to
put it most crudely, nearly all 20-year-olds will be alive, while a
goodly proportion of those potential 80-year-olds will not).
can i live forever please? 69
And it is true. We all know of people in their 80s and even 90s
who are quite capable of leading the same sort of active lives
that most take for granted in middle age or even youth. I
know one mid-septuagenarian who still goes hiking in the
Alps regularly, while I know plenty of people in their 50s or
even 40s unable to run a mile. Much of this is down to lifestyle,
to things like smoking and exercise and a lifetime of healthy
eating and so on, but much of it, even the bossiest of health
experts agree, is down to luck.
However lucky or virtuous you are, you will still grow old and
die. The question is, can anything be done about this? In a
way, it is surprising that more biologists are not working on
this problem. After all, their lives depend on it.
Gerontologists, people who study the biology of ageing,
disagree with each other, like all scientists. But there is one
thing they tend to agree upon, and that is that ageing is not
something we should try to stop. Leonard Hayflick has
roundly condemned the life-extortionists, people who want
to use science to extend human lifespan. It is rare to meet a
gerontologist who thinks that we should be trying to do this,
even if it is possible. Ring up just about any biologist in their
field and they will say the same thing. ‘We don’t understand
everything about ageing. But what we do understand indicates
that slowing the process down will be hugely difficult
and expensive.’ And, this is the key bit: even if we could, we
shouldn’t.
Why not? Here science drifts into morality. It seems to have
become a mainstream liberal view that altering human lifespan
is somehow wrong. One argument is that by making
people live longer science will contribute to the overpopulation
problem. Another is that research into anti-ageing therapies
will, as soon as it shows any sign of success, inevitably
siphon off just about every research dollar and euro going, to
the detriment of the rest of medicine. Finally, it is probable
70 10 questions science can’t answer yet
that any ‘cure’ for old age will have to be rationed by cost.
There will be yet another divide between the world’s haves
and have-nots.
These are rational arguments, but I believe there is another
unstated reason why so many scientists are opposed to antiageing
research. This is something akin to scientific Puritanism,
the feeling that whatever the logical objections and justifications
might be, this sort of thing just isn’t right. This is
strange, as there have been few objections, if any, to the great
strides that have been made in the past 200 years when it
comes to life expectancy. No one objected to vaccination or
antibiotics on overpopulation grounds, and although there is
an extremely vexed political issue concerning the cost of
antiretroviral drugs and their subsequent availability to the
poor, no one is suggesting that the research into a cure for
Aids should stop. This puritanical feeling is less strong than it
was, but it is still there.
So far of course, the argument is academic. Despite the
money spent, the research undertaken, the promises and the
marketing campaigns, the fact remains that not a single
potion, pill or treatment has succeeded in extending human
lifespan by one day. That is not to say that some people are
not trying. There are the beginnings of strategies out there
which may, one day, yield tangible results. The era of the
1000-year-old human may be a long, long way off, but the era
of the 150-year-old might not be.
Perhaps the simplest way of extending human lifespan
might be to make it illegal to have children before the age of
40. Michael Rose, professor of evolutionary biology at the
University of California, is one of the few biologists I have
spoken to who is enthusiastic about increasing human lifespan.
He famously bred ‘Methuselah’ fruit flies that lived
some 10% longer than average by using a form of simple
artificial selection – only allowing the oldest animals to
can i live forever please? 71
breed. ‘Oh yes, if you were a dictator you could increase
human life expectancy quite dramatically, simply by making
it against the law to have children before you were 40 or 45’,
he told me. The reason this works is quite simple – you are
removing from the gene pool anyone unfit enough to still be
healthy and fertile into middle age.
This won’t happen. What may happen is some sort of gene
manipulation. A number of ‘ageing genes’ have been identified
in organisms such as the fruit fly (Drosophila melanogaster)
and the nematode worm Caenorhabditis elegans. Extra copies
of a gene called Sir2 have been found to extend the lifespan of
both organisms. One of the most interesting discoveries in
recent years is how many key genes are shared right across the
range of species, from yeast to humans. One gene, called
RAS1, is linked to yeast lifespan. We have a version of this
gene, although it is not yet known if messing around with our
version of this gene will have the same effect.
A strategy that seems to have great promise derives from
one of the most depressing findings in the whole canon of
medical science, namely that severe calorie restriction seems
to prolong lifespan. There is plenty of evidence, from rats
mostly, that keeping animals in a state of near starvation
(while maintaining a balanced diet rich in vitamins and minerals
and so on) has a definitely beneficial effect on lifespan.
In studies going back more than 70 years, putting rodents
on brutally spartan diets has been demonstrated to extend
their lifespans by as much as 50% – the equivalent of getting
humans to live into their 150s or so. The calorie restriction
(CR) effect seems to be no respecter of species or even phyla:
worms, spiders and insects have all been shown to benefit.
The first proper human experiment in CR took place in 1991
when eight scientists sealed themselves inside a series of
linked geodesic glass domes in the Arizona desert. The project
was called ‘Biosphere 2’, an attempt to create a self-sustaining
72 10 questions science can’t answer yet
habitat completely hermetically sealed from the outside
world, ‘Biosphere 1’. One of those scientists was our Roy
Walford. He concocted an iron diet of a thousand or so calories
a day, containing all essential nutrients.
When the scientists emerged from their dome a couple of
years later the only one not in good shape was Walford, who
had hurt his back terribly in a fall from a girder. In subsequent
years, Walford promoted his life extension theories based on
low-calorie diets. The problem is that humans live a very long
time, and getting experimental data on lifespan extension in
humans is extremely difficult (it is much easier with fruit flies
and rats). The idea that to guarantee a ripe and healthy old
age we need to spend our lives in a state of near starvation in
one of the most depressing in the history of medicine. Could
there be other ways?
It is unclear at present how and why CR ‘works’. A popular
interpretation is that with less food there is less metabolic
activity and therefore fewer free radicals released into the
bloodstream by the cells’ mitochondria, which are forced to
work at maximum efficiency. Free radicals and other oxidizing
chemicals are thought to perform a key role in the ageing process.
By-products of our hunger for oxygen, they literally rust
our bodies away from within. A rival theory, the ‘Hormesis
Hypothesis’ states that being in a state of near starvation
stresses the body, generating a response not unlike the
immune response triggered by infection. This ‘hardens’ the
organism, placing it in a defensive mode and making it overall
better able to fight the diseases of ageing. Interestingly, the
same Sir2 gene linked to ageing rates in flies and worms seems
also to be affected by caloric restriction. This opens up the
possibility that it may be possible to mimic the effect of a starvation
diet using drugs or gene therapy.
Anti-ageing research is slowly becoming more respectable.
Most scientists still seem to be against it, but there is a shift in
can i live forever please? 73
attitude, particularly in America. Partly this is a function of
increasing wealth. Countries like the US are now far richer, in
absolute and relative terms, than any societies in history. A
poor man in today’s America or Western Europe has access to
riches beyond the wildest dreams of the Roman Emperors.
The rich today, and there are a lot of them, can literally buy
almost anything they want. Planes, cars, large chunks of
whole countries. But they cannot, as yet, buy more life.
Some scientists, Greg Stock among them, think that to
break the magical 125-year barrier we will need to change the
human germline, to alter our DNA. It may be possible to use a
combination of gene therapies and other drugs to mimic the
effects of calorie restriction without being hungry and tired all
the time.
Aubrey de Grey, an elaborately bearded scientist at Cambridge
University attracts almost universal derision among the
‘ageing community’ for his thesis that a ‘solution’ to old age is
just around the corner, probably consisting of a cocktail of
drugs and genetic therapies that will counter the effects of free
radicals and other harmful metabolic processes that weaken
the bones, make our skin brittle and cause our organs to
slowly fail. The attacks on de Grey are motivated by rational
scepticism, but also, I think, by that puritan morality that
states that life extension is a place where science has no place
going.
It is very probable that all the great advances in extending
human lifespan have already happened. Even when infant
mortality is taken out of the equation we are still in far better
shape than our great grandparents. A healthy 60-year-old
today can expect to live maybe another 25–30 years, and that
is the first time that has been the case in human history. Life
expectancy is continuing to rise in almost all societies, although
it remains to be seen whether the current obesity epidemic,
prevalent in many Western countries since the late
74 10 questions science can’t answer yet
1970s, will affect this trend in years to come (so far, strangely,
it seems not to be doing so). Immortality is a long, long way
off.
We can make rats live a long time by starving them, and we
can increase the lifespan of worms by tweaking their genes
and of flies by simply delaying the breeding age. But humans
are not mice, flies or worms. The man or woman who cracks
the ageing problem will become one of the most famous
people in history. I certainly wouldn’t bet on it never happening.
But sadly I will almost certainly not be alive to see it.
can i live forever please? 75
4
what are we going to do with the
stupid?
76
We don’t laugh at people’s DNA any more. Or refuse to give
people with certain genes, but not others, jobs. Nor do we
enslave them or prevent them from voting. And if we do, it is
generally accepted that we are doing a Very Bad Thing
indeed. And rightly so. This is new, of course. Just two generations
ago it was perfectly acceptable to mock and discriminate
against those of different skin colour and ethnicity, the very
small and the very tall, the brawny and the weak. in my country,
people, even quite nice people, talked openly about
‘Jewboys’ and ‘darkies’, ‘shortarses’ and worse. Those condemned
(perhaps) by their DNA to be homosexual were not
only discriminated against by the hoi polloi, but by the law.
It seems quite extraordinary now that in my lifetime it was
actually illegal for grown men in Britain to go to bed with each
other and have sex, and that hundreds ended up blackmailed,
ruined or in gaol for doing so – right into the not-so-swinging
Sixties. You could be discriminated against too for plenty
of non-genetic stuff. The one-legged, the crippled, the deformed
and the burnt were all subjected to often horrible
mockery. The past was a pretty ghastly place.
Happily that is all gone now, in polite countries at least.
(Crude genetic discrimination is still alive and kicking in much
of the world. There are countries, for example, where the possession
of testicles is deemed necessary to pilot an automobile.)
It has been swept away by rafts of equal opportunities
legislation, a new, liberal right-thinking consensus that operates
more or less across all mainstream political boundaries.
The current leader of the British Conservative Party, traditionally
the home of socially robust attitudes, has no detectable
homophobic or racist bones in his body. The ‘differently
abled’ are helped and ramped and made space for. Laughing
at someone because they are black or Jewish now seems
almost quaint, like poking fun at the peasants or employing
court eunuchs.
what are we going to do with the stupid? 77
But there is one area of genetic prejudice that remains perfectly
acceptable at all levels of polite society and, indeed, has
arguably become more acceptable in recent years than ever
before, and that is the prejudice against people born with a
low IQ. ‘What to do with the stupid’, to put the problem at its
crudest, is perhaps the greatest socio-political problem of our
time. It is a problem fuelled by scientific ignorance, wilful misunderstandings
and extreme prejudice. It is something that
scientists and social scientists are squeamish of even discussing
– just like life extension in this respect. Both left and right
have come up with solutions – solutions which, as we shall
see, are equally unsatisfactory.
Why on earth is a question like this in a book about scientific
mysteries? Surely this is politics, political correctness, the stuff
of education debates and sociology?Well, yes. But the issue of
variation in human intelligence goes right to the nub of one of
the most venerable and vexed scientific questions of all: the
relative importance of genes and environment in how an
organism develops during its lifetime. It is no mystery that
some people are brighter than others (although some people
still seem to dispute this). But it still seems to be deeply mysterious
as to the best way of going about dealing with this. Our
social scientists and economists have chosen, and for the most
part still choose, to ignore this problem.
There are some barriers to overcome when talking about
human IQ. For some, even to consider this issue is profoundly
unacceptable. ‘What do you mean, what should we do with the
stupid?’ a friend asked me after I wrote an essay on this subject
for the Spectator, a British political magazine. ‘The very asking of
that question is going to offend a lot of people.’ And of course he
was right. Even suggesting there is a problem is going to cause
trouble. For a start, debates about the relative intelligence of different
people always risk straying into some very dark waters
indeed (although of course they shouldn’t).
78 10 questions science can’t answer yet
Even talking about IQ gets you into trouble in some quarters.
Lots of people decry IQ tests as meaningless – ‘they are a
measure of your ability to pass IQ tests’ is a common sneer –
but the fact is that while a good test may not be measuring
pure intelligence per se, it does seem to be measuring something
that correlates very well with it. People who score highly
in IQ tests tend (not always of course) to be generally regarded
as ‘bright’. People who score very highly indeed may well
be a bit strange, eccentric, weird and lacking in social skills,
but many more are not. Life’s achievers are predominantly
drawn from the ranks of the high-IQed, not low. Let’s assume
for the sake of this argument that the term IQ does mean
something.
So who are we talking about when we use the word ‘stupid’?
We are not talking about the profoundly mentally handicapped,
nor those who have lost significant cognitive function
through ageing, injury or disease. In most wealthy and
humane societies people with – to put it very crudely – an IQ
much below 70 are cared for by the state, or with some state
help and guidance, either in or out of the community. These
people are often not considered ‘ill’, yet it is also accepted that
they will find it hard to take an active role in society without at
least some outside help. No, the people I am talking about fall
into an unhappy no-man’s land on the IQ scale – too bright to
be regarded as truly disabled, but for the most part lacking the
intellectual skills to survive easily in what is becoming an
increasingly knowledge-based world. These people suffer discrimination
at every turn, discrimination wired into the whole
fabric of most societies on Earth. And it is discrimination that is
getting worse.
Something that is not appreciated at all is the fact that it is
quite hard for a person living in a technological society, the
‘modern world’ if you like, to earn a living wage if he or she is
illiterate – something that was certainly not the case say 150
what are we going to do with the stupid? 79
years ago. Then there were plenty of jobs that relied purely on
brawn rather than brain. In 1900 more than a million British
men worked in the mines, and millions more in the fields.
During the 19th century millions of immigrants poured into
the US, some of whom became doctors and lawyers, but the
vast majority went to work on farms and in the new factories.
Many of these blue-collar jobs were highly skilled and required
training and intelligence, but most were not. Now most of
those jobs have gone.
This is not of course to say that all those old miners and farm
workers were illiterate or of low intelligence. Many were
extremely bright. In fact, in the old days, when one’s place in
society and one’s job prospects were determined largely by
accidents of birth and geography, you could probably find
pretty much the same distribution of mental abilities among
the ‘lower’ classes as among the wealthy. This is something
that cannot be true today.
The proportion of the workforce who can carry out their
paid tasks with no educational qualifications is far smaller than
it ever has been. To earn a decent working wage in mostWestern
countries you need far more brain than brawn. Of course,
there are still jobs open to those with purely physical skills, but
they are far fewer in number than ever before. Most of the
labourers are no longer needed, and unskilled manual work is
increasingly being farmed out to poorer countries. Only a tiny
elite can earn a living playing sport. You may not have to be
that bright to be a successful footballer or model, but you do
need a highly unusual physical talent and/or physique.
In Western countries, jobs considered ‘blue collar’ or ‘working
class’ now often demand significant intellectual input. The
modern ‘factories’ are the call centres, giant warehouses full of
unfortunates making and answering endless telephone calls
concerning bank accounts, insurance and the whole panoply
of life that cannot be dealt with in a retail store or on the
80 10 questions science can’t answer yet
Internet. Many people mock these jobs and those who do
them, forgetting perhaps that they require significant skills – a
good command of the language and of the nature of the business
to hand, good conversational skills and the ability to
operate a complex computer system at some speed. Working
in a call centre is not the equivalent of baling hay or breaking
rocks.
So what are the options open to the people who simply
cannot join in modern life? Precious few, it seems. One function
that the less bright can perform is to act as society’s collective
court jester. Think of all those hideous and cruel TV
shows designed to showcase the dim for our delectation (for
that is the real point of Big Brother and Wife Swap and Holidays
from Hell and all those dreadful ‘reality’ programmes that
appear to have got the world hooked). Of course, we have
always mocked our fools – but it seems to me that the vitriol
directed at the not-very-bright is a nastier and more powerful
concoction today than it has ever been. And as the old class
barriers break down and the tectonic plates of society realign,
it is these people who sink inexorably to the bottom. And, not
being bright, they lack the wherewithal – and especially the
leadership – to get themselves out.
The dangers of a society where intelligence and effort are
rewarded more than accidents of birth were first noted by the
social scientist Michael Young. In his 1958 satire The Rise of the
Meritocracy, Young pointed out that in a society where your
status was defined by your merit – he defined this as ‘intelligence
+ effort’ – the elite will tend to feel wholly entitled to the
privileges they enjoy.
This rather unexpectedly contrasts with the old class-based
system, which, for all its raging, foam-flecked snobbery, tacitly
acknowledged that your station in life was pretty much a
matter of luck, and hence one should not brag too much
about one’s success or sneer at those less fortunate than onewhat
are we going to do with the stupid? 81
self. The new ‘meritocratic’ way of thinking can now be seen
in the United States (although in fact America is not nearly as
meritocratic as it likes to think). In the US, people talk freely
about ‘losers’ and ‘folk who take the bus’ in a way that seems
extremely alien and unkind to people from older, perhaps
more traditionally stratified, societies. Failures are failures
because it’s their fault. But, of course, when it comes to intelligence
it isn’t, any more than it is someone’s fault for being
black or Jewish, or very tall or blonde.
So who are these unfortunate people? In most developed
countries, roughly 68 per cent of the population have an IQ
between 85 and 115, and the numbers living above and
below these limits are roughly equal.
Within and above the ‘average’ range, most people will be
able to function fairly well in our society, but what about the
10–15 per cent or so that lie below IQ 85 and above 70? Today
many of them inevitably become the genetic underclass of IQchallenged
unemployables, forever drifting along the crimedriven,
drug-using margins of our society. Lots of them are in
prison (along with the mad, the sad and the bad). Being working
class was a rum deal; being underclass is far, far worse.
Intelligent people, like tall men and pretty women, have
always earned far more money, had higher status and happier
marriages, been healthier and less likely to be in jail than the
stupid. But the point is that this is becoming more the case as
society becomes more ‘advanced’, and driven by technology
and data. One interesting corollary of the value we now place
on brainpower is the relatively new phenomenon of the desirable
alpha female.
Being extremely bright, if you were a woman, was not much
of an advantage in most societies until quite recently. In Victorian
Britain, for example, the opportunities for a woman to
earn her living through brainpower alone were extremely limited.
According to the 1901 Census, there were fewer than
82 10 questions science can’t answer yet
two hundred registered female physicians in the whole of the
UK. Going to university was difficult and expensive – most did
not even allow girls to study. You could become a teacher, perhaps,
or a governess, or maybe, if you were exceptionally talented,
earn your living writing or in the arts. Most of the
professions were closed, as was the world of business.
Being bright and female did not even increase your chances
of finding (or being found by) a desirable mate. In fact, it lessened
it, as many bright women were loath to make the
financial sacrifice that would inevitably follow marriage. Traditionally,
in Europe and its offshoots at least, alpha males, in
having the pick of the females, would tend to choose on looks
and background rather than intelligence. The dumb blonde
hanging off the arm of the successful politician or businessman
is a horrible cliché, but it has an element of truth.
Things are changing. Alpha females use their brainpower to
their economic advantage, and are thus now far more desirable
mates. Powerful, successful men these days seem to be
choosing equally powerful, successful women as partners in a
way that did not happen in the past. This is having some interesting
effects according to some scientists.
It may have a polarizing effect on the IQ ‘bell curve’, the
statistical graph of intelligence quotients across the population.
With the brightest men and women being effectively
taken by each other, the overall effect may be a flattening of
the ‘bell’ – more very bright people, and perhaps more very
dim. It is too soon for this effect to be seen; it is, after all, only
very, very recently that the whole phenomenon of the alpha
female has existed at all. As late as the 1960s the marriage
bar still existed in most professions, and women in government
jobs were, quite openly and officially, paid less than
theirmale counterparts for doing the same job. There is still a
30% salary discrepancy, although the reasons are now less
clearly stated.
what are we going to do with the stupid? 83
Another interesting suggestion is that these changed mating
patterns may lie at least partly behind the puzzling epidemic of
autism. Higher – far higher – percentages of children are now
diagnosed with ‘autism spectrum’ disorders than were even
two generations ago. The figure for 1970 in the US, for example,
was 1 in 2500; today it is 1%, an astonishing increase mirrored
in many other countries. The cause is a mystery. It is too
recent to be some sort of general genetic shift. Environmental
factors have been mooted, particularly exposure to certain vaccine
combinations. Many people in Britain remain convinced,
after high-profile media campaigns, that the MMR triple vaccination
routinely given to young children can trigger autism,
even though the scientific consensus is that there is no such
link. Of course, much of the increase in autism can be attributed
to better diagnosis. But this cannot explain all of it.
One plausible explanation has been offered by Simon Baron
Cohen, a psychologist and director of the Autism Centre at
Cambridge University. He thinks that ‘assortative mating’ may
play a part. Specifically, it is becoming more likely that men
and women with ‘male brains’ – logical and systematic – will
mate with each other and have children. In a 2006 article in
Seed magazine he wrote:
Consider that in the late 1950s, less than 2 percent of
undergraduates at MIT (a university that caters to people
with good systemising skills) were women. Today female
enrolment has jumped to 50 percent. This microcosm is
just one example of how society has changed in ways that
would bring strong systemisers into greater proximity.
Over the same period, air travel has also meant far
greater opportunities for people from widely differing
backgrounds to meet, possibly brought together by their
common interest in systems. Finally, over this same timeframe,
individuals who are systemisers have enjoyed new
84 10 questions science can’t answer yet
employment opportunities as the result of the digital revolution.
Where 50 years ago a strong systemiser might have
found a job as an accountant, today every workplace
needs computer-savvy employees, and the financial rewards
for good systemising skills can be immense.
Baron Cohen’s thesis has attracted some controversy, both
among those who are convinced that autism must have a primarily
environmental cause and among others who claim that
talking about any aspect of mind and genes in the same
breath is tantamount to being a Nazi.
To the blank-slaters, those ideologically opposed to any
innate differences in mental ability at all, the traditional satisfactory
solution to the IQ problem is to deny that it exists. This
sort of thinking led to the bizarre and hugely counter-productive
social science model, which took hold among the educational
establishments in the West in the 1960s.
This is the traditional solution of the well-meaning left, to
pretend that the stupid simply aren’t there. This is dangerous,
and harmful, mostly to the stupid themselves. Educational
policy in manyWestern countries, most notably Britain
and some parts of the US, still reflects this thinking. By pretending
that all children are equal, and having a bitter insistence
on inclusivity (which can also see the quite severely
disabled educated in mainstream schools, to the detriment
both of them and of their more able classmates) the less
bright have been left floundering, failed by their teachers
who are forced to teach that mythical average child (the one
who often, mysteriously, fails to show up for classes) and by
an examination system that rewards only academic merit at
the end. Thus millions of teenagers leave school branded as
failures, unable to meet the gold standards academically and
yet with no alternative training in skills in which they might
be able to excel.
what are we going to do with the stupid? 85
Much more is made of the fact that this system also fails the
very bright. It can, but I would argue to a lesser degree. The
bright will usually look after themselves and tend anyway to
receive most of their basic education from their parents and
from books. One’s advantages in life tend, after all, to be won
before one is even born. No, it is those who are below average
who suffer most when it is pretended that everyone is the
same.
Believing that the stupid are not there is, on the face of it, an
extraordinary thing to believe. For to do so we must accept
that human (or any other) intelligence has little or no genetic
component. Now, unless our minds are the property of some
nebulous ghost in the machine, and not of flesh and blood,
this surely cannot and need not be so. I have never understood
why people who are quite happy to accept genetic differences
in, say, athletic ability, susceptibility to sunburn, and
even complex traits like sexuality, are still fundamentally unable
to see that our minds may have a strong genetic component
too.
Obviously and facetiously this must be so, otherwise humans
would be no brighter than halibuts.
In British author Matt Ridley’s excellent book, Nature via
Nurture, the way in which environment and genes work
together is explained. If you have Einstein-class DNA, you still
need supportive parents, and books and schooling and so on,
for your potential to develop. Your environment unlocks the
potential in your genes (just as a good diet unlocks your
genetic potential to be tall). But that doesn’t mean that your
genes don’t matter. The left’s solution – there are no stupid
people – is simply not viable.
So what about the right? What do they have to say? By the
‘right’ I include those Communist regimes whose educational
systems were largely based on the rigorously streamed Prussian
model that was copied in the old Soviet Union. I also include
86 10 questions science can’t answer yet
those counter-revolutionary educationalists who clothe themselves
in traditional rigour, and also self-avowedly meritocratic
societies and institutions which consciously reward ‘ability’
when that ability always has a large intellectual component.
The right’s solution to the stupid is to accept that they exist but
then to go on and ignore them and wish they would go away.
It is interesting to speculate about what will happen to
human intelligence, for there are strong and mutually contradictory
forces that appear to be at work here. A hundred years
ago brawn may have mattered far more than it does now, but
a hundred thousand years ago the opposite may have been
the case. We do not know what drove the evolution of our
bizarre, energy-hungry brains, but it is thought that the ability
to develop and acquire technology was probably a happy byproduct
of the process rather than the primary cause. A convincing
argument has been made for our intelligence developing
as a social implement. We have big brains because they
are good for gossip. Did the acquisition of language precede
the acquisition of intelligence? We don’t know.
Whatever its origins, the big human brain became a useful
survival tool. High intelligence would have granted perhaps
greater social status and therefore greater choice of mate.
Being clever would also have improved survival prospects,
especially as technology developed. Clever people would
have been better hunters and cannier gatherers, and probably
better at looking after children and making plans. Before the
development of specialized labour, which came along with
the neolithic farming revolution, a successful human probably
had to be something of an all-rounder. This is pure and idle
speculation, but it may well have been the case that pure
brawn and brawn alone was no more useful in the Old Stone
Age than it is now.
We know that human brains grew over time. The skulls of
people who lived 80,000 years ago were always bigger than
what are we going to do with the stupid? 87
those of the hominids who lived at earlier times. High intelligence
confers such obvious advantages that it is most probable
that the driver for this brain expansion was simple natural
selection. But that raises the question: what will happen now?
Some scientists talk about Homo sapiens as being the first postevolutionary
species. With a conscious awareness of our own
evolution, plus the technology and wherewithal to influence
and even negate the traditional forces of natural selection,
what will happen to our brains now?Will they shrink? Or carry
on growing?
One argument says that we will become dumber. In most
Western societies, the argument goes, those of low educational
attainment tend to have more children than those
with university degrees. Since intelligence has a high inheritable
component, this will tend to drive average IQ down.
But there are problems with this argument. Firstly, the tendency
of the lower socioeconomic groups to have more
children than other groups is rather new and geographically
limited, and may be very transient. Traditionally, in
Europe say, it was the wealthy who could afford to have
more children. Upper class women would traditionally
marry earlier and have more babies than their poorer sisters,
as they would have been depended upon to make an
economic contribution by working. It is true that in countries
with a strong welfare state, fecundity is quite strongly
correlated with low socioeconomic status, but this is not
universal by any means. In countries where ‘welfarism’ is
less prevalent, such as the US, the wealthy and educated
can and do outbreed the poor.
Secondly, there is the undeniable and rather mysterious fact
that we seem to be becoming brighter. In just about every
industrial society, average IQs have risen quite dramatically in
the last half a century or so. This cannot be evolutionary –
there have not been enough generations for natural selection,
88 10 questions science can’t answer yet
genetic drift or some other evolutionary mechanisms to have
taken effect. Something must be acting on the raw genetic
component of intelligence to bring out the ‘best’ in our brains.
What was ‘quite bright’ three generations ago is now merely
average. What could it be that has caused this?
There are several possible candidates. Better diet is one. This
could explain the dramatic rise in IQ levels seen in some Asian
countries since the SecondWorldWar. But this would not adequately
explain why IQs have also risen in countries like the
US, UK and France, where diets have not changed significantly
in 50 years. Indeed, the British probably ate better during and
just after the Second World War than at any time before or
since. Food rationing meant more, and better quality, food for
a majority of the population. Yet austerity Britain was probably
a bit dimmer than it is today.
Better education must have had an effect, but again there is
little evidence that this could have had much of an influence in
the short time-scales involved, in Western European countries
at least. A popular, but left-field, suggestion is that it is all
down to television. Far from being an idiot-box, the TV may
be literally pummelling your child’s brain into shape, producing
a welter of complex non-stop visual stimulation. According
to this theory, it may not even matter what sort of
television you watch; cartoons are probably as good as the
Discovery Channel. It’s a nice idea (computer games may play
a part too), but it is wholly unproven.
The low-IQ problem will probably never be tackled. Intelligence,
unlike skin colour, athleticism, height, weight or any
other gene-influenced attribute goes to the very heart of what
it is to be human. The less-than-bright are seen as less-thanhuman.
They are being left behind faster and faster, and the
phenomenon will become global if and when the developing
world starts to catch up with the industrial countries economically.
In the most fiercely technocratic societies, like those in
what are we going to do with the stupid? 89
some Asian countries, where success in life is determined
almost entirely by the ability to pass a series of extremely
tough academic hurdles, being dim must now be very, very
hard indeed. One answer of course is to massively improve the
quality of education available. A good proportion of any society’s
intellectual also-rans can be brought into the IQ mainstream
with better schooling. But with the best will, and the
best schools, in the world, there will always be some left
behind.
The not-very-bright are mocked, are less healthy, have a
smaller pool of mates from which to choose, are more likely to
be unemployed and poor, and are far more likely to drift into a
life of crime. They exist in a society which not only derides
them but which places a series of hurdles in their way deliberately
designed so that they will fail. This is manifestly unfair.
When is somebody going to do something about it?
90 10 questions science can’t answer yet
5
what is the dark side?
91
In late 2005 I was privileged to gaze upon one of the marvels
of the modern world. Buried around 30 metres under the
Swiss–French border, near Geneva, is a roughly circular
tunnel, about 27 kilometres long. The tunnel is lined in grey
concrete, with a painted floor, and is about three metres
across. It makes a nice, if somewhat dispiriting, running track,
the wall curving endlessly and rather hellishly away in both
directions as you puff your way around. In fact, informal races
have been held in it; a good time for a circuit is two hours. A
more common means of transportation would be a bicycle or
one of those two-wheeled electric buggies. I was lucky to get
into this tunnel, because from now on and for a good while no
one else will be going down there.
The tunnel forms part of one of the most impressive engineering
feats in history, part of a scientific instrument gargantuan
in both scale and intent. Like the greatest of the
telescopes, atop their Canarian and Chilean peaks, the big colliding
tunnel at the Conseil Européen pour la Recherche
Nucléaire (CERN), is a multi-billion-dollar behemoth designed
to expose the deepest realities in our Universe.
At several points around the CERN ring are some of the
most awe-inspiring bits of engineering I have ever seen:
vast, unfathomable polygonal rings, made of Russian pigiron
and British steel, French titanium and German plastic,
and several million metres of wiring and ducting. These
assemblages are as big and heavy as ships, and have been
lowered into artificial caverns as voluminous as cathedrals.
This is Big Science. In November 2007, after some ceremony
with the on-button, these Brobdingnagian structures
will witness the first deliberate collision of packets of particles.
The heavyweights of the sub-atomic zoo, protons and
neutrons, will slam into each other at near light velocities
after being accelerated around the ring by giant superconducting
magnets.
92 10 questions science can’t answer yet
The Large Hadron Collider (LHC) is the largest and most
expensive physics experiment in history. It has a series of
goals, none of them modest. One is to find the elusive Higgs
Particle, the object (or should we call it a field?) that is thought
to permeate the Universe and to give everything its mass.
And another is to discover the nature of dark matter. It is a
good thing that this huge machine has been built, because
dark matter is one of the biggest embarrassments in science
and its nature one of the biggest unsolved mysteries.
Unlike some of the other problems in this book, dark
matter is something of a blank slate; we really do not have
an inkling of what it is or where it came from. It is asmysterious
as human consciousness. About 4% of the total ‘stuff’
(mass + energy) in the Universe is thought to be composed
of well-behaved ordinary matter, the stuff of stars and planets,
you and me. Dark matter, whatever it turns out to be,
accounts for another 22% (so there is five and a half times as
much invisible matter in the Universe as there is visible
matter). The rest is made up of dark matter’s even madder
and more mysterious cousin, dark energy, of which more
later.
We have some ideas as to the nature of dark matter, but
nothing concrete. And thanks to the construction of vast
atom-smashers like the LHC we may find ourselves going from
a position of total ignorance to total understanding about one
of the biggest mysteries in the Universe in a matter of just a
few years or even months. Now that would be an extraordinary
result.
Dark matter is by far the most common ‘stuff’ in the Universe,
and yet no one has really the faintest clue what it is. It is
hoped that the very high energies generated by the collisions
in the LHC will blast the particles that form dark matter out of
hiding. Whether we will ever be able to get to grips with dark
energy remains to be seen.
what is the dark side? 93
Dark matter has been bothering cosmologists for some
time. Since the 1930s, astronomers have been uncomfortably
aware that the amount of matter visible in the cosmos is not
nearly enough to account for the movement of the stars and
galaxies that we observe.
In 1933, the Swiss astronomer Fritz Zwicky, working at the
California Institute of Technology (Caltech), analyzed the
movement of a cluster of galaxies and discovered that it could
only be accounted for if a large amount of unseen mass – far
greater than the visible stuff, which is mostly stars – was lurking
in the area. This anomaly has now been seen everywhere
we look. The large, visible objects in the Universe (the galaxies
and the stars in them) behave as if huge amounts of invisible
matter are pulling them about.
So the search for the Universe’s missing matter has become
one of the biggest stories in science. Theories have abounded.
Maybe the dark matter is just ordinary stuff that is hard to see
– rocks, asteroids, lone planets and brown dwarf stars too dim
for their light to be detected. Or maybe it is made of vast
clouds of gas and dust.
Some of the missing matter is undoubtedly just this, but
most of it cannot be. This much ordinary matter would leave
an unmistakable mark in the form of re-radiation of electromagnetic
energy, which we simply do not observe. No, most
physicists now believe that dark matter is composed of some
novel subatomic particle. A current front-runner is a hypothetical
particle called the axion. Proposed in 1977 to clean up a
few equations involving the strong nuclear force (one of the
fundamental forces of nature), axions make good candidates
for the dark matter particle because they have very little mass
(although they certainly have some) and will barely interact
with matter.
In July 2006, tantalizing evidence for the existence of
something very like axions came from the National Laborato-
94 10 questions science can’t answer yet
ries of Legarno, in Italy, where a particle accelerator generated
a slight shift in the polarization of a laser beam fired
through a magnetic field. The finding is controversial, but in
early 2007, New Scientist reported that an attempt was being
made to persuade the people in charge of a soon-to-bedefunct
accelerator called HERA to be pressed into service to
try to duplicate the results, something which this accelerator
is currently in a unique position to be able to do. But for the
moment, dark matter remains, in physics terms, terra incognita.
There is good news though. We may not really know what
dark matter is yet, but at least we have spotted where it lurks.
In early 2007, Richard Massey, of Caltech, and colleagues,
published in Nature1 the first ‘picture’ of the distribution of
dark matter in a large chunk of the nearby universe. Because
we cannot see dark matter directly, we infer its existence from
its effect on things we can see.
Massey’s team made their map from nearly 1000 hours of
observation by the Hubble Space Telescope of around half a
million galaxies using a technique called weak gravity lensing.
Dark matter, though invisible and transparent, has gravity,
and thus, like any object, affects light or other radiation that
passes through it or nearby. Simply put, if there is dark matter
between you and a galaxy you are looking at, the direction of
the light from that galaxy will be bent very slightly because
the dark matter acts as a giant lens. Massey’s team mapped
the distortion seen in the Hubble images to work out where
these invisible lenses lie.
Writing rather poetically in Nature, physicist Eric Linder, of
the Lawrence Berkeley National Laboratory, compares this to
an old technique used here on Earth:
In the manner akin to Polynesian seafarers who sense
islands out of their sight through the deflected direction of
what is the dark side? 95
ocean waves, cosmologists can map a concentration of
the Universe’s unseen mass through the gravitational
deflection of light coming from sources behind it.
Apparently, dark matter is not arranged randomly. It is
clumped into vast blobs on a grander scale than even the galaxies
themselves. Combining the Hubble data with groundbased
observations produced a crude 3D map of dark matter.
It appears to form the scaffold upon which the visible matter
of the Universe, the galaxies, is assembled. Visible galaxy clusters
seem to be embedded in vast clumps of dark matter connected
by titanic bridges of dark matter called filaments.
Cosmologists now suspect that early on in the formation of
the Universe the dark matter formed a framework around
which ‘normal’ matter could coagulate. Today, dark matter
also seems to be clumped into ghost galaxies. Recent observations
of ‘dwarf spheroidals’, small dim galaxies which have
been detected orbiting both the Milky Way and the great
Andromeda spiral, show them to consist almost entirely of
dark matter, their ordinary matter stripped away billions of
years ago by the gravity of their giant neighbours.
Edwin Hubble’s realization in the 1920s that the Universe is
hugely vaster than the single galaxy that it was once thought to
be, that it was expanding at a furious rate and that the edges of
space and time are likely to be forever beyond our gaze, was
perhaps the ultimate triumph of Copernicanism, the relegation
of humans and their affairs to the periphery of creation. But the
discovery of dark matter and, as we shall see, dark energy,
pushes the ‘world of us’ even further towards the edge of what
appears to be important. Not only does the little Earth go
round the Sun, not only is our galaxy just one of billions, but it
turns out that even those countless galaxies are made of some
sort of peripheral stuff that is a mere adjunct to the bulk of the
Universe.
96 10 questions science can’t answer yet
If dark matter is terra incognita, then dark energy amounts to
the dragons that live there. It accounts for the remaining three
quarters of the missing mass-energy account of the Universe.
It sounds like something out of science fiction, vintage Asimov
perhaps, yet it seems to be quite real.
Dark energy is a strange force field which permeates all of
space, creating a repulsive force that seems to be causing the
Universe to expand. It was first mooted by Einstein. He considered
it an unfortunate bodge and his ‘greatest mistake’.
Today, physicists agree that something very like Einstein’s
bodge, a repulsive force which stops the galaxies falling into
each other due to their mutual gravitational attraction, is
needed to explain the Universe that we can see.
It may have been Einstein who first hinted at the existence of
a mysterious, all-pervasive energy field, but it wasn’t until 1998
that astronomers realized that the expansion of the Universe –
actually the expansion of the Universe’s fabric, space–time, in
which the superclusters of galaxies are embedded – was slower
in the past than it is today and is hence accelerating.
The discovery was made by observing distant supernovae,
which can be used as markers of the speed of expansion of farflung
bits of the Universe, just as hydrologists throw brightly coloured
balls into rivers to measure the velocity of thewater in various
streams of the channel. One explanation is that gravity
works in different ways at different scales. But it is now accepted
that some form of energy is pushing the galaxies apart.
In a Scientific American2 article in February 2007, the astronomer
Christopher Conselice described the essence of dark
energy nicely:
The very pervasiveness of dark energy is what made it so
hard to recognize. Dark energy, unlike matter, does not
clump in some places more than others; by its very nature
it is spread smoothly everywhere.
what is the dark side? 97
Certainly, on small scales there isn’t very much of it. Every
cubic metre of the Universe contains dark energy equivalent
(via Einstein’s famous equation E = mc2) to some 10–26 kilograms,
about the same as a handful of hydrogen atoms. All
the dark energy in our Solar System amounts to the mass of a
small asteroid. But, unlike small asteroids, dark energy is absolutely
everywhere. A few atoms’ worth in your living room, an
atom or so’s worth in your head.
And if there is one thing the Universe is not short of, it is bulk
volume. Over vast, cosmological distances and vast tracts of
cosmological time, the effects of dark energy are, to say the
least, substantial. Dark energy acts as a gigantic cosmic sculptor,
not only determining the overall expansion rate of the
Universe, but also the structure of the smaller-scale ‘scaffolding’
on which the galaxies are hung.
Dark energy has a negligible effect on anything smaller
than the supercluster scale. It is not, for instance, causing our
own galaxy to expand (at least not yet). On the scale of thousands
of light years and everything smaller, gravity dominates.
It is only when you move to the million- and hundredmillion-
light-year scale that dark energy starts to make its
presence felt.
Dark energy could be significant in other ways. The ‘current’
Universe is quite different to the early one. Today’s galaxies, by
which we mean the ones relatively close by, are large, stable
affairs compared to the often violent, colliding star agglomerations
seen when the Universe was, say, half its present age.
Star formation seems to have slowed down.
And some of the Universe’s most dramatic objects seem to
have become extinct; it cannot be just coincidence that the
quasars and violent radio galaxies seen at billion-plus light
year distances are absent in the nearby Universe. Quasars are
thought to be powered by supermassive black holes, superficially,
at least, similar to the type found at the heart of the
98 10 questions science can’t answer yet
Milky Way. Yet the heart of our galaxy is (fortunately for us)
not a quasar and our black hole is very well-behaved. Some
astronomers see the hand of dark energy in this apparent cosmological
evolution.
Unfortunately, dark energy does not behave like any other
energy field. It is not like gravity (which is generated by mass);
nor is it like the nuclear or electromagnetic forces. It seems to
come out of nothing, from the vacuum itself. Vacuum energy
is a favourite candidate for dark energy, but the trouble is that
when physicists work out how much energy should be generated
by the random quantum fluctuations of empty space
they come up with a value about 10120 times larger than dark
energy actually appears to have.
This holds the current and rather embarrassing record for a
disparity between observed and theoretical values of just
about anything in all of science. Dark energy is strongly suspected
to be the energy that put the ‘Bang’ into the big one,
and the energy which powered the stupendous expansion of
the Universe in the fleeting instants after. But, like dark matter,
we really don’t know what it is, how it was generated or why, if
it was the energy source for the Big Bang and the subsequent
cosmic inflation, it has dissipated in power so much since. And
while dark energy appears to be a shadow of its former self,
some models predict that it will once again become a dominant
force in the Universe to rival and even supersede gravity
as the major sculpting agent of matter on the scale of planets,
or even smaller, rather than on cosmological scales.
One day, dark energy may become so strong that it may rip
apart star systems, throwing planets out of their orbits and
even shredding the planets and stars themselves. One eschatological
scenario has dark energy operating at a level where
even individual atoms and bits of atoms are finally ripped
apart: the Universe exploding, its death throes dubbed the Big
Rip.
what is the dark side? 99
In the medium term we (or rather ‘we’, meaning intelligent
life in general, if there is more than just us out there) may have
cause to be thankful to dark energy, as it looks certain that if
nothing else it will ‘save’ the Universe from one of its more
grisly postulated fates, the so-called Big Crunch. This would
be our future if mutual gravitational attraction were to one
day overcome the cosmological expansion. But in the end, the
dark energy would get us just as surely as if our fate were to be
a fiery rerun of the Big Bang in reverse.
Some scientists hope that dark matter and dark energy will
simply go away. There are persistent attempts to show that
both could be the results of errors in interpretation or substance
in quantum physics or relativity. Possibly there is no
dark energy and we will have to rethink our ideas about how
gravity works over huge distances and time-scales. But both
dark matter and energy are proving to be stubborn monsters,
and neither will vanish helpfully from the equations; the
majority view is indeed that the Universe is swarming with trillions
of suns’ worth of indefinable matter and that the whole
shebang is being blown up and expanded by a strange antigravity
force field that may one day rip it apart.
Dark matter and dark energy are perhaps the Universe’s ultimate
way of making us feel small. When contemplating the
grandest mysteries, humankind has built grand machines. The
great henges in southern Britain and France, astronomical calculators,
were the Large Hadron Colliders of their day.
It is fitting that the Hubble telescope, very much now in its
twilight years, is now being used to map the vast swathes of
dark matter which dominate our Universe. Hubble has found
it; the LHC at CERN may yet tell us what it is. It is a nice
thought that in a few thousand years’ time archaeologists may
stumble upon the rusting, crumbling remains of the CERN
colliders and wonder just what they were used for, just as we
do with Stonehenge and its fellows today.
100 10 questions science can’t answer yet
References
1 Massey, R. (2007) Dark matter mapped. Nature, Online edition, 7
January.
2 Conselice, C. (2007) The Universe’s invisible hand. Scientific
American, February. http://www.sciam.com/article.cfm?chanID=sa
006&colID=1&articleID=1356B82B-E7F2-99DF-30CA562C33C4F03C.
what is the dark side? 101
6
is the universe alive?
102
If dark matter is odd, life is positively bizarre. Being alive ourselves
we take it rather for granted, yet on even the most basic
and fundamental levels what it means to be in the world of the
quick rather than of the inanimate is oddly unclear and undefined.
Life is perhaps the most mysterious property of our Universe.
Its existence means that the cosmos is now aware of its
own existence in at least one place, and maybe countless
others.
We do not know how, where or when life began. We do not
know if it started once on Earth or on many occasions. We do
not even know for sure if life, our life, began on this planet or
elsewhere. We do not know if life on Earth is unique, rare or
startlingly commonplace. Do we live in an isolated oasis, a
cosmos full of amoebae or a Star Trek-type universe, teeming
with intelligent species? Finally, we do not really even have a
proper working definition of what life is.
Until quite recently these questions were, rather strangely,
not high on science’s agenda. Despite the explosion of biological
research in the 20th century, the most fundamental questions
about life remained strangely on the fringe. As to the
origin of life, for example, the consensus view that Charles’s
Darwin’s throwaway line about the first primitive beings arising
spontaneously in a ‘warm little pond’ would more or less
do. This ‘primordial soup’ hypothesis sounded so plausible, so
eminently believable, that it was probably thought best to
leave it alone.
Speculating about life in space was, until quite recently as
well, rather infra dig. The whole notion of the alien had been
popularized by science fiction, the delusions of the UFO brigade
and by people like Percival Lowell and Arthur C. Clarke,
who straddled the borderlands between science and fantasy.
The fact that when serious space exploration began in the
1960s and it was found that the first worlds we went looking
at, the Moon and then Mars, seemed almost certainly lifeless,
is the universe alive? 103
led to the view that alien life was not really something that
proper scientists concerned themselves with.
But it is all rather different now, and the nature and origin of
life is one of the hottest questions in science. Astronomers
have made several startling discoveries in just the last few
years that seem to make the possibility of life elsewhere far
more likely than even a couple of decades ago.
‘Biogenic’ chemicals closely associated with life, from simple
elements like carbon to complex organic molecules like amino
acids, have been found everywhere we look. We can detect
molecules like ethanol spectroscopically in distant dust and
gas clouds, and when we crack open meteorites we find far
more complex compounds that may be the precursors to life
itself. If all that life needs to get going is the right chemistry
and a nice warm planet to live on, the inescapable conclusion
is that it is everywhere.
?
The origin of life on Earth is still a rather embarrassing mystery.
If it were a religious issue the best analogy would be that of the
Second Coming. A central tenet of the Christian faith, the
return of Jesus Christ, is now more or less ignored by the mainstream
churches, despite the fact that in the early days of the
church it was a hotly debated issue.
Something quite similar seemed to be the case with biogenesis
until fairly recently. Most textbooks seemed to gloss
over the problem, much as Darwin himself did, speculating
that the horrendously complicated biochemistry necessary for
life somehow bootstrapped itself into existence in that warm
little pond. Take a handful of carbonaceous gloop (without
104 10 questions science can’t answer yet
asking too hard how it got there), add some fire and brimstone
from the nearest volcano, whisk in methane, hydrogen
and carbonaceous smog from the primitive atmosphere and
round off the recipe by zapping the whole concoction with a
blast of lightning and Bob’s your protozoan.
This is what we can perhaps call the Frankenstein scenario.
Other possibilities for the start of life on Earth can be summarized
as the Hot Deep Rocks hypothesis, where life is posited to
have started either underground or around undersea volcanic
vents, rich in nutrients. And then there is the It Came from
Outer Space theory. All have their devotees, all have their
unarguable points and all have serious flaws. They might all be
wrong or, conversely, they might all be right.
Understanding how life started – and how likely it is that we
will find it elsewhere – would be a lot easier if we could decide
just what it is. Living things are made of non-living stuff; there is
no ‘life element’ that always gives a special spark to whatever it
is in. We aremade fromthe same stuff as the rocks and the sea,
the planet Jupiter and indeed the star Alpha Centauri, none of
which, so far as we know, can possibly count as being alive.
So what is it that makes certain jumbles of perfectly normal
atoms and molecules alive and others not? Living things, to
take a purely reductionist view, can be seen as little more than
very elaborate crystals. I remember a schoolteacher of mine, a
very dry man who lived in the worlds of mathematics and
physics, dismissing the whole field of biology as ‘glorified
chemistry’ and chemistry as ‘an unnecessary elaboration of
physics’. Biology teachers say that something is ‘alive’ if it can
move, feed, excrete, reproduce and respond to stimuli. But
the trouble is, this definition is not really a definition at all, but
a contingent description of what we see around us that we
have all agreed is alive.
Does life have to be capable of evolution by natural selection?
Several definitions of life hold that it does, but why? It is
is the universe alive? 105
perfectly possible to imagine a biosphere where the dominant
mechanism of evolution is not natural selection but genetic
drift or some other process. What about artificial organisms?
Several people and firms now seem to be a mere grant proposal
away from creating a truly synthetic life form.
If we did this and directed its evolution, then would it not be
alive? Are viruses alive? They are made of the ‘life stuff’ DNA
and protein, yet they can be crystallized in a petri dish. You
cannot crystallize, say, baboons or snakes. Part of the popular
view of life is that only life can think, yet clearly most of it
cannot, and some things, such as computers, that may be
able to ‘think’ in a limited way (or at least will be able to soon)
are clearly not alive.
So, what is life? One very popular if rather floppy definition
is ‘We don’t know exactly but we will hopefully know life when
we see it’. Defining what we mean by life on Earth is hard
enough, so creating a catch-all definition of life that works
everywhere else (assuming that there is life anywhere else) is
going to be a great deal harder again.
Scientists and sci-fi writers have, after all, postulated life
forms based on all sorts of outlandish chemistries and even
more outlandish types of physics. In their charming book
about the end of time, The Five Ages of the Universe, physicists
Fred Adams and Greg Laughlin dream up an intelligent black
hole called Bob. He is quite plausible. So are the life forms
dreamt up by the gravitational astronomer and novelist
Robert Forward, which are made not of carbon, nor even
silicon, but neutron matter, the famously bizarre stuff of
collapsed stars, a spoonful of which weighs as much as a
battleship.
If life depends on organization and complexity (the possible
seeds of a definition) then it is quite easy to imagine living
beings arising in the magnetized interiors of stars, vast intelligent
entities using the quantum property of entanglement, or
106 10 questions science can’t answer yet
the huge semi-permanent and constantly evolving whorls and
eddies in the atmosphere of a gas giant.
The exciting implications of finding life elsewhere are what
have fuelled the growth of the new discipline of astrobiology,
described by one wag as ‘the only science without a subject
matter’. Astrobiologists are working on the assumption that if
there is life out there we will be able to identify it as such, and it
is astrobiologists who perhaps have the most vested interests in
coming up with a workable and firm definition of what life is.
The suggestion that life is something that we will recognize
when we see it is perhaps not popular with these people. In
December 2006, Robert Hazen, professor of Earth Science at
George Mason University in Virginia, wrote in New Scientist
that ‘I think the chances are good we won’t [my italics] know
alien life when we see it’.
A meeting held in the US that year to discuss the definition
of life came up with answers that ranged from the sublime to
the ridiculous. One expert on lipid molecules argued, rather
parochially, that we must be searching for semi-permeable
lipid membranes (which envelop every cell in the kind of life
we know). Another expert on metabolism maintained that life
began with the first self-sustaining metabolic cycle.
Yet others maintained that some sort of RNA coding was
required, while a geologist sided with my old teacher and
stated that life is essentially no more than a very elaborate selfreplicating
crystal. Some other definitions: ‘Any population of
entities which has the properties of multiplication, heredity
and variation’ (John Maynard Smith, the evolutionary biologist);
‘an expected, collectively self-organized property of
catalytic polymers’ (information theorist Stuart Kauffman).
Vaguer definitions include ‘the ability to communicate’ or ‘a
flow of energy, matter and communication’.
Robert Hazen points out that our total inability to define life
is wholly unsurprising. After all, we have severe problems
is the universe alive? 107
separating the living from the non-living, even when it comes
to our own lives.
The issue of when human life begins in the womb is hugely
contentious and has fuelled endless ethical and religious
debates. A newly fertilized egg is clearly not the same thing as
a baby, but equally clearly any difference between a 35-weekold
foetus and a newborn infant is purely arbitrary. Finally,
most clearly of all, assigning a definite date for the inception of
life risks taking us into ‘magic spark’ territory.
‘At the other end of the human journey’, Hazen says, ‘doctors
and lawyers require a definition of life in order to deal ethically
with patients who are brain dead or otherwise terminally
unresponsive’. A century ago, you were dead when certain
vital signs had ceased: when the heart stopped beating and
when you stopped breathing. Now, in the era of heart–lung
machines, intensive care and the occasional remarkable recovery
from the deepest of comas, death seems to be more of a
process than an event. The best definition we have seems to
be ‘you are dead when the doctors can do no more for you’.
In the end, a definition of life that distinguishes all imaginable
living objects from the non-living ones is extremely elusive. Reliance
on the existence of cell membranes, self-replication and so
on seem to be arbitrary simply because we can all imagine
things which we might all agree are alive and yet which do not
fit these definitions. Gerald Joyce of the Scripps Research Institute
has suggested a ‘working definition’ as simply ‘any chemical
system capable of undergoing Darwinian evolution’.
This definition, which is liked by Hazen, seems to include
everything that we think of as alive, but would exclude things
like computer simulations and machine consciousness, as well
as artificial organisms designed to be incapable of adaptive
evolution.
Maybe there is, in fact, no clear dividing line between ‘clever
crystals’ and what we would call living organisms. Robert
108 10 questions science can’t answer yet
Hazen says his favourite idea is that life on Earth may have
arisen as a thin molecular coating on rock surfaces, a new form
of complex mineral able to spread and grow a little like lichen
(although this was most definitely not lichen) according to the
nutrients available.
Having a decent definition of life will be necessary if we are
to stand any chance of finding it elsewhere. Life could of
course make its presence felt in a very obvious way. But assuming
that little green men, ray-gun-wielding Martians and logical
humanoids with pointy ears are, in galactic terms, thin on
the ground, then we are probably talking about stuff that is a
lot more subtle.
It may turn out, as some suspect, that life is fundamental.
Life may be very, very old indeed, its precursors forming not
long after the beginning of time, long before there were any
planets on which it could get a grip. We may not live in a Star
Trek galaxy, home to thousands of alien races with funny foreheads
and a rather stilted grasp of English, but we may well
live in a ‘slime mould’ galaxy where life, usually of the simplest
of kinds, is staggeringly common.
Richard Taylor, the Secretary of the British Interplanetary
Society, thinks that life may well be so common that there are
at least ten bodies in our Solar System alone which have it.
And if he is right about this – he is certainly not alone in his
opinion – with the discovery that probably half of all stars in
our galaxies have some kind of planetary accompaniment
(this is a statistical likelihood basd on the number of extrasolar
planets discovered in the last dozen years or so), the number
of habitable – and inhabited – worlds in the Milky Way alone
will run into the tens of billions.
Twenty years ago you would have found few scientists willing
to speculate that there could be life elsewhere in our Solar
System. This, before the post-1995 wave of discovery of
extrasolar planets, made the hypothesis that we were probais
the universe alive? 109
bly very much alone a popular one. Now it is a quite commonly
held view that there may be several ‘local’ candidates
for life, and not just Mars, which has long been held to be the
most likely second oasis in the Sun’s family. At least one moon
of Jupiter, a couple of Saturn’s and maybe a whole new class of
objects far beyond icy Pluto may plausibly be home to at least
some sort of microbial life.
It is possible that precursors to life, like Hazen’s rock-coatings,
are common in environments where the suitable chemistry
is available. Not the surface of the Moon, perhaps, but
maybe on Titan, Saturn’s now not-so-enigmatic largest satellite,
where occasional cometary impacts and perhaps rhythmical
climate change allow brief warming periods where such
not-quite-life-and-not-quite-as-we-know-it chemistry could
get going.
Finding fossilized or extant evidence for the precursors of life
somewhere like Titan would be almost as interesting as finding
life itself, for it would set a new boundary – the limits
perhaps of the non-living. Titan has, on its surface, all the ‘ingredients’
(in warm-little-pond thinking) for life – lots of nice
gloopy carbon compounds and water (albeit frozen) – and it is
geologically active, with materials circulated from below the
crust, to the surface, into the atmosphere and down again as
precipitation, just like on Earth. Furthermore, although the
surface of Titan is rather chilly, underground it may be quite
different.
There is just a chance that in our lifetime some sort of conclusive
evidence will be found for life elsewhere in our Solar
System. The most likely place we will find it is on Mars,
although it is just possible that something will turn up either
on Europa, a moon of Jupiter thought to harbour an ocean of
brine beneath its frozen surface, or Enceladus, another satellite
of Saturn which we know has liquid water very close to the
surface (the spaceprobe Cassini has photographed spectacu-
110 10 questions science can’t answer yet
lar geysers erupting from this tiny moon, which is about the
size of France).
Mars remains the most likely place that we will find evidence
of extraterrestrial life in the near future. Of course no one is
expecting little green men or the canal builders of legend, but
recent discoveries from the Red Planet suggest that it may be a
more amenable place, even today, for life than was thought
even when the first space probes arrived in the 1960s.
In the late 1990s, a space probe called Mars Global Surveyor
(MGS), now sadly defunct, sent back images of crater walls
showing apparent ‘gullies’ and ‘alcoves’ a few hundred
metres long and a few tens of metres wide, which the spacecraft’s
imaging team said could only have been carved by running
water. Over the years more gullies were found, together
with thousands of strange dark streaks, all over Mars, that
some said could only be caused by running water in the very
recent past.
Then, in December 2006, an article was published in Science1
showing comparisons between crater walls a few years
apart using photographs taken by MGS. The pictures showed
new gullies sprouting from the cliffs, the suggestion being
that whatever is causing these features is causing them right
now. Cue ‘Water flows on Mars’ headlines and even ‘Has
NASA found life on Mars?’ in one newspaper, holding to the
journalistic maxim that whenever a newspaper headline asks a
question, the answer will invariably turn out to be negative.
Now, it must be said here that a few gullies do not mean that
Mars is inhabited, even by hardy microbes. Perhaps too many
scientists and journalists have rushed to populate Mars with
life on the basis of what remains still rather flimsy evidence. I
am sympathetic to the view of Australian geologist Nick
Hoffman, whose ‘White Mars’ hypothesis states that many of
the features we see on the Martian surface were carved by
carbon dioxide flows rather than water, either now or in the
is the universe alive? 111
distant past. ‘We are in danger of looking at this planet
through blue-tinted spectacles’ he says.
We have, at best, circumstantial evidence that Mars has, or
once had, conditions at or near its surface that would, at a
push, be capable of supporting life for some of the hardiest
micro-organisms currently living on Earth. But despite their
sterling work, it is very unlikely that any of the current generation
of robot space probes in orbit or on the surface of Mars
will discover concrete evidence for life. To do this we will probably
need to get hold of some Martian material and study it
here on Earth or in situ, under the gaze of a human eye.
Actually, we may not need to go to Mars at all to do this.
Mars (and the Earth) are being constantly bombarded by
meteorites, some very large, capable of excavating impact
craters and sending large amounts of Martian or Terrestrial
material into space at escape velocities.
A decade ago there was a huge brouhaha when a meteorite
(given the snappy label ALH 84001), found in the Allen Hills in
Antarctica, was announced not only to have come from Mars
but to contain curious tubular structures that were interpreted
by some as being fossil bacteria. Since then, the verdict has
swayed back and forth on ALH 84001; the balance of opinion
now seems to be that the structures are not necessarily indicative
of life, but no doubt the pendulum will swing back once
again.
What does all this tell us?Well, firstly, if we can show that life
is present, or has been present (the structures in ALH 84001,
whatever they are, were ‘fossilized’ several hundreds of millions
of years ago) on at least one other body in our Solar
System we will have to draw one of two conclusions. One is
interesting, but not a paradigm shift. The other is both. And
the thing is, we may never know which conclusion to draw.
The first conclusion would be that life arose somewhere in
the Solar System and migrated, using the interplanetary
112 10 questions science can’t answer yet
meteor courier system, to other bodies. Maybe, as the Australia-
based physicist Paul Davies has speculated, the original
genesis could have happened on Mars. Only later did life
migrate to Earth.
There is circumstantial evidence that this could be the case.
Mars, being smaller, would have suffered less of the hellish
bombardment that scarred the planets and moons of the
Solar System in its early days (Mars had less gravity and was,
simply, a smaller target). Life would have stood a better
chance of getting a foothold and surviving there early on than
on the (relatively massive) Earth. It is possible also, that with a
thinner atmosphere and less Solar radiation, the early Martian
environment of four billion years ago was more hospitable
than that of the early Earth. If this is the case, then we would
all be, as Davies points out, Martians. The War of the Worlds
would have been won four aeons ago.
Conversely, life could have begun on Earth and spread to
Mars. Or it could have begun on Earth or Mars, and spread
from there to the outer Solar System. If we find signs of life on,
or under, Europa or Enceladus or Titan, we could be conceivably
looking at Martians or Terrestrials. It is also possible
(although unlikely perhaps, given the distances involved and
the frigid temperatures pertaining out there) that life first
arose on, say, Titan, and migrated to Earth. We will only know
if we manage to get hold of one of these aliens and do a DNA
analysis. If we find extant life on Mars and discover that it is
related to life on Earth, it would be a fascinating finding, but it
might not actually say much about what life is, how it arose
and how common it is in the Universe. We would simply be
living in a Solar System full of our cousins.
But say we found life on Mars and, furthermore, discovered
that not only was its genetic material completely unrelated to
that on Earth, but that Martian life didn’t even use DNA at all,
but some completely different chemical. Then we would be
is the universe alive? 113
forced to conclude that life had arisen, independently, at least
twice in our Solar System.
We could then conclude that since the first place we went
looking for it, the nearest likely habitat for life, has undergone
independent biogenesis, and furthermore since this planet is
quite different in fundamental ways from our own, life is probably
not only common but ubiquitous in the Universe.
But there remains a third possibility. That life arose on Earth
not as the result of some sort of cross-contamination with
another nearby planet (or vice versa) but that it arrived in the
Solar System from somewhere else entirely.
The idea of panspermia was first mooted by the Greek philosopher
Anaxagoras, but although long dismissed as unlikely,
it has never quite fallen to the pit of true scientific disreputability.
It states, simply, that life is scattered throughout
space as ‘seeds’ or ‘spores’ which propagate throughout the
cosmos.
A weak version of the hypothesis, interplanetary lithopanspermia
envisages the situation outlined above – that life could
arise, once or more than once, on one planet in our Solar
System and spread to other bodies in the Solar empire carried
on space rocks (or even space probes in which humankind
may have unwittingly sparked panspermia in our own neighbourhood
very recently). A stronger interstellar version posits
that life could spread between star systems using essentially
the same means of transport, bits of rocks blasted off planetary
surfaces during meteor or cometary impacts.
A more profound kind of panspermia holds that life, or its
antecedents, permeates space, perhaps in cosmic dust, or tied
up in the swarms of icy bodies that probably envelop every
star and are scattered in the voids between. The strongest version
of all posits that life is actually a fundamental property of
the Universe, and owes its origins to processes and events that
arose during or shortly after the Big Bang itself. According to
114 10 questions science can’t answer yet
this hypothesis, ‘life’ is every much as fundamental as, say, the
strong nuclear force or the gravitational constant.
Before deciding which, if any, of these possibilities is most
likely to be correct, consider the implications. Firstly, the
panspermia hypothesis does not really answer any questions
about how and when life began. It merely pushes the date of
biogenesis back to before the beginning of life on Earth. It also
does not speculate on whether life arose just once in the early
Universe or many times at separate locations.
One variant of the panspermia hypothesis states that out
there somewhere, intelligent life is deliberately seeding the
cosmos by firing huge quantities of DNA into space. This
again does not solve the genesis problem, and sounds pretty
outlandish, but it has been taken seriously by some serious
scientists, notably Francis Crick, the co-discoverer of the helical
structure of DNA. Panspermia seems, at first glance, to be
an unnecessary elaboration on an already elaborate problem.
But there are several strong arguments for panspermia
which are hard to totally refute. Perhaps the most convincing
‘evidence’ is the extremely short – some say suspiciously short
– time it took life to arise on Earth after it was formed.
Greenlandic rocks of great antiquity, some 3,850 million years
old, have been found containing bounded iron formations
thought to have been released by photosynthetic plants.
Less controversially (these iron deposits could conceivably
have a non-biological origin), stromatolites – fossilized marine
bacterial colonies (living examples can be seen today in Western
Australia) have been found that are 3.5 billion years old.
The point is that the Earth is around 4.55 billion years old, and
it is believed that for the first few hundred million years or so of
its existence it suffered a bombardment by Solar System
debris on a scale millions of times more frequent and violent
than we see today.
is the universe alive? 115
Every few tens of millions of years the Earth would have been
hit by a rock large enough to effectively sterilize it. One
impact, by a Mars-sized object, is thought to have blasted a
huge molten ball of magma into space which cooled and
became the Moon.
The vital thing is that all life on Earth today must be descended
from an organism that came into being after the last
sterilizing event (it is quite possible that biogenesis in fact
occurred several times, each lineage being wiped out by
impactors in this period, appropriately named the Hadean, in
which case our oldest fossils may effectively be those of alien
life forms). This doesn’t give very much time for life to get
going, a few hundred or even a few tens of millions of years at
most. To some, this is implausible. The Universe as a whole has
been ‘life friendly’, in terms of the requisite chemicals being
available, for a much longer time. It is perhaps statistically
more likely, say the panspermians, that the ‘original’ life arose
during this much longer time period than during the rather
limited window afforded on Earth itself.
There is another piece of evidence that counts both for and
against panspermia, and that is the discovery that life on Earth
can thrive in a far greater variety of environments than was
once thought possible. Again, at school, we were taught that
life was pretty much impossible at temperatures over about
60 °C. Hotter than this, and proteins denature and DNA falls
apart. Now we know that some species of bacteria not only survive
but thrive in temperatures hotter than the boiling point of
water, clustered around the deep ocean vents known as black
smokers. Everywhere we look, we find life: deep under the Antarctic
ice and, most importantly perhaps, several kilometres
underground.
There is some evidence (although this is as yet not widely
accepted) that tiny organisms, putatively named nanobes,
may be able to survive 10–20 kilometres underground under
116 10 questions science can’t answer yet
conditions of really quite extreme heat and pressure. Perhaps
most pertinently, viable spores have been discovered in mineral
grains that are hundreds of millions of years old. Life can
not only tolerate high temperatures but extreme pH levels
too, as witnessed by the discovery of micro-organisms which
happily thrive in hot springs of basically sulphuric acid.
And life can cope with very cold conditions too. Deep in the
polar ice sheets a bacterium called Colwellia has been found at
temperatures of –40 °C, and in the lab these organisms have
been found capable of surviving the temperatures of liquid
nitrogen (–196 °C), a finding which Dirk Schulze-Makuch, an
astrobiologist at Washington State University described to
New Scientist in early 2007 as ‘mind boggling’. Until recently
the lower limit for life was thought to be around –30 °C, and
the discovery of psychrophiles, cold-loving organisms, has
come as a real surprise. For a start, it demonstrates the impressive
and elaborate tricks that such organisms have up their
sleeves to prevent the water in their cells from freezing. By
concentrating salt, the freezing point of water drops to
–50 °C. Sticky proteins called exopolymers can prevent the
formation of cell-shattering ice crystals. But just how Colwellia
can not only survive being immersed in liquid nitrogen but
actually appear to metabolize at these temperatures remains a
mystery.
The fact that life can survive at such low temperatures does,
if anything, extend the possible range for life in the Universe
generally far more than the discovery that some like it hot.
After all, much of the Universe is extremely cold, not boiling
hot. Some of the more promising homes for life in our Solar
System are the large satellites of the outer planets where it is
very frigid indeed.
If microbes are happy at –40 °C then suddenly whole
swathes of Solar real estate, including the vast, uncountable
swarm of icy objects out in the Kuiper Belt, beyond Pluto, sudis
the universe alive? 117
denly look far more hospitable (it is thought that the interiors
of these objects may be kept warm by the heat of radioactive
decay, even if their surfaces are 200 degrees below zero or
colder). Forget Richard Taylor’s 10 possible homes for life; the
true number of places where microbes could eke out a living
in our Solar System alone may run into the hundreds or thousands.
The discovery that life is more robust and adaptable is, at
one reading, evidence against panspermia, as it suggests that
we may need to examine a far greater range of possibilities for
the location of biogenesis on Earth than we thought. It may
well be the case, for instance, that we will have to rethink the
assumption that during the first few hundred million years of
its existence the Earth was uninhabitable; if bacteria can survive
20 kilometres underground it is possible that life could
have clung on even during the most severe batterings of the
early Hadean. The existence of the extremophiles also muddies
the water considerably when considering what is to be
thought the ‘normal’ habitat for life on Earth; is it on the surface,
in the oceans and in the air as we (and Darwin) thought,
or is there a hugely bigger hidden biosphere underground, in
the rocks and buried deep in the sediments, under the ice or in
the upper reaches of the atmosphere? Did life evolve on the
surface and migrate downwards, or did it evolve underground
and move up when the skies cleared? Did life possibly evolve
in the sky? We may never know.
But while extremophiles seem to suggest that it may have
been easier for life to get a hold on earth in its earliest days,
they also point to the possibility that life – microbial life and
spores – is robust enough to survive the rigours of interplanetary
and even interstellar space, as the panspermia hypothesis
suggests. The cold of space holds no barrier when a microbe
which evolved on the balmy Earth can continue functioning at
–200 °C.
118 10 questions science can’t answer yet
This is all circumstantial evidence for panspermia, however
(just as it is circumstantial evidence to posit that because some
microbes could live on Mars then microbial life will by dint
have evolved there). Do we have any reason to believe that life
actually has arrived on Earth?
The champions of modern panspermia were the late Sir Fred
Hoyle and his colleague Chandra Wickramasinghe, now at
Cardiff University. As well as being Big Bang sceptics, Hoyle
and Wickramasinghe held that not only had Earth been
seeded by life from space billions of years ago, but that active
spores continue to rain down upon the planet today. This
could explain, they said, the often mysterious epidemics that
plague humanity. Around 40,000 tonnes of carbonaceous
material fall onto the Earth each year from space, and Hoyle
maintained that about a tonne of this was in the form of actual
bacteria or bacterial spores. In 2003, during the height of the
SARS epidemic in Asia, which killed several hundred people,
Wickramasinghe wrote to The Lancet medical journal claiming
that the virus responsible was possibly extraterrestrial in
origin.
This belief – and it is a belief, and a fringe one at that – stems
from the discovery that complex organic (carbon-containing)
compounds are common and exist in large quantities and
great variety in a number of (on the face of it) rather unpromising
cosmic objects, most notably comets. Astronomers have
detected, using spectroscopy, many kinds of organic molecules
in space, floating in clouds of gas or bound up in dust
particles. They range from simple compounds like methane,
hydrogen cyanide and alcohols, including ethyl alcohol, to
more complex molecules, such as amino acids, of which more
than 70 have been found in meteorites.
An experiment performed by NASA in 2001 attempted to
replicate the effect of a comet, loaded with amino acids (the
building blocks of proteins) slamming into Earth at thousands
is the universe alive? 119
of kilometres an hour. Rather than fragmenting the amino
acids, as was assumed would happen, the impact (using a sort
of high-velocity bullet) turned out to actually force the amino
acids to link together to form peptide chains, polymer compounds
just one stage less complex than proteins themselves.
In fact, a class of compound called nitrogenated aromatics
has been found just about everywhere we look in space: in
comets, in interstellar dust clouds, and in the atmospheres of
the outer planets. These compounds – carbon-based molecules
based on a ring structure – are, generically, the building
blocks for life, forming the basis for complex biological compounds
such as proteins and nucleic acids.
In February 2004, Professor Sandra Pizzarello and colleagues
published a paper in Science2 in which she argued that the
chirality – the tendency for the molecules to be left- or righthanded
– of proteins and sugars in Earth life could be linked to
the meteoritic material which has hit our planet over billions
of years.
A class of meteorite called carbonaceous chondrites contains
the most complex carbon compounds known from outside
Earth, including amino acids (the building blocks of
proteins) and sugars. Pizzarello found that in experiments
where sugar synthesis was performed in the laboratory under
conditions thought to have pertained on the early Earth, a
constant rain of chemicals of the right (or in this case, literally,
left) ‘handedness’ caused the ‘native’ sugars to change
their chirality. This does not mean that Pizarello has proved
that life arrived on meteorites, but that it is at least possible
that the arrival of meteorites might have had a profound
influence on the evolution of that life, however it got started
on our planet.
We know that these organic molecules have been present in
the Universe for a very long time, certainly predating the existence
of the Earth. A prime candidate for the ‘oldest thing on
120 10 questions science can’t answer yet
Earth’ is a meteorite which slammed rather dramatically and
very visibly into Lake Tagish in Canada in 2000. In 2006,
details of the analysis of the Tagish meteorite were released in
Science3, revealing that the grains from which it is composed
predate even the formation of the Sun. Hollow carbon spheres
found in the meteorite fragments, each a few thousands of a
millimetre across, were speculatively dated as being several
billions of years older even than the 4.6 billion years of our
star. It is possible, in other words, that contained in this rock
fragment are particles almost as old as the Universe itself,
containing complex compounds, including amino acids,
interleaved with clay mineral grains.
The clay minerals, silicates arranged in layers, are (it is speculated)
possible ‘wombs’ in the formation of some sort of prelife
entity, maybe complex self-replicating proteins or the precursors
to nucleic acids. Commenting on the finding, one of
the investigators, said: ‘These things tell us what kinds of
chemicals are out there in interstellar space. They could have
been the original seeds for life to get started’.
The idea that life, or at least the chemical precursors to life,
could have arrived on the Earth carried by cometary material is
no longer regarded as outlandish. Comets are deeply mysterious,
part of a class of ubiquitous icy objects that may envelop
every star system and form on the edges of interstellar clouds.
Comets and their relations in the Kuiper Belt may be ambassadors
from a time long before our Solar System was formed.
The discovery of complex organic chemicals on meteoritic
fragments strongly suggests that at least some of the processes
once assumed to have taken place in Darwin’s warm
little pond may instead have occurred in deep space, at a time
when the Universe was still young.
This is what we know; from now on all is speculation. As far
as ‘evidence’ for more complex life forms on distant planets,
discussions of UFOs and their inhabitants belong somewhere
is the universe alive? 121
else. But it is possible to speculate nonetheless on scenarios
that are just as weird and wonderful as flying saucers. If life
really owes its origins to a time in the very early history of the
Universe, does this suggest that life is possibly an intrinsic
property of our cosmos?
On the wilder shores of the panspermia community it has
been suggested that life may itself form part of the ‘organizing
principle’ of the Universe, with its origins in the Big Bang itself.
This can be seen as an extension of the ‘Gaia’ concept, advocated
by the British biologist James Lovelock, which states that
living and non-living processes on Earth are locked into a
series of feedback mechanisms. In other words, the Earth is
like it is because of the life that is on it, as much as the other
way round.
In an article in Nature4, in 2004,William Dietrich, of the University
of California at Berkeley, speculates what the Earth
would be like if it had never had life. ‘Very little has been written
about the evolution of Earth in the absence of life’, he
writes. He goes on to speculate that life on Earth may have
had far more profound effects that simply altering the composition
of the atmosphere (pumping in oxygen via photosynthesis)
and the formation of fossiliferous rocks:
On Earth, plate tectonics depends on an upper mantle’s
low-viscosity zone on which plates can glide, and it has
been proposed that this zone arises from the injections of
water at subduction zones.... Is it possible that the emergence
of life on earth prevented the development of
atmospheric conditions favourable to solar wind erosion,
keeping the planet ‘wet’ and enabling plate tectonics? Is
plate tectonics on Earth a consequence of life on Earth?
If this hypothesis is right, it would be an extraordinary thing
to say about our planet. Life may have saved the Earth from
122 10 questions science can’t answer yet
turning into another Venus: by squirrelling away gigatonnes
of carbon dioxide in their shells, countless quadrillions of tiny
sea creatures could, over the aeons, have prevented a massive
CO2 build up in Earth’s atmosphere and a consequent runaway
greenhouse effect, which seems to have been what happened
on Venus. Earth could then really be considered,
without any of the perhaps unfortunate spiritual overtones
generated by the original Gaia concept, a ‘living’ planet, a
biological system, with the same relationship to the organisms
that live on and in it as a shell to the snail within.
Could the Universe be like this, its properties at least partly
influenced by the presence of life? Certainly, on a very fundamental
level the anthropic principle states that the Universe is
a ‘Goldilocks universe’, fine-tuned to be just right for life. The
physical constants, the nature of matter and the particles and
so on seem to be set up in such a way that they allow life to be
viable, and – the important bit – it seems there is a very narrow
‘window’ outside which we would certainly be looking at a
lifeless universe.
The physicist Lee Smolin proposed a theory back in the
1990s that one possible origin of the Universe – that it arose as
a bubble of space–time in another universe created by a black
hole – suggests that life-friendly universes may be subject to a
form of cosmic natural selection; in short, universes which are
capable of producing the maximum number of black holes
would be the most productive ‘parents’, and it is the case that
a universe set up to produce black holes (lots of stable stars of
the right size and mass) are also universes where the physical
constants permit ‘our’ sort of life to exist.
This theory suggests that life, if not an intrinsic property of
the Universe, is at least central to our understanding of why
the world around us is as it is. The exciting thing is that so
much of this is testable. We can search for evidence of life on
other planets and in the debris and detritus that hits the Earth.
is the universe alive? 123
If the Universe does turn out to be alive then it would, in philosophical
terms, not only be an outstanding discovery but it
would also turn the heat off humanity a bit. We may never
know how frequent intelligent life is, but at least we would
know that should we inadvertently bring about our own
demise there would be an awful lot of places out there where
the great life project would carry on. That warm little pond
may have been a very big sea indeed.
References
1 Malin, M. C., Edgett, K. S., Posiolova, L. V., McColley, S. M. and
Noe Dobrea, E. Z. (2006) Present-day impact cratering rate and
contemporary gully activity on Mars. Science, 314, 1573–7.
2 Pizzarello, S. and Weber, A. L. (2004) Prebiotic amino acids as
asymmetric catalysts. Science, 303, 1151.
3 Nakamura-Messenger, K., Messenger, S., Keller, L. P., Clemett, S.
J. and Zolensky, M. E. (2006) Organic globules in the Tagish Lake
meteorite: remnants of the protosolar disk. Science, 314, 5804.
4 Dietrich, W. E. and Perron, J. T. (2006) The search for a topographic
signature of life. Nature, 439, 411–17.
124 10 questions science can’t answer yet
7
are you the same person you were a
minute ago?
125
What a silly question. Of course you are. You have the same
skin, the same bones, the same meat. More importantly,
because of course we are talking about your mind here, the
essence of your good self, you have the same brain: the same
(more or less) neurons, the same synapses, the same blood
vessels and connective tissue inside your skull. More profoundly,
you have the same memories. And unless something
alarming happens to you, like an almighty thwack on the
head, you have the impression of an unbroken continuum of
consciousness.
But the more you think about it, the more you realize that
you are not the same person you were even a second ago.
You may be composed of the same atoms, but only approximately.
In one minute, for example, you will metabolize
about 4.5 grams of oxygen – that is one quadrillion atoms or
thereabouts every 60 seconds. Several trillions of carbon
dioxide molecules leave your lungs and trillions more will be
assimilated from the products of digestion. In short, the cellular
chemistry that makes you tick is a constant merry-goround
of breakdown and synthesis. On a molecular and
atomic level you are not quite the same person you were a
minute ago.
Forty years ago I laid claim to about 10% of the mass that I
am now and more or less every atom in my body has been
replaced since then. In another 40 years’ time, if I make it that
far, I will be similarly different from today. And it is not just the
material structure of my body that changes, every year, every
hour, every second. I am moving, constantly and unstoppably.
If I sit as still as I can I am still rotating at about 450 mph
around the Earth’s axis, and at 66,000 mph around that of
the Sun. Every microsecond I occupy another wodge of
space–time. My makeup and position is changing all the time.
If ‘I’ have any definition it is that I am an indeterminate bag of
flesh and bones that walks around claiming to be me.
126 10 questions science can’t answer yet
The concept of self, and the continuity of existence, is an
old philosophical chestnut. At its root is the thorny issue of
consciousness, the mysterious feeling of self-awareness that
remains totally unexplained. The practicalities of identity are
something that we think about more than ever before. This is
an age when governments, in the dread ‘interest of security’
want to fingerprint us, photograph our irises, and barcode
our ‘biometric’ data and add this to a database containing
our every movement, caught on CCTV and trawls through
cyberspace.
In a banal way, our identities are thus reduced to a stream of
numbers. With the advent of high-speed Internet access, millions
of people are establishing second, third and more identities
in the online world, something that has been endlessly
predicted since the advent of the Internet 30 years ago and
yet which is only now starting to come true.
Millions of people now have ‘lives’ in electronic worlds like
Second Life, and spend considerable amounts of time, effort
and money pretending to be someone else and living an artificial
life. It is easy to see this trend continuing and these alteregos
proliferating.
Back to reality. Establishing a concept of identity matters in
so many ways. Courts, as never before, recognize the truth
that the person before them, while sharing the same body,
may not be the same person who committed the crime. Madness,
physical illness and profound injury may intercede to
create a new person. That much has been recognized for a
long time. But the more science gains an understanding of
what the mind is (which admittedly isn’t much of an understanding
as yet), the more we are forced to consider the possibility
that the continuity of existence is a fiction.
Nowadays, a schizophrenic who kills is excused prison on
account of his condition. How long before a man, caught for
a crime he committed 40 years ago in his teens, might
are you the same person you were a minute ago? 127
reasonably argue that he is simply not the same person that he
was then and thus also escape punishment? Pinning down
what we mean by identity has profound implications for the
way we treat criminals or the elderly, and for how we think
about ourselves. What light can science shine on the matter?
And does establishing what we mean by identity and self have
any relevance to the ‘hard’ consciousness question?
There are two basic views on identity. One, the ‘folk science’
view, holds that there is an ‘inner essence’ of personhood, an
‘ego’ that is constant throughout time. This is the way most of
us think about identity. I am the same person I was as a child
and I shall continue to be the same person until the day I die.
Yes, my body changes but some sort of ‘essence of me’
remains constant. The problem, comforting and coherent as
the ego theory is, is that it cannot be true. Not literally.
The alternative idea, that we are a ‘bundle’ of mental states,
tumbling down time’s motorway like a tumbleweed blowing
in the wind, offends just about everything we think to be true
about ourselves. We are not what we believe ourselves to be.
Our lives are a series of related experiences, but there is no
single entity at the centre actually having these experiences.
This is a disturbing, even distressing, viewpoint. It says that
there is no real self. That continuity of existence is an illusion
(although the consciousness of those experiences is not).
Before we can consider just what it is that is generating this
experience of endless ‘nows’, we need to put the old ego
theory to rest and kill the ghost in the machine.
The problem with a ‘soul’ is that we need to describe what it
is, how it arises and how it interacts with ordinary matter, i.e.
the cells of our brain. There is no way of doing this and no evidence
for the existence of such a phenomenon. Science now
rejects the idea of the soul, on the basis of Occam’s razor as
much as anything. Rather than believing that a soul (for which
we have no evidence) uses the brain for thinking, it is far
128 10 questions science can’t answer yet
simpler to believe that it is the brain itself that is generating
the experience of those thoughts.
A telling illumination on what the folk science concept of self
actually means was made by the philosopher Derek Parfit. In
his 1986 book Reasons and Persons he dissects the commonly
held notion of the self with a series of neat thought experiments
involving teleport machines. Teleporters, like time
machines, are useful devices, not just as fun sci-fi plot devices,
but because even before anyone has built one and switched it
on they can be used to perform all sorts of interesting mind
experiments.
The classical sci-fi teleport machine works in one of two
ways. In the first, the object to be teleported, say a human
being, is somehow transported in toto through the ether to
her destination. These machines make use of exotic structures
like wormholes, able to warp and bend space to allow instantaneous
travel from point A to point B. While interesting, these
teleport devices do not pose interesting philosophical questions.
They are, essentially, trucks, albeit very exotic and clever
ones, because the essence of what is being transported is not
interfered with in any way during the process, any more than
if you were to take a trip by aeroplane.
The interesting questions arise with the other sort of teleport
machine, the sort that takes you to pieces and then reassembles
pieces exactly like those original ones somewhere else.
No one knows whether it is possible to construct such a
machine (in fact there is some experimental evidence that
building a teleporter should be considerably easier than a time
machine), but the feasibility of such a device is not important
to our thought experiment.
In one scenario, you step into the teleport booth and your
body is scanned with exquisite precision. Each of your 7,000
trillion trillion atoms needs to be plotted, by type and position.
It is not clear how this could be achieved. Possibly some
are you the same person you were a minute ago? 129
sort of refinement of the X-ray crystallography technique. The
machine also needs to know the precise quantum state of
every particle. Recent experiments, where whole atoms have
been successfully teleported across a room, suggests that
should a teleport machine capable of handling larger objects
such as a person be possible, it will probably be impossible to
complete this scanning (and subsequent transport) without
destroying the ‘original’. Hopefully, the scanning process
would be near instantaneous and painless.
Then the information gleaned by the scanning machine
must be transmitted to the destination. Again, experiments
suggest that this may be possible using one of the stranger
beasts in the quantum menagerie, the phenomenon of entanglement.
This allows the properties of one particle to be transmitted
an arbitrary distance instantaneously. This seems to
break all sorts of laws, not least the commandment which says
that thou shalt not travel faster than light, but physicists insist
that they have all the bases covered. It can be done, for entire
atoms at least, as proved in 2004 by Professor Rainer Blatt in
Austria and his colleague Dr David Wineland in the US, who
managed to teleport entire atoms across the lab.
There are several possible scenarios explored by Parfit and all
have disquieting implications. If the teleport machine works as
it should, a precise copy, complete with your memories, walks
out of the receiving booth. The original is destroyed. Most
people would be happy to say that the machine has ‘worked’
– that the original ‘you’ has indeed been moved from A to B.
But it is when the machine is tweaked, or malfunctions,
that it becomes clear that something quite profound is
being illustrated. Say the machine makes two copies. Which
one is ‘you’? Say the original ‘you’ is not destroyed. Who
can lay claim to the ownership of your ‘essence’? Once you
start thinking about this you conclude, as Parfit does, that
teleportation is murder. These machines are simply making
130 10 questions science can’t answer yet
replicas. But then you can also go on to conclude, as Parfit
does, that this doesn’t matter. The new you is not an impostor
even though the old you is dead. There is no paradox here
because the old you is being destroyed, in your own brain, all
the time anyway.
Enough of teleport machines and back to the real world.
Say, for example, you have a terrible road accident. In the accident
you receive a bad head injury, so bad that for a few minutes
your brain function drops to nearly zero. But luck is on
your side. The inflammation subsides and the surgeon is
good. Damage is minimized. Nevertheless you spend several
weeks in a profound coma. You have no waking thoughts. You
do not dream. Magnetic resonance imaging shows your brain
to be just meat. Live meat, but not thinking meat.
Happily, your body rallies round. Blood vessels regrow, synapses
start to fire. A month or two later you wake up. For some
time you are not yourself. Your memories are patchy. You have
trouble remembering some facts about your life, but your
memories return. Helped by friends and family you painstakingly
reconstruct your past, filling in the gaps in the narrative
of your life. Within a year you are well enough to return to
work; within two, save for some nasty scars, you are effectively
back to normal.
Or imagine another accident. In this case, a real one, which
happened to a real man, one Phineas Gage. He was working
on a railway construction site as a foreman in 1848. He was
part of a team setting explosives to blast a way through a
rocky outcrop. Something went terribly wrong and a piece of
metal tool a metre long and weighing more than six kilos was
driven by the dynamite through his skull and frontal lobes, the
key bits of grey matter at the front of his brain.
Everyone assumed he was dead, but by some strange happenstance
he was not. Better still, he made a more or less full
recovery. But something was not the same. Accounts vary,
are you the same person you were a minute ago? 131
and recently some doubt has been thrown on this story, but
there are claims that Gage had a fairly dramatic change in his
personality. His intelligence and his memories were largely
intact. Yet according to his doctor and family, the formerly
hard-working, mild-mannered and temperate man became
prone to bouts of drunkenness and bad temper.
Finally, something altogether more mundane: sleep. You
drift off at the end of a long day – a perfectly natural process
that involves neither teleport machines, horrible road accidents
nor metre-long metal spikes. Within minutes you have
entered another world, the world of the sandman. Sometimes
you dream, sometimes you do not, but you are not conscious,
at least not in the way that you are during the day. You have
not, unless you are very lucky, any wilful control over either
the subject or direction of your dreams. Your brain, while not
in the profoundly altered state that is the coma, is nevertheless
not ‘itself’ while you are asleep. ‘You’ effectively switched
yourself off for a few hours, for purposes that are still not
entirely clear. When you awake you of course have all your
memories, atoms and so on.
These examples throw up a profound riddle about the
nature of our existence. What does it mean to be ‘me’? And
what do I mean by the continuation of my identity?
The teleportmachine has to destroy you tomake a replica, but
that replica has identical memories to the original. Imagine, in a
final twist, that the teleportmachine makes a copy, but in exactly
the same place as you were when you stepped in. Furthermore,
the destruction–recreation process takes an extremely short time
– a few trillion-trillionths of a second – far shorter than the time it
takes anything to happen in an intact brain. You have effectively
been killed and rebuilt in less time than it takes a photon to cross
the diameter of an atom. Would you notice?
Phineas Gage was a changed man, but he inhabited the
same body. When you sleep you turn off part of your brain,
132 10 questions science can’t answer yet
which is then revived in the morning. What is the difference
between this and teleportation? When you suffer from Alzheimer’s,
you lose memories. Are you losing the essence of self?
And most people have forgotten anything that happened to
them in the first few months of their existence. Does this mean
that they were a different person then?
To see how slippery identity can be, consider the case of
false memories. If there is an essence of identity it is our memories
which come closest, but it is quite possible, inadvertently
or deliberately, for people to acquire memories of events
which never happened.
Several studies have shown how easy it is to create false
memories. In fact, many of our memories are ‘false’ in that
they do not accurately represent real events which could be
corroborated by witnesses. Most people have memories of
childhood happinesses and traumas that may be confabulations
generated by real memories and later descriptions by
our parents.
Just how easy it is to implant false memories has been shown
by several scientists, most famously the American psychologist
Elizabeth Loftus. In the 1974 ‘Reconstruction of Automobile
Destruction Study’ Loftus showed that an eyewitnesses
memory can be easily altered by information supplied to them
after the event.
Student volunteers were shown film of car accidents and
asked to write reports on what they had seen. Specifically, the
students were asked to gauge the cars’ speed after being
asked the question ‘About how fast were the cars going when
they [verb] with each other?’ The missing verb was either ‘collided’,
‘smashed’, bumped’, ‘hit’ or ‘contacted’. They found
that the ‘faster’ the verb used to describe the collision the
faster the reported speed. Collisions where the cars ‘smashed’
were estimated to have taken place nearly 8 mph faster than
ones where the cars merely ‘contacted’.
are you the same person you were a minute ago? 133
A second study was done, and this time after being shown
the collision the students were asked to say whether or not
there was broken glass at the scene. The more ‘rapid’ the verb
used by the experimenters to describe the collision, the more
likely the students were to ‘remember’ seeing smashed glass
(in fact there was none). When the verb ‘smashed’ was used
more than a third of the volunteers ‘remembered’ seeing glass
that wasn’t there.
The importance of these findings is clear. Most obviously
there are ramifications when it comes to court evidence and
statements given by witnesses to police officers. It is now
accepted that being an eye-witness to an event is no guarantee
whatsoever of accuracy. It is also clear that the way any
question is phrased, by a police officer or a barrister, say, can
have a profound effect on what we ‘remember’.
Falsememory syndrome (FMS) is an even more profound distortion
of ‘self’ than simply misremembering a car accident.
FMS describes a state of mind in which ‘sufferers’, if that is the
word, have vivid but entirely inaccurate memories of childhood
trauma, most notably sexual abuse. The accusation is made
that some professionals, hypnotists and psychologists suspicious
of child abuse unwittingly ‘implant’ such false memories
in their patients, with disastrous consequences. The patients
may now believe that they had been abused by a parent, resulting
in families breaking up and people going to prison.
In the 1980s and 1990s, a series of cases made the headlines
in North America and in Europe where large numbers of
adults were accused of engaging in ritualistic or satanic sexual
abuse of children in their care. Although child sex abuse is distressingly
common, satanic abuse is not. Nevertheless, the
numbers of people affected ran into the hundreds and a lot of
people were incarcerated.
In the enquiries, court cases and lawsuits that followed, the
extraordinary and disturbing lengths to which some social
134 10 questions science can’t answer yet
workers and psychologists would go to implant memories in
young minds was revealed. The trauma of the accusations,
which often led to the break-up of families and wrongful
prosecutions has been well documented; what has been less
well documented is what amounts to the destruction of the
self for some of these children. Individuals with happy memories
of their parents and loved ones have been replaced by
unhappy individuals who ‘remember’ horrid events which
did not happen – disturbances to the self which remained
in place even after the falsehood of the claims was revealed.
In some senses, new individuals have been created out of
nothing.
Less serious is the strange phenomenon of alien abduction.
It is hard to know just how many people now believe that they
have been abducted by aliens, taken aboard their spacecraft
and subjected to often humiliating medical experiments, but
some estimates put the numbers well into the hundreds of
thousands or more. One survey suggested that 1% of the US
population (3 million people) are convinced that they have
been abducted – an extraordinary statistic if true. This is not
a uniquely American phenomenon, but Americans certainly
dominate the lists of abductees.
Sometimes people have continuous, unbroken memories of
experiences which include alien abduction. Far more often,
the abduction event is ‘revealed’ through the medium of therapy
or hypnosis. The experience is seen by many as key to
understanding whatever neurotic conditions may be troubling
them, and therapists assure them that the recollection of
being ‘taken’ is cathartic and therapeutic.
Of course, we have no evidence that any human being has
ever been abducted by aliens, so we must assume that these
recollections are bogus – either these people or lying, or they
have had memories – false fragments of self – implanted by
their therapists.
are you the same person you were a minute ago? 135
What is really interesting is that the inauthenticity of these
memories doesn’t seem to matter. At the American Association
for the Advancement of Science’s annual meeting in
Denver in 2003, Harvard psychologist Richard McNally presented
findings that showed that people who believed they
had been abducted by aliens suffer ‘real’ symptoms such as
disturbed sleep patterns, ‘underscoring the power of emotional
belief’.
Many of the ‘abductees’ have a lot in common – such as a
whole host of related ‘fringe’ beliefs: past lives, astral projection,
tarot cards, the occult and so on. McNally calls this a
‘common recipe’. Many also have episodes of sleep paralysis
and hallucinations, which are often what prompted them to
visit a therapist in the first place. It was these therapists who
usually suggested alien abduction as an ‘explanation’ for their
symptoms.
These recollections became real.War veterans who have suffered
traumatic experiences on the battlefield show characteristic
physiological reactions when shown footage of combat.
Their heart rates go up, they sweat, and they breathe faster
and more shallowly. People who have not experienced combat
do not show the same responses. But ‘alien abductees’
show at least the same responses – increased sweating and
heart rate and so on – as Vietnam vets when told tales of being
abducted and having unpleasant experiments performed
upon them aboard alien spacecraft.
The nature of identity, particularly the continuation of identity,
is in fact a classic philosophical problem that has been
debated at some length. In ‘The Possibility of Altruism’, the
philosopher Thomas Nagel points out: ‘The idea of a temporally
persistent human being is an exceedingly complicated
one’. It leads to other dilemmas. What weight should we give
our future and past selves? Should we treat them as separate
entities and indeed treat one better than the other? It seems
136 10 questions science can’t answer yet
strange to ask this question, but in fact most of us do make a
distinction between them.
As Nagel says, we should have reason to regret our bad
behaviour at the office party last night, not just because the
unfortunate possible consequences now and in the future, but
also because the bad behaviour was bad then per se.
The person who you were then has become the person you
are now, and that regret is a link between the two. Similarly,
we should take account of our future life in a similar way to
how we would consider the life of a different person. By deciding
to take up smoking, or allowing myself to become a drug
addict, I may be said to be causing harm to a future ‘me’ that
is not really the me of today. The first cigarette will not kill me,
nor the first injection of heroin, but in 20 years’ time the
person who calls themselves me may have cause to regret the
decision made by me now. Becoming addicted to nicotine is
thus less like suicide than murder.
That is the philosophy, but what about the science? As
we have seen, the idea of continuous unbroken identity
makes little sense unless you invoke some sort of ghost in the
machine, an old-fashioned soul. But we have no evidence that
this is the case. Instead, there is no ‘self’, just a series of patterns
of information which can be created and destroyed over
and over again. Paul Broks, a psychologist at Plymouth University
in the UK, wrote in New Scientist in 2006, ‘There is no self
to destroy. The patterns are all’.
This leads to what Broks calls a ‘neat inversion’ of conventional
thinking. ‘Those who believe in an essence, or soul, suddenly
become materialists, dreading the loss of an original
body [say in a teleport machine]. But those of us who do not
hold such beliefs are prepared to countenance life after bodily
death’.
Even without the trauma of hypnotically induced false memories,
serious brain injuries or the altered states created by cerare
you the same person you were a minute ago? 137
tain narcotics, all of us will have had at least two ‘selves’ in our
lives. In February 2007, Patricia Bauer of Duke University presented
findings to the AAAS annual conference in San Francisco
that suggest that human infants have a totally separate
‘self’ from their later adult forms. The phenomenon of ‘infant
amnesia’ is puzzling; why are the vast majority of people completely
unable to recollect any events in the first year or so of
their lives? One explanation is that infants are simply unable to
lay down memories. But Bauer has shown, by attaching electrical
sensors to the infants’ scalps to record their responses to
sounds and pictures, that infants do form memories in their
first year in much the same way as adults. The infants in the
study were able to recall events over periods of days or even
months. But because of the immaturity of their brains these
memories evaporate, uncommitted to long-term storage; the
old self is lost and a new one is born.
The realization that the self is not immutable has practical as
well as philosophical implications. Once we are free of the
shackles of the soul, we are also free of having to think about
the self as an inviolable entity. Seeing how easy it is for memories
to be created (by suggestive therapists and lawyers) and
destroyed (by illness or trauma) should make us sceptical of
any account of any controversial event such as a crime, where
accuracy is, or should be, all.
Not only are our selves dying and being reborn every
second due to the normal processes in our brains, they are
also being augmented, sculpted and remade by the people
around us and by our own agency. Now that it is clear just
how easy it is to implant traumatic memories in the minds of
children, we see far fewer families broken up after unfounded
and false claims of ritual abuse than was the case 20 years ago.
Our self is not only being broken and constantly remade, it is
also now clear that it cannot be distinguished from the selves
of others as clearly as was thought, meaning that it is really
138 10 questions science can’t answer yet
true that no man is an island. In the 1990s, it was discovered
that certain brain cells, called ‘mirror neurons’, were present
in the brains of primates (and probably also humans and
birds). Found in the ventral premotor cortex, these cells fire
when monkeys perform certain tasks and also when the
animal watches another perform the same task. Functional
MRI scans of human brains have shown similar systems in the
human brain.
What does this mean? It means that the brain is constructing
a model of the ‘self’ that is in some way outside of itself. Mirror
cells allow one ‘self’ to create a ‘bridge’ to another. Mirror cells
have been implicated in the development of language, and
also in the development of social networks.
Mirror cells have also been implicated in the development of
a theory of mind, knowing (or guessing) what another is
thinking. It is possible that a deficiency in the mirror cell
system could be responsible for autism, as autists seem in
many cases to lack a theory of mind. Some researchers have
even suggested differences in the mirror neuron system
between men and women, backing up the oft-quoted (but
little justified) assertion that females are blessed with greater
empathetic skills than men.
Not only are our selves transient, mobile and destructible,
but there seem to be more than one of them. The neuroscientist
Antonio Damasio says that our sentience can be
divided into a ‘core’ self that reacts to stimuli, building a picture
of the ‘now’ in the brain, and a more reflective ‘extended’
self, which relies on memories and building a picture of an
anticipated future. Disturbances to the mechanisms that give
rise to these selves can have profound consequences. Dementia
can wreck the extended self, while brain injuries (such as
that suffered by Phineas Gage) can disrupt the primary self,
leaving memories intact but, in the words of Paul Broks,
‘recalibrating the machineries of emotion and temperament’.
are you the same person you were a minute ago? 139
Insights into the nature of the conscious mind come from illness.
People suffering from transient epileptic amnesia may
lose their extended self and become a floating mass of awareness
with no identity. People whose brains have been damaged
by stroke may lose all sense of personal identity and yet
be fully conscious and in some senses functioning.
We are not the same as we were a minute ago, in this sense
science does have an answer to this question.We are not even
the same from one bit of our brain to the other. Our selves are
hugely defined by our memories and yet these can be as false
as a childhood storybook.
But this does not mean we are really anywhere near solving
the fundamental problem of explaining self-awareness. The
more science probes the brain, the more it becomes clear that
our ‘folk science’ ideas about self and identity will have to go
out of the window. So might the whole concept of ‘spooky’
consciousness, which may have to go the same way as
phlogiston and the philosopher’s stone. Once it is understood
how physical neurological processes generate a feeling of selfawareness,
then the need to invoke this mysterious entity will
disappear. The most obvious practical implication is that we
may one day have to think rather differently about how we
treat our criminals. The legal concept of lifetime responsibility
may have to change.
Losing the soul sounds like a depressing thing, another victory
for cold reductionism. But in another way it is liberating.
We really can live for the moment, because we have no
choice.
140 10 questions science can’t answer yet
8
why are we all so fat... and does it
really matter?
141
The current epidemic of obesity is one of the most extraordinary
phenomena in the history of human health and wellbeing.
If there is one reason why I am not the same person I
was a month ago, it is because of the inevitable addition of a
few unnecessary grams to my person. The reasons for it
appear obvious and the solution equally so.
But in subtle ways, the plague of fatness defies logic and
divides nutritionists, doctors and the overweight themselves.
Like animal consciousness, this has become far more than a
purely scientific question. It touches on morality and politics
as well. The obesity crisis has spawned dozens of crackpot theories
and fads, and made as many fortunes for those willing to
exploit the misery of the overwhelmed hordes. Meanwhile
our technology, globalized culture and media generate ideals
of human perfection and beauty that would have made Helen
of Troy blush and check for cellulite.We are fat people living in
a world made for the thin.
The statistics (if of course you believe them) are simply
mind-boggling. There are now more people alive eating
themselves into an early grave (a billion overweight, one estimate
said in 2006) than who do not have enough food to live
(800 million suffering from malnutrition). In some parts of the
world the seriously overweight comfortably outnumber the
svelte and even the mildly chubby. America, with 30% of its
population obese, is often cited (discounting island oddities
like Samoa and Tonga) as being the global capital of fat. And
the rest of the world is catching up.
In the UK, two thirds of all adults are now classed as overweight
and a full quarter obese. In Scotland, a greater percentage
of children now are obese even than in the US.
Most startlingly, child and adult obesity rates across a
number of countries, including the US, Canada and much of
Western Europe, have tripled or quadrupled in the past 30
years or so. One 2006 Department of Health survey predicted
142 10 questions science can’t answer yet
that by 2010 there will be 12 million obese adults and a million
obese children in the UK. By the middle of the century, if
current trends continue, nearly everyone in the US will be overweight
and a majority of the population clinically obese. Obesity
rates are soaring across Asia, South America and even
Africa (although malnutrition, not overfeeding, remains that
continent’s biggest problem).
And with obesity comes a whole host of known problems
and side-effects; some entirely predictable, some less so.
Being very overweight has an obvious negative effect on quality
of life. Serious conditions such as heart disease and diabetes
are more common in the obese. Being hugely overweight
is bad for you.
This tidal wave of fatness is affecting the very shape of our
world. Everything has to be slightly bigger than it was even a
quarter of a century ago. Bus, train and aircraft seats are
having to accommodate our ample behinds. In areas where
we can specify our own space we have supersized up. The cars
of today are bloated whales compared to the sleek minnows
of yesteryear. The average automobile on sale in Europe today
weighs around half a tonne more than it did in 1977. Part of
this comprises safety features: airbags, crumple zones and
luxury gadgets of course, but a lot is to do with the sheer
increase in size needed to swallow up our enormous bottoms.
The US car market, after decades of downsizing, has now
reverted to type. More than half of all vehicles being sold
today are trucks – or SUVs – partly because when you weigh a
fifth of a tonne and your teenage daughter weighs more than
Mike Tyson you really do need a truck to carry you around.
Our girth is making us drive bigger cars and is hence contributing
to global warming.
The story of obesity looks, at first glance, to be a simple one.
We are fat because we eat too much and exercise too little.We
have become lazy and indolent. Being so fat, we are putting
why are we all so fat... and does it really matter? 143
our health at terrible risk. Most government-funded experts
warn of an obesity-related health crisis in years to come. And
the solutions are equally simple. Eat less, eat better food and
exercise more.
But there are some big fat problems with this simple thesis.
For a start it is not clear that being fat is necessarily making us
as unhealthy as we have been led to believe. The biology of
obesity is turning out to be more complicated than was once
thought; it may be far more complicated than simply calories
in, calories out. And the solution, if some maverick scientists
are right, may involve rather more than going on a diet.
The obesity epidemic certainly doesn’t – so far – seem to be
doing us as much harm as feared. In August 2006, a study conducted
by the Mayo Clinic in Minnesota was published in The
Lancet. The report was a metastudy – a study of published studies
– and the findings took in results from a total of more than a
quarter of a million patients looking at the link between weight
and health. The statistics were simple and the findings pretty
conclusive, so, unlike many counterintuitive ‘studies’ that make
headlines, this is one that can probably be taken seriously.
The Mayo team found that people who were overweight
and who had already been diagnosed with heart disease had
significantly better survival rates than those classified as ‘normal’.
Even mildly obese people did better than those with the
‘healthiest’ body mass indices (BMIs), the standard catch-all
assessment of weight and health. You actually had to be
severely obese to do less well than someone in the normal
weight band.
While the scientists took some pains to avoid being quoted
as saying ‘being a bit fat is actually pretty healthy’, this was the
unavoidable conclusion. In fact, what the findings highlighted
the most was the probable unreliability of the BMI as a way of
gauging anything useful about one’s health. Dividing your
weight in kilos by your height in metres squared yields a
144 10 questions science can’t answer yet
number which may or may not be as useful as your foot size
when it comes to determining the likelihood of one living to a
ripe and healthy old age.
Many elite athletes fall into the ‘obese’ range. The New Zealand
rugby union player Jonah Lomu is probably one of the fittest
men on the planet, yet he is officially obese, with a BMI of
32. Hollywood stars Brad Pitt and Russell Crowe are overweight
and borderline obese, respectively, despite there being
no evidence that either man is suffering from any obesityrelated
illnesses.
Weight per se may be a poor indicator of health, simply
because heavily muscled individuals are relatively dense (producing
high BMIs), whereas a bulk of fat is of a much lower
density. Many doctors now prefer to use the simple waist measurement,
which apparently correlates far better with predicted
health outcomes. Even in the US, few people are
extremely obese (BMIs of more than 40) so it is perhaps not
surprising that the predicted health and life expectancy crisis
has so far failed to materialize.
Morgan Spurlock, an American journalist, made a hugely
successful movie in 2004 called Supersize Me, in which he lived
on nothing but the products of one fast food firm, McDonald’s,
for several weeks.We were told that as a result this previously
lean, healthy young man put on a lot of weight, became
stressed, lost his sex drive and, most terrifyingly, started to
suffer from incipient liver failure. This film is now cited as
strong evidence that you get fat by eating fast food, and as a
result you will also start to die.
In fact the media have been rather uncritical of Supersize Me.
McDonald’s is of course a global hate figure for many, and it
makes an easy, if not lazy, target. When I spoke to one
extremely eminent liver expert after the film was released, he
voiced extreme surprise concerning the effects that Spurlock’s
diet had apparently had on his liver in such a short time.
why are we all so fat... and does it really matter? 145
In 2006, Spurlock’s experiment was repeated, this time
under controlled laboratory conditions, in Sweden. Fredrik
Nyström from Linköping put 18 volunteers on a ‘supersize’
diet – not just McDonald’s, but consisting of an instruction to
double their daily calorific intake using junk food, and to
avoid physical activity as much as possible (another aspect of
Spurlock’s regime).
The volunteers were poked and prodded throughout, and
a new X-ray technique called DEXA (dual energy X-ray absorptiometry)
was used to measure muscle, fat and bone density
accurately. A barrage of liver tests and blood cholesterol
levels were taken. The works, in short.
The results were extremely interesting. The volunteers, unsurprisingly,
put on weight, but in wildly differing amounts.
One, Adde Karimi, a nursing student, put on just 4.6 kilograms,
and half of that was muscle. And this after a month on
6,600 kilocalories a day and virtually no exercise.
Additionally, his cholesterol levels actually dropped. Another
volunteer put on 15% extra body weight in just two weeks.
‘Some people are just more prone to obesity than others’,
Nyström told New Scientist, which reported the experiment in
January 2007. Interestingly, none of the first batch of volunteers
in the Swedish study suffered the elevated liver enzymes
that caused Spurlock’s doctor to make him quit his experiment,
although some later volunteers did suffer this sign of
liver damage.
The message from this experiment? It really is more complex
than calories in, calories out. And the message that a
high-calorie, fast food diet will inevitably make you ill is probably
incorrect. On identical regimes, some people put on
weight far more easily than others.
It has been clear for some time that the link between diet
and cholesterol levels is tenuous, to say the least. But this
experiment showed that we may have to throw away our pre-
146 10 questions science can’t answer yet
conceptions about this chemical; some of the Swedish volunteers
had reduced cholesterol levels and even increased levels
of ‘good’ high-density lipoprotein. And this is not the only
Spurlockesque experiment performed recently. A batch of
other experiments, some amateur stunts, others more scientific,
appear to show that consuming fast food is not enough
on its own to ruin your health and become fat.
The old fatties’ excuse, ‘It’s my metabolism’, really might
have some credibility after all. The extra calories have to go
somewhere, of course. Nyström suspects that ‘naturally thin’
people, if there are such things, simply burn off the excess
energy as heat. He noticed that his initially thinnest volunteers
complained a lot about being hot and sweaty when on the diet.
Interesting though these results are, it is undoubtedly the
case that obesity must be linked to how much we eat. Fatness
is hugely related to class and income, particularly in the
West. All food has got hugely cheaper since the 1950s, and
cheap food has become, relatively, cheapest of all. So while
the price of high-quality fresh fruit and vegetables, wellreared
meat and fish has fallen, the prices of cheap breads
and cakes, candies and low-quality fast food that requires
little or no preparation have fallen fastest of all. In the 1950s,
when the hamburger chains began their relentless expansion
across the US, a meal in a fast food restaurant cost around a
working man’s hourly wage. There are hamburgers now on
sale in the US for as little as 39 cents, which would take about
three minutes to earn on the minimum wage. Calories have
never been so cheap at any place or time since we gave up
hunter-gathering.
How we get our calories has changed too. If you walk
around an American supermarket you will see nothing but
‘lite’ and ‘lo-fat’ products on the shelves. What you won’t see
is an admission, on much of the packaging, that a lot of this fat
has been replaced (because it needs to be if this stuff is to
why are we all so fat... and does it really matter? 147
remain edible) with something called high-fructose corn
syrup (HFCS), which has replaced good old sucrose as a ubiquitous
ingredient in American processed foods. Corn syrup,
cheap and easy to produce in vast quantities, has been the
subject of much media interest and has been dubbed ‘the
devil’s candy’. It may play a role in the obesity crisis.
Its use in the US dates from the same time – the early 1980s –
that the fat epidemic began to take off. But there is little evidence
that this stuff is to blame. It is hard to explain, for
instance, why eating HFCS should make you fatter than
sucrose. Maybe it is a gloopy red herring.
Another simple factor must be the rise of the automobile.
Gasoline is now cheaper, in real terms, than it has ever been,
certainly in relation to wages. So are cars. It is now quite
affordable for even quite poor people in the richest countries
to drive everywhere, and most do.
Obesity rates in the US are among the highest in the sprawling
cities of the south and southwest, where distances
between homes and basic amenities are such (coupled with a
simple lack of sidewalks and an often harsh climate) that getting
everywhere by car is a necessity. In many of these places
you simply cannot walk to the grocery store even if you want
to. People are thinner in New York City than they are in urban
Texas at least partly because it is impossible to park and mostly
because everyone can and does walk everywhere.
Plus, of course, fast and (in particular) unhealthy-and-fast
food is now the subject of multi-billion dollar marketing campaigns,
often aimed specifically at hooking children into lifelong
habits while they are at their most impressionable.
All in all, we are generally living a more sedentary lifestyle
than ever before. British civilians were probably at their
healthiest during and after the Second World War, when a
combination of austere food rationing and petrol shortages
led to the UK having probably the healthiest diet in its history,
148 10 questions science can’t answer yet
coupled with a mass, involuntary exercise programme involving
long commutes by cycle and on foot.
The generation of Americans raised in the 1940s was in even
finer fettle. Beef- and corn-fed, the strapping youths – farmboys
and factory workers – sent over to Europe to fight the
Germans seemed to the locals like supermen.
A hundred years ago the majority of workers worked with
their hands. Now, muscle power is no longer in demand. It is
hard to believe just how strenuous life was even four or five
generations ago. As well as walking everywhere, keeping
house involved hours of backbreaking drudgery; farm work
was even harder, as the Industrial Revolution spawned countless
millions of jobs in which brawn was far more important
than brain. Nowadays, the growth of the service sector in all
developed countries means that for most people exercise, if
taken at all, has to be deliberately taken.
Millions of people in theWest probably take no effective exercise
at all, save the walk from their car to the office and vice
versa. In the richest (and some of the fattest) countries parental
paranoia has seen a sad generation of children hidden indoors
in front of their computer screens when they should be outside
playing, and driven everywhere, when they should be walking
or cycling to meet their friends or to go to school.
But explaining the obesity epidemic cannot be this simple.
We do indeed eat a little more and exercise a little less than,
say, the generation born in the 1930s, but poor diets and sloth
have not increased markedly since 1980 – when the obesity
epidemic really started to take off. And the fat plague is really a
staggeringly recent phenomenon. It is not even a whole generation
old. According to the US government’s Centers for
Disease Control and Prevention:
... in 1995, obesity prevalence in each of the 50 US states
was less than 20 percent. In 2000, 28 states had obesity
why are we all so fat... and does it really matter? 149
prevalence rates less than 20 percent. In 2005, only 4
states had obesity prevalence rates less than 20 percent,
while 17 states had prevalence rates equal to or greater
than 25 percent, with 3 of those having prevalences equal
to or greater than 30 percent (Louisiana, Mississippi, and
West Virginia).
Car ownership and use in 1970s America was certainly a
little less than today, but not hugely so. Diets may have been
slightly different, but, surprisingly, Americans now consume
less fat and much less meat than they did a generation ago
(although they do consume rather more sugar, especially that
fructose syrup).
While it is mildly challenging to scientific orthodoxy to state
that some people may be able to eat far too much (and even
be very fat) and yet remain healthy, it is utter heresy to suggest
that some people may become obese because of an infectious
agent. And yet the recent idea that you can catch fatness is
proving surprisingly hard to dismiss.
The idea that you can catch obesity seems counterintuitive
and absurd. So did the idea that you could catch stomach
ulcers until Australian pathologist Barry Marshall drank a cocktail
of Helicobacter pylori and won a Nobel Prize for proving that
you could. Infectious agents are now suspected to the cause of
a host of conditions, from schizophrenia to heart disease, that
were once assumed to be the result of environment factors or
genes. In 2001, a team from Johns Hopkins University found
that people with schizophrenia were more likely than the general
population to carry an activated version of a retrovirus
called HERV-Win their DNA. Again, this is not to say that schizophrenia
is an infection, but it may suggest that blaming the disease
purely on genes or upbringing may be too simple.
And obesity? Some doctors, led by a charismatic Bombayan
called Dr Nikhil Dhurandhar who now works at the Penning-
150 10 questions science can’t answer yet
ton Biomedical Research Center in Baton Rouge, Louisiana,
think that infection may be a factor in the fat plague.
Dhurandhar had suspicions about a type of pathogen called
an adenovirus; various strains are responsible for diseases like
colds, diarrhoea and conjunctivitis. Animal experiments carried
out in the early late 1990s and early 2000s showed that
one strain, AD-36, could cause spectacular weight gain in
infected marmoset monkeys. More evidence that viruses may
play at least a part in unexplained obesity came with the finding
that, in blood taken from 313 obese people and 92 lean
people from Wisconsin, Florida and New York State, antibodies
were present in just four of the lean subjects and 32% of
the overweight ones.
To check that it is the virus making people fat, not that it is
being fat that increases one’s susceptibility to infection, he
looked at the prevalence of three related adenoviruses – AD-2,
31 and 37 – and found no difference between the obese and
non-obese populations.
The history of science is littered with spectacular claims that
X causes mysterious Y, usually made by charismatic and
highly-qualified people, that fade into nothing. Often what
sinks such claims is the lack of a plausible mechanism, but Dr
Dhurandhar has an answer. He has discovered that the virus
appears to target the immature precursors to fat cells, altering
their DNA and speeding up these cells’ maturation.
This is not a theory shipwrecked on the wilder shores of
implausibility. Dr Dhurandhar’s work has been published in
numerous peer-reviewed journals, including the International
Journal of Obesity and Obesity Research. ‘When I started out I
guess my credibility rating was zero per cent’, he says. ‘Now it
is maybe 60 or 70’. Most mainstream nutritionists are still
pretty dubious, but some, such as Dr Iain Bloom, a metabolic
medicine specialist at Aberdeen University in the UK, are
cautiously supportive.
why are we all so fat... and does it really matter? 151
So this is still far from the mainstream, but a long way from
being bonkers. Interestingly, another of Dr Dhurandhar’s findings
suggests that adenovirus-triggered obesity may be associated
with increased sensitivity to insulin, in turn suggesting
that people who become overweight may be actually less susceptible
to diabetes than the general population. Depressingly,
if adenoviruses do indeed turn out to be a co-factor
(probably acting in concert with some sort of genetic susceptibility)
to one ‘strain’ of obesity, the chances are that, like any
viral infection, it will turn out to be essentially incurable.
The adenovirus may not be the only micro-organism making
us fat. In December 2006, Nature1 published a report by Jeffrey
Gordon and colleagues from theWashington University School
of Medicine in St Louis, Missouri, showing that the gut flora of a
subset of obese people (and obese mice) differ subtly from the
microbes found in lean individuals. Specifically, the ratios of the
bacterial groups known as Firmicutes and Bacteriodetes were different.
Gordon’s team surmises that the bacteria in the ‘obese’
guts enable their hosts to metabolize calories more efficiently,
leaving fewer nutrients to go to waste in faeces.
It is thus plausible that some sort of symbiotic mechanism
has evolved where ‘friendly’ gut bacteria enable us to get the
most out of every mouthful (a good thing in normal circumstances,
but a bad one where food supplies are unlimited).
It is very early days. It may well turn out that the ‘microbe
that causes obesity’ will disappear along with the Snark. But
there is now quite a lot of evidence that the story of our
expanding waistlines may be a little more complicated than a
simple tale of sloth, greed and increasing prosperity. It is certainly
the case that when everyone starves, none are fat. But it
is also certainly the case that when food is plentiful some
people remain lean, even when they appear to consume a
great deal. Most challenges to scientific orthodoxy turn out to
be diversions.
152 10 questions science can’t answer yet
A few – a very few – do have something to them; maybe the
infection–obesity link is one such. There is certainly a lot that
needs to be explained about why we are all becoming so fat –
the mysterious maintaining of general health levels and life
expectancy, the speed at which the phenomenon has grown
and in particular the interesting microbiological findings
which suggest that as well as diet, exercise and genes, sheer
bad luck may play a role in expanding your waistline. Fat is a
feminist issue. It is also a scientific one, and the science is turning
out to be not as straightforward as we once thought.
Reference
1 Ley, R. E., Turnbaugh, P. J., Klein, S. and Gordon, J. I. (2006)
Microbial ecology: human gut microbes associated with obesity.
Nature, 444, 1022–3.
why are we all so fat... and does it really matter? 153
9
can we really be sure the paranormal
is bunkum?
154
Like most people who consider themselves to be rational
beings, I have a long hate list of tiresome beliefs, notions and
lifestyles which I reckon consign a person to the dark side. This
list includes the following:
all religions, whether organized or utterly chaotic
astrology, spoon-bending and other alleged demonstrations
of psychic powers such as telepathy
any manifestation of the New Age, including talk of chakras,
channelling, crystals and chanting
the ‘wisdom of the East’ and the ‘wisdom of the Ancients’
the healing power of whale music
aromatherapy, rebirthing and reincarnation
alternative medicine, especially homeopathy and really
especially homoeopathy
essential oils
anything Ayurvedic or involving gurus
ghosts, fairies and, far worse, faeries
Collectively all this stuff brings me out in a rash. Indeed, I suspect
that the barstool question ‘What star sign are you?’ is an
excellent Darwinian adaptation hardwired into the mating
strategies of the deluded to provide a signal to sensible folk to
keep clear and protect the gene pool.
In my world view (and in the world view of most people I
know and love who are all, of course, sensible right-thinking
people like me) this is all gibberish, wishful thinking by people
who are not interested in finding out how wonderful the
world really is and who wish instead to replace it with a garish,
Disneyfied version where there are fairies (or faeries) at the
bottom of every garden and a big, kind man in the sky to
watch out for our every move.
I was especially pleased to learn from a psychology professor
once that a belief in things like astrology and mysticism
can we really be sure the paranormal is bunkum? 155
is hugely correlated with a highly conservative right-wing
outlook on life generally. Great, I thought. These kooks are
not only talking gibberish, they are a bunch of Nazis as well.
It’s therefore more than all right to hate them, it is almost a
duty.
Here is another list, this time of things I do believe in:
huge stars which collapse in on their own weight and at
whose centres there are maybe portals to another universe
the possibility that an infinite number of parallel universes
exist, each containing every possible permutation in the
history of time. I believe it is just about possible that out
there, there is not only a universe where Al Gore became
President of the US in 2000, but an unhappier place
where Hitler won the Second World War.
objects like electrons and maybe even whole atoms can
be in two places at once
when you put a stopwatch on an airliner and fly it over the
Atlantic the act of accelerating this object to a few hundred
miles per hour will make it run very slightly slow
the Universe began in a stupendous explosion of space,
matter and perhaps time as well, and we have managed
to find a date, around 13.7 billion years ago, when this
event occurred
the Universe is full of a strange invisible substance which
completely fails to make its presence felt save through its
gravitational attraction to ordinary matter. I am quite prepared
also to believe in an even more mysterious, monstrous
dark force that looks like it might one day rip
everything apart
So what is it that differentiates the first set of beliefs from the
second? What makes the second lot ‘scientific’ and the first lot
156 10 questions science can’t answer yet
‘mumbo jumbo’? Why is belief in homeopathy silly and yet
belief in string theory completely sensible and mainstream?
Why do you get Nobel Prizes for working in one set of these
fields and derision for working in the other?
The answer gets to the heart of what science is. The rejection
of ‘flaky’ beliefs like chakras and homeopathy is not because
these things are intrinsically strange, or even spooky. After all,
quantum physicists have performed experiments which have
shown that two electrons can send ‘messages’ to each other
thousands of times faster than light. Any explanation for this
‘entanglement’ involves hypotheses like sending messages
back in time, which is far, far spookier than homeopathy.
No, science does not reject certain beliefs because they
sound flaky, but because they have been examined by experiment
and found wanting. The scientific method says that you
have an idea, and test whether it is true. Belief – except in the
veracity of this method – does not, or should not, come into it.
And time and time again, when science has tried to verify
things like homeopathy or the existence of telepathy, it has
failed. The ‘proof’, if there is any, for the phenomena on the
first list depends hugely upon anecdote. And anecdotal evidence,
while not always entirely worthless, is generally the
enemy of reason.
But we must be careful here. It is tempting to dismiss a
whole set of beliefs – indeed a whole belief system – purely on
the basis of prejudice rather than on evidence. And it is far too
easy to link one set of beliefs (for which there is no evidence)
with another (for which there might be) simply because they
sound a bit similar and tend to have the same devotees.
People who ‘believe’ in crystal therapies and chakras often
also believe in acupuncture and telepathy. And while there is
zero evidence that the first two are real, there is quite a lot of
evidence that acupuncture ‘works’, and some evidence for
telepathy.
can we really be sure the paranormal is bunkum? 157
Believers in the paranormal often point out that science is
quite prepared to believe in stuff that is not only spooky (like
entanglement) but also stuff for which there is very little
experimental evidence.
They have a point. Take string theory, the idea that at its
heart the Universe is composed of countless tiny vibrating
threads made of, perhaps, space–time. Each is tuned to a different
harmony, creating the electrons, quarks, neutrinos and
so on of which we are made. It is a beautiful theory, and, at
least in its very broadest concepts, quite a simple one, and if
there is one thing that science has taught us it is that the simplest
answer is very often the right one. But is it right?
Mathematically, string theory (I am told) pretty well has all
its ducks in a row. When I met Lisa Randall, the Harvard University
physicist and evangelist for string theory as the best
possible candidate we have for a prototype theory of everything,
she certainly impressed me with her passion. People like
Randall live in a mental world upon which we can only gaze in
awe. Who on earth are we to doubt them?
But some people with far more mental equipment at their
disposal than I do doubt all this. String theory has, so far, absolutely
no observational or experimental evidence to back it up.
Already there is something of an anti-string theory backlash.
The problem with string theory, say the sceptics, is that it is
fundamentally untestable, and that makes it fundamentally
Not Science. Because to expose particles on this scale and
study them we will need to build atom-smashing machines
two or three orders of magnitude more powerful than anything
we have mooted so far.
And the scepticism about the New Weird Science doesn’t
stop there. Parallel universes are an elegant solution to two
large scientific dilemmas: the resolution of quantum events
and the problem of explaining why the Universe seems to be
so finely tuned for life. And yet, like those strings, we have
158 10 questions science can’t answer yet
absolutely no empirical evidence that there are universes out
there where Hitler won the war or where another you is reading
Astrology for Cats right now.
Part of the reason that string theory and, say, homeopathy
have been put in separate boxes is of course the personalities
involved. The people working on string theory, like the people
working on dark matter and the people trying to fathom the
nature and possible cause of the Big Bang are proper scientists,
proper people in fact, clearly highly intelligent and with
years of training behind them.
They submit their findings to respected journals where their
peers mercilessly rip their work to shreds, trying to find fault and
any evidence of error or fraud. Their hunches, hypotheses and
theories are testable and fallible and their experiments repeatable,
and that is what makes them proper scientists, not charlatans.
Some of these people become stars, write best-selling books
and make a great deal of money, but most do not. Some are
impossible egoists every bit as queeny as the worst showbiz
diva. But again, most are not. The majority of top-end scientists
I have met, even Nobel Prize winners, are surprisingly
unassuming people, and perhaps a majority of them find the
fame which may be unwittingly thrust upon them embarrassing
and hard to deal with.
Compare these people with the other lot. They often wear silly
clothes and spout unfathomable gibberish, and their most successful
proponents seem to worship both fame and money a
great deal. Little training is required to set oneself up as an astrologer,
faith healer or spoon-bender, just a ‘gift’, some charm, a
thick skin and a snappy personality. These people often react
very badly when asked to put their findings or qualifications up
for serious scrutiny, and they often reach for their lawyers at the
suggestion that they may be mistaken in their beliefs.
The work of these people is helped greatly by the strange,
modern climate of scepticism, indeed cynicism, of all things
can we really be sure the paranormal is bunkum? 159
scientific, a rejection of ‘modern thinking’ and indeed, implicitly
(although it is never quite put like this) of the whole
Enlightenment project.
Finally, there is the unalterable fact that, historically, much of
even the edgiest science turns out to be right. It sounds as silly
to believe that a pocket watch on an airliner runs slow as it
does to believe that the position of the planet Neptune when
you were born may influence your career and choice of partner,
but the fact is that we can measure the former very accurately
with atomic timepieces, and it does indeed turn out to
be the case that fast-moving clocks runs slow. And it also turns
out that the position of Neptune has, statistically, no influence
at all on the course of your life.
Similarly, the notion of dark matter sounds absurd until you
realize that with some very elaborate and expensive telescopery
and computery, you can actually see the gravitational
shadow of this stuff writ large in the heavens. No one has ever
got a paper in Nature based on their spoon bending powers or
their ability to predict the future.
And yet. There is a danger here that we are creating a false
dichotomy, an unnecessary barrier between the logical and
the absurd that is really a barrier between two different
mindsets than between the real and the unreal. Strange,
impossible, weird and even spooky things are OK as long as
they are ‘scientific’, but not if they are just spooky. Quantum
action at a distance is all right; ghosts are not. Quantum consciousness
is worthy of debate, telepathy is beyond the pale.
NASA employs scientists to ponder the existence of microbes
on Mars, yet to believe seriously in UFOs is to stray well into
nutterdom and certainly will count against you if you are
going for a job with the Agency.
While we can all agree that crystal therapy and channelling
are almost certainly nonsense of the first order, what about
hypnotism and acupuncture? Can we really be so sure that all
160 10 questions science can’t answer yet
this stuff, the stuff of the loonies, the credulous and the fraudulent,
should be thrown away with the mystic and astrological
bathwater?
Do we need to think a bit more carefully about exactly
where we place our Great Wall between the rational and the
absurd and even allow for the fact that sometimes that wall
may need to be given a few gaps?
Fundamentalists would say that giving airtime to any of this
stuff is an abomination. I remember hearing a very distinguished
British thinker saying on the radio a few years ago that
even if it could be shown, beyond all reasonable doubt, that
telepathy was real, he would still want nothing whatsoever to
do with it. Such a discovery, he said, would be trivial and
unimportant. It would tell us little that we didn’t already know
about the brain and the mind, how the world works and how
we fit into it.
Well, I am sorry, but this will not do. As the Nobel Prize-winning
physicist and paranormal sympathist Brian Josephson
says, this is a ‘pathological disbelief... a statement which says
“even if it were true I wouldn’t believe it”’.
It is certainly the case that if it could be shown, for example,
that telepathy works it really would change an awful lot. If we
discovered that brains are able to communicate, through
empty space, directly and without the intermediary of spoken
language, then this alone would tell us a great deal about
human consciousness, the mind, and the transmission of
information. Obviously I have no idea how telepathy works, if
it does (which I doubt), but that is not the point. Maybe it
would involve some sort of quantum spookery, maybe some
sort of electrical field.
According to Richard Wiseman, a British psychologist who
has spent many years studying and commenting upon parapsychology,
the discovery that any of this stuff is real would be
hugely important:
can we really be sure the paranormal is bunkum? 161
It would not be a small change to our scientific model of
the world if astrology, ESP or ghosts were genuine. It
would be a radical shift. That is why these topics make
many scientists instantly say that these things cannot be
true.We must remember that about half the public believe
in these things and so they are deserving of investigation
from that perspective alone.
Science is in the business of testing ideas, torturing them,
wringing every last possible anomaly out and hanging them
to dry. If you prove that something is right, that isn’t good
enough. You have to show everyone else what you have done
and they must repeat your experiments and get the same
results. Only then has knowledge advanced.
Can any of this rigour be applied to the paranormal?Well yes,
actually. Parapsychology is the name given to a group of (so far)
hypothetical phenomena which include extrasensory perception
(ESP), telepathy, clairvoyance, precognition, remote viewing,
telekinesis, psychic healing and morphic fields.
What these phenomena have in common is that they are, at
least in principle, testable. And since the 1890s there have
indeed been concerted efforts made to find out whether these
are real, in controlled conditions, in the lab. Some of these
experiments, where people sit in sealed rooms and try to
transmit images on cards – circles, squares, wavy lines and so
on – to another volunteer in another sealed room, have
become quite famous.
So far the results have been rather muddled. Some individual
studies have shown some sort of statistically significant
effect (i.e. the ‘receivers’ were getting the ‘right’ answer far
more often than would be expected simply by chance), but
the sceptics point out that if you do a ‘study of studies’, if you
look at dozens or hundreds of individual attempts to ‘find psi’
the interesting results disappear in a puff.
162 10 questions science can’t answer yet
It is fair to say that no investigation into telepathy has yet
produced results which have convinced the scientific mainstream
that there is any kind of interesting effect going on
here. The parapsychologists meanwhile maintain that such
metastudies instead reinforce the certainty that something
interesting is going on.
Perhaps the most ‘successful’ of the ESP tests are the
‘Ganzfeld’ experiments, which were first conducted in the
1970s. Volunteer ‘receivers’ are put into a state of near sensory
deprivation, in a soundproof room with translucent spheres
placed over their eyes, bathed in red light and with white
noise played through headphones. The idea is to create a
‘changeless sensory experience’, fully open to any telepathic
signals, should they be there.
There are several variations in the methodology, but basically
the receiver is asked to rank a series of images in terms of
how well they correspond to ‘signals’ sent by a ‘transmitter’ in
a sealed room. According to experimenters, overall Ganzfeld
trials have shown the existence of psi effects beyond all reasonable
doubt – one figure quoted is that you would expect
results such as have been obtained to have occurred by
chance only one in 29 quintillion times.
Since then, however, meta-analyses of Ganzfeld experiments,
by Richard Wiseman and others, have apparently
shown no such effect. There have been allegations of experimental
error and irregularities. Perhaps most importantly, the
assumption that any statistical anomaly must be due to a mysterious
psi effect has been challenged; maybe telepathy is at
work, but maybe there is a hitherto unsuspected error in the
experimental protocol.
Experiments are done, and results argued over, and parapsychology
as a whole goes in and out of fashion. A hundred
years ago it was reasonably respectable, with even Darwin’s
great protégé Alfred Russel Wallace having a thorough
can we really be sure the paranormal is bunkum? 163
dabble. Then, as the 20th century dawned, an extreme, rationalist
mindset took hold and any sort of psi research became
seriously beyond the pale.
And after that, came the ESP experiments and now, finally,
the new scepticism. It is true that several respectable universities
now have departments and research bodies devoted to
parapsychology, but despite this the whole field is still tainted
by its associations with the charlatans and frauds who perpetrated
the spiritualist movements of Victorian times. To some,
this has led to irrational prejudice. Brian Josephson has
accused mainstream journals such as Nature and Science of
effectively censoring any papers on telepathy, telekinesis and
so on. Put it this way: expressing an interest in psi effects won’t
see the research grants flooding in.
Scientists have a natural inclination to distrust ideas that are
outside their canon of knowledge. There is a sense that parapsychology
is partly ‘owned’ by people outside the traditional
field of psychology, for instance. This may explain a remarkable
and enlightening finding that came in 1979, when a
survey of more than a thousand American college professors
found that a majority (55%) of natural scientists, a large
majority (66% of social scientists) and a huge majority (77%)
of arts professors were prepared to accept that ESP was at least
a possibility worth studying. The only group which expressed
extreme scepticism were the psychologists (only 34%), and a
similar number said that ESP was an impossibility, a view taken
by only one in 50 scientists generally.
In a paper published in 1994 in the journal Psychological Bulletin,
entitled ‘Does psi exist? Replicable evidence for an anomalous
process of information transfer’, Daryl Bem and
Charles Honorton had this to say about these figures:
We psychologists are probably more sceptical about psi
for several reasons. First, we believe that extraordinary
164 10 questions science can’t answer yet
claims require extraordinary proof. And although our colleagues
from other disciplines would probably agree with
this dictum, we are more likely to be familiar with the
methodological and statistical requirements for sustaining
such claims, as well as with previous claims that failed
either to meet those requirements or to survive the test of
successful replication. Even for ordinary claims, our conventional
statistical criteria are conservative. The sacred p
= .05 threshold is a constant reminder that it is far more
sinful to assert that an effect exists when it does not (the
Type I error) than to assert that an effect does not exist
when it does (the Type II error).
This amounts to a defence of psychological scepticism.
Richard Wiseman adds:
Psychologists have carried out lots of work showing that
people are often driven by their beliefs when they evaluate
evidence, rather than being more rational. Also, they obviously
carry out work with people, rather than with chemicals,
and so are used to people cheating, not telling the
whole truth and so on. As such, I think they are more
aware than most of how evidence for an effect may be due
to human deception and self-deception.
In other words, psychologists work in a world where people lie
a lot. Physicists do not. This makes physicists a bit more
gullible.
In their paper ‘Biological utilization of quantum nonlocality’,
published in Foundations of Physics in 1991, Brian Josephson
and Fotini Pallikari-Viras cautiously floated the idea of the phenomenon
of quantum entanglement, which Einstein famously
dismissed as ‘spooky action at a distance’ as a possible mechanism
for telepathy.
can we really be sure the paranormal is bunkum? 165
It is no surprise that the known strangenesses of the quantum
world have often been cited as a possible (perhaps the
only possible) explanation for various paranormal effects from
ESP to the phenomenon of consciousness itself. The Oxford
physicist Roger Penrose has suggested that microscopic structures
inside the brain, microtubules (which are in fact found in
all cells), may be able to make use of quantum effects to produce
the non-deterministic effects of self-awareness and free
will, a view dismissed by many of his peers as twaddle.
In brief, Josephson and Pallikari-Viras say that it is not impossible
that the existence of ‘remote influences’ suggested by
quantum theory (where, say, the quantum state of an object
like an electron or photon, say its spin, or polarization, may
correlate over arbitrarily large distances after they have been
split apart) may indicate that the same effect could lie behind
the direct connection of minds (telepathy) and between mind
and matter (telekinesis).
As to an actual mechanism, the authors accept that invoking
quantum effects in a macroscopic structure like the brain is
stretching credulity, but that it is quite plausible that during
the long evolution of life on Earth natural selection has, in
effect’ tamed the quantum world to use its properties for its
own purpose.
A grand interconnectedness between all life-forms is invoked,
a sort of super-Jungian megaconsciousness. Today,
Brian Josephson says the idea that we will have to ‘throw away
science’ if we accept the reality of some psychic phenomena
is:
... a woolly argument, nonsense. Fundamental physics
may have to change a bit to include the mind but it is not
true to say it would all have to go. When new findings
come along in science it is rarely the case that all previous
beliefs have to be overturned.
166 10 questions science can’t answer yet
But the question remains: why should we take this seriously?
After all, what is the difference between telepathy and the
tooth fairy? It may be hard or even impossible to prove that
these phenomena are not real, but what is the point of wasting
time, energy and money investigating things which are
probably marginal at best and very probably no more than a
figment of our collective imaginations?
Well, for a start, even if we never do uncover evidence of
psychic ability, by carrying out experiments into ‘ESP’ we are
quite likely to find out a lot of interesting things about the psychology
of the self and of deception. That alone makes this
work worthwhile.
More fundamentally, parapsychology is a ‘real’ phenomenon
if only in the way that so many people perceive it as so.
Some sort of voiceless communication has been reported by
human societies across all cultures and apparently across all
times in history. Most cultures report instances where individuals
are able to make contact with other individuals instantaneously
and across great distances.
I think the interesting thing about this is that although the
telepathy experience is quite common, it is by no means
universal and when it is reported it seems to be a pretty marginal
effect. In a way, it is more easy to dismiss beliefs such
as the afterlife and the various deities, simply because such
beliefs are so universal (and hence accepted and unquestioned).
Simple psi effects seem to be rare, and have always been
thought of as something rather special and probably quite
dubious. They also seem to be free of political, religious or
emotional overtones. For what it is worth, I do not believe that
telepathy and other related psi effects are real, or at least I do
not believe that I have been shown anything to convince me
that they are real, but I have no reason to believe with any certainty
that they are not.
can we really be sure the paranormal is bunkum? 167
What about the rest of the paranormal? Well, it is possible to
construct a sort of ‘league of looniness’, with the most plausible
bits at the top and the most foam-flecked reaches at the
bottom. At the top I suppose would be what the high priest of
rationalism Richard Dawkins has recently dubbed the ‘perinormal’.
Here we find hypnosis and maybe acupuncture, both
now, following solid clinical trials, largely accepted to be real,
although mysterious, phenomena. Would he include telepathy?
The sneer could be heard down the telephone line. ‘Almost
certainly not’.
Then the aforementioned classic psi phenomena – telepathy,
remote seeing, perhaps telekinesis. Evidence for these
being real is debated and hugely controversial. But compared
to the next lot this is practically Newtonian physics.
Enter stage left here a curious, mostly North American,
phenomenon called Intercessory Prayer (IP). This is faith
healing, an unholy fusion of parapsychology, mysticism and
traditional religion. In IP studies the effect on sick people of
volunteers praying to God for their recovery is measured. (It
never seems to be the case, puzzlingly, that the volunteers
are asked to pray for a worsening in the patients’ condition,
although in the interests of scientific correctness surely this
should be so.)
Several IP studies have been published showing an effect.
For example, in 2001 Leonard Leibovici of the Rabin Medical
Center in Israel had a paper published in the British Medical
Journal in which he claimed that a group of patients with
blood infections did slightly (but statistically significantly
slightly) better than those who were not prayed for. Studies in
the US have ‘shown’ small but significant effects on patients
recovering after heart attacks and surgery.
IP studies are naturally hugely controversial. Why, many scientists
argue, should money – sometimes public money – be
used to fund such a flaky area of research and one so culturally
168 10 questions science can’t answer yet
specific? The idea of IP raises shudders outside the US
Protestant heartland. And a lot of religious people are unhappy
also; the idea that their God would choose to intervene
to help some people and not others simply on the basis of a
medical trial seems to undermine any commonly held views of
an all-loving and just deity.
UFOs come next. Almost, but not entirely, implausible, the
idea that Earth is being visited by alien spacecraft probably
belongs in the same groupthink as IP and the kookier end of
ESP. The arguments for and against UFOs are well worn, and
not worth repeating here, except the one which says that if it
were definitely and provably the case that no alien had ever
visited Earth in a flying saucer (which it never could be) it
would also most definitely be the case that once humanity
had come up with the notion of aliens then flying saucers
would sooner or later be seen.
Homeopathy? Nah. You can do double-blind trials – they
have done double blind trials – and there is no effect (save perhaps
a rather interesting placebo effect).
Reincarnation? What is the point? We are now on the eversteepening
and slippery slope that leads down into the intellectual
dark side. ‘Proper’ religion probably belongs in its own
category, perhaps a rival league, a bit like the two rival codes
in rugby football.
Finally, it seems that a line must be drawn. Not a solid one,
but a broken and permeable barrier between the acceptable
and unacceptable. Richard Dawkins is probably being too
fierce here, but his idea is a good one. Accept, grudgingly and
with a certain amount of kicking and screaming, paranormal
(all right: ‘perinormal’) phenomena into the scientific fold if
and when there is overwhelming evidence that there is something
here worth studying.
The paranormal is, probably, bunkum. Most of it, most of
the time. But around the fringes it is just possible that science
can we really be sure the paranormal is bunkum? 169
is starting to investigate something that is as hugely and
deeply interesting as the wildest phenomena in the new physics
and the new cosmology. If we are prepared to believe in
dark matter, multidimensional hyperspace, dark energy and
naked singularities before breakfast, I don’t think a little telepathy
should be too hard to swallow.
170 10 questions science can’t answer yet
10
what is reality, really?
171
This is not a question about the meaning of life. That is whatever
you decide to make it, and is a topic for discussion in the
bar, not a book about science. Nor is this a purely metaphysical
question, although it covers areas that have traditionally
been the domain of philosophers. Instead, this is a question
about the true nature of the Universe. At its heart is the ultimate,
and for now totally unanswerable, question, why
should there be anything here at all? As the physicist Stephen
Hawking wrote, ‘What is it that breathes fire into the equations?
Why does the Universe go to all the bother of existing?’.
When scientists talk about reality they talk about tangible
things – atoms and molecules, particles and radiation. But of
course this is only the reality. Whether directly, through our
senses, or indirectly, through our machines, we construct a
picture of reality that resides not out in the stars and galaxies
but within our heads.
The old solipsistic chestnut about the world possibly being a
figment of our imagination cannot ever be dismissed out of
hand. Neither, as we shall see, can the idea that the world,
including ourselves, is a figment of someone else’s imagination.
That said, the fact that we have managed to formulate
physical laws which correspond so exactly with what we
observe suggests that while ‘reality’ may be what we perceive,
we are perceiving something that is very concrete indeed.
But there is a lot we don’t know about the ultimate nature of
the Universe. For a start, what is its ultimate cause? Twenty
years ago cosmologists stated flatly that the answer was
simply ‘the Big Bang’ and left it at that, but now scientists are
starting to realize that this is not good enough. What was the
bang exactly? Why did it bang and what happened before?
We do not know if the laws that govern our Universe are
arbitrary, or whether they are they are the only laws that there
could be. Could, for example, the size of the gravitational constant
just as easily have been double or half the value that we
172 10 questions science can’t answer yet
see? Or is it the case that there is a deep, underlying logic
underpinning the laws of physics, like the foundations of a
house, that dictates that there is only one possible way that a
universe, if you are going to have a universe, can organize
itself. And if so, where did these laws come from?
Perhaps the hardest question in physics, and one to which
science has absolutely no answer, is that posed by Hawking;
my understanding is that it can be summarised as:
Is it the case that if there is a set of ultimate laws/logical
propositions that underpin everything, do these laws in
their nature demand not only the existence of the Universe
but of themselves as well?
In other words, is it the case that it is impossible for there to
be nothing? And if not, does the fact that there clearly is not
nothing mean anything?
Finally, we can ask, is what we see really what we think we
see? Humans have, ever since they started thinking about the
world and its nature, come up with a number of outlandish
folk cosmologies. The Earth sitting on the back of a turtle. The
Earth as a disc floating in an infinite sea. The sky as a dome
through which the lights of heaven are visible as the pinpricks
of brilliance we call the stars.
Now we think of the Universe as a vast, 92 billion light year
diameter sphere of expanding space–time driven by a mysterious
dark force field that we do not understand and populated
mostly by a ghostly form of matter that we cannot see
and cannot feel. Is this any less strange than those old folk
cosmologies? And is this the whole picture? Or is ‘our’ Universe
simply a tiny mote on the back of a far vaster, far
grander, appendage?
We do have some answers to these questions. Or at least,
some ideas. The concept of the multiverse, a vast assemblage
what is reality, really? 173
of universes, has become very popular in physics. By assuming
a huge or even infinite number of parallel realities we can
explain some of the oddities of the world we see around us,
most notably the strange way in which the Universe seems to
be so finely tuned so as to allow us to live in it.
But it gets even weirder than that. There are some left-field
but logically quite respectable theories that state that just
about nothing that we believe about reality to be true is in fact
the case. The Universe, in these cosmologies, may be a setup,
a creation not of a god or gods but of machine intelligences
living in a world we could never see or fathom.
A popular solution to the initial cause problem, and indeed
all the questions we have about the nature of the Universe, is
of course God. Across most of the world and certainly for a
vast majority of people the existence of some sort of deity
forms a perfectly acceptable bookend to all chains of inquiry
about themselves and the world in which they live. It is certainly
the case too that even in our so-called secular age many
scientists continue to believe in God.
Most scientists do not, any more, consider God to be a rational
solution to the question of ‘How did the Universe come
into existence?’ Old-fashioned Creationism, and its bowdlerized
cousin, Intelligent Design, is the preserve mostly of Christian
fundamentalists in the US, although there are worrying
signs that it is making something of a comeback in Europe as
well. If the answer is God then we might as well all go home.
So let’s move swiftly on.
Modern cosmology is of course on the case when it comes
to these big questions, but just how far have we come from
the days of flat earths and backs-of-turtles? As to the origin of
the Universe, we now have a rather impressive model, the Big
Bang, which seems to explain a awful lot, for instance the existence
and observed spectrum of the Cosmic Microwave Background
radiation (a dull glow, three degrees above absolute
174 10 questions science can’t answer yet
zero, that permeates the cosmos and is thought to be the
dying embers from the Big Bang itself), the observed expansion
of the Universe and the relative amounts of hydrogen and
helium present.
But the Big Bang model is incomplete and there are many
gaps. One important gap, albeit not with the model itself, is
the general conceptual misunderstanding of the Bang as a
gigantic explosion which threw vast quantities of shrapnel
blasting into space, which later became the stars and galaxies.
It is not entirely clear what happened, to say the least, but it is
clear that the gigantic expansion of the universe that took
place in the first millisecond after the Big Bang was an expansion
of space–time itself, carrying the matter and energy
embedded within it. It is better perhaps to imagine the Big
Bang not as an explosion but more as the blowing up of a balloon.
But there are other, more serious problems, as even the
Bang’s most enthusiastic defenders will concede. For example,
as we peer further away from the Earth we see galaxies as
they were long ago. The light from very furthest objects that
we can see left on its journey to Earth very shortly after the
Bang, which is thought to have taken place 13.7 billion years
ago.
These very distant, very early galaxies are only a few hundred
million years old, as we observe them, and should therefore
be packed with very young, immature stars (our star, the
Sun, is more than 4.6 billion years old). And yet many appear
not to be: some of these very young, very distant galaxies look
like mature galaxies full of ‘old’ stars. Then there is the fact
that some of the stars we observe seem to be ‘older’ than the
Universe itself.
The evidence for this is far from clear-cut and is highly controversial,
but it is worth pointing out just to show that the Big
Bang is not a completely accepted model in the way that evowhat
is reality, really? 175
lution, say, is accepted by biology. Even the fact that what the
Big Bang created is so mysterious is problematic. The fact that
the Universe is totally dominated by dark matter and dark
energy – both utterly mysterious – is, as Dr Bob Nichol, an
observational cosmologist at the University of Portsmouth in
the UK, puts it ‘a mystery and an embarrassment’.
What happened ‘before’ the Big Bang used to be seen as a
pointless question, as it was considered that both space and
time were created during the Big Bang; to talk of a ‘before’,
therefore, is meaningless.
But this view has been challenged, most notably by the
Cambridge theoretician Neil Turok and colleagues, whose
‘ekpyrotic’ or cyclic universe describes a bang that is not a real
bang at all but due to events happening in a higher-dimensional
space. The ekpyrotic model does not contradict the Big
Bang, but sets ‘our’ bang in the context of a much greater
ensemble of events and, crucially, no longer states that it is
meaningless to talk of a precursor to the Big Bang.
The theory, in essence, states that ‘our’ universe ‘floats’ on a
three-dimensional ‘brane’ which moves through higher-dimensional
space. The Big Bang, for which we have so much evidence
today, was an event caused when ‘our’ brane, after a
period of contraction, collided with another, generating a
great deal of matter and radiation.
Learning about the beginning of our Universe is proving to
be expensive. Ordinary telescopes are good at peering back
maybe halfway to the start of time, but even to get this far you
need huge machines and the sort of computerized optics
technology that has only been possible in the past decade or
so. But to go back to the beginning, to peer literally into the
mists of time, requires telescopes that can see in high radio
frequencies in the millimetre range.
High in the Chilean Andes, at a literally breathtaking altitude
of 5400 metres above sea level, the world’s costliest ground-
176 10 questions science can’t answer yet
based telescope is under construction: the Atacama Large
Millimetre Array (ALMA). Work has begun on constructing
around 60 large dishes which, when the array is complete, will
allow astronomers to see right back to the very early days of
star and galaxy formation in the Universe, right back to the
first few hundred million years. The young Universe is still
something of a mystery. We don’t understand, for example,
how dark matter and ordinary matter interacted to form the
earliest galaxies, and how this interaction operated through
time to create the Universe we see around us today.
Insights into the very early Universe will also come from particle
accelerators. As well as searching for dark matter particles,
the collisions that will take place in the Large Hadron
Collider in CERN will generate energies on a level similar to
those seen in the Big Bang. It is an extraordinary thought – in a
tunnel underneath the Franco-Swiss border it is possible to
recreate events which took place nearly 14 billion years ago.
One of the big problems for a non-cosmologist is to work out
exactly what the professionals are describing when they are
talking about the ‘universe’ (and should that word have a capital
‘U’ or not?). Firstly there is the observable universe, which is
the sphere of space surrounding the observer (in our case
Earth) containing all places close enough for us to observe
them. This means that the observable universe must be small
enough to allow a light beam emitted by any object to arrive at
Earth in less time than the (absolutely finite) time allowed since
the Big Bang. This means that the observable universe, or Universe,
while large, is most definitely finite; it has been calculated
to have a radius of about 46.5 billion light years (the ‘edge’ of
the universe is thus about 444,400,000,000,000,000,000,000
kilometres away), giving a volume of 3.4 × 1071 cubic kilometres.
(This figure is not the same as perhaps would be
inferred from the 13.7 billion year age figure; the reason the
observable universe is not 27.4 billion light years across is
what is reality, really? 177
because the warping of space–time allows light to apparently
break its speed limit.) There are perhaps 80–200 billion galaxies
in this sphere, called the Hubble Volume, andmaybe a hundred
billion stars in each, so the total number of stars runs well into
the quadrillions. The Hubble Volume is expanding, by definition,
at a rate of one light year per annum. It is big, impressive
and contains an awful lot of stuff, but compared to everything –
the ‘true’ universe – it is probably a gnat on the back of an elephant.
For a start it is an observable universe centred upon the
Earth. No one believes that the Earth is at the centre of the
Universe any more than they believe that the Earth is at the
centre of the Solar System or that our planet is flat. The term
‘observable universe’ is a useful construct as a way of describing
the maximum space in which things and events may be
causally connected to us. Of course, observers in other parts of
the Universe will each have their own ‘sphere of influence’.
The total number of galaxies even in ‘our’ region of
space–time may be hugely larger than the number we can
theoretically ‘see’ (the world ‘observable’ is theoretical and
does not assume anything about telescope technology now or
in the future). But even that may not be enough.
Just a few years ago the idea that the universe might be
composed of a vast ensemble of unknowable parallel realities
was pure science fiction. Now, some quite sane physicists postulate
that to explain away the awkward fact that our Universe
seems to be finely tuned for not only life, but for our sort of
life, and that this is stupendously improbable, it is probably
best all round if we assume that the Universe we think we live
in is merely a tiny facet on an infinitely grander, huger diamond
of creation altogether. In this multiverse, or megaverse,
anything is possible, everything equally likely, and everything
equally unlikely. The multiverse deals nicely with the so-called
anthropic problem.
178 10 questions science can’t answer yet
There are several variants of the multiverse hypothesis. One,
the many-worlds interpretation of quantum mechanics, supposes
that to resolve the apparent paradoxes of quantum
theory every single possible state following a quantum event
does indeed occur in its own universe. The main rival theory,
the Copenhagen interpretation, states, in essence, that only
one outcome is possible, arising as the ‘wave function’ collapses
into one particular state (for example an electron being
over there, or right here). Both interpretations are to an extent
spooky. The multiverse hypothesis invokes the existence of
billions of parallel realities. The Copenhagen interpretation
seems to give a special role to the observer. Einstein objected
saying, ‘do you really think the Moon isn’t there if you aren’t
looking at it?’.
There are other explanations for the multiverse. The miniverses
may exist in an infinite or near-infinite volume of space,
expanded to a preposterous degree by the cosmic inflation
that took place since the Big Bang. In this multiverse, the
brute-force multiverse, all possible outcomes are covered by
the infinite nature of objects, including an infinite number of
duplications (in this multiverse there is an identical copy of
you, sitting reading an identical copy of this book in an identical
room/bus/plane etc. It lies, on average,101029 metres away.
Then there is the multiverse proposed by the Russian-American
cosmologist Andrei Linde, who has proposed a gargantuan
ensemble of universes, each formed by an expanding
bubble of space–time budding off from the others. In Linde’s
cosmology, our ‘big’ bang was just one of an infinite number
of little bangs. Finally, individual elements of the multiverse
may exist as computer simulations (see the argument below)
or of course the multiverse may exist as a combination of two
or more of the above.
The multiverse is by no means universally popular. As Bob
Nichol says, it gives the impression that scientists have ‘given
what is reality, really? 179
up trying to find a theory of everything and simply put the
details of our universe down to the shake of a dice’. At the
most basic level, the many-worlds interpretation of quantum
mechanics appears to violate Occam’s razor; never mind
not multiplying entities needlessly, this multiplies everything
and multiplies it infinitely. But if parallel universes are unsettling,
there is an idea doing the rounds which is positively
disturbing.
Nick Bostrom is a philosopher at Oxford University and his
simulation argument has become quite famous among scientists,
philosophers and lay people alike, partly because of
its unsettling weirdness, partly because of the fact that it
bears an uncanny resemblance to the plot of the popular scifi
film The Matrix and mostly perhaps because although it
sounds crazy, it has so far proved impossible to wholly dismiss
out of hand.
The simulation argument goes like this. First of all, we need
to make an assumption, namely that one day it will be possible
to simulate consciousness inside a computer. If this assumption
is incorrect, if consciousness turns out to be something
impossible to simulate, then the simulation argument fails
immediately. But if it does indeed turn out to be possible to
simulate a thinking self-aware mind in a machine, we can then
go on to make some more, lesser, assumptions.
First of all, we can assume that one day this will indeed be
done. Bostrom points out that computer power is roughly doubling
every 18 months or so. In a few decades or less it should be
possible, at least in theory, to build machines with a processing
power equivalent to that of the human brain. And we must
assume that this will indeed be done. The simulation argument
then goes on to suppose that programmers will indeed use some
of this processing power to create artificial consciousnesses
inside their machines, artificial universes in which they can ‘live’
and furthermore that they will do this more than once (the effect
180 10 questions science can’t answer yet
beingmultiplied greatly by the fact thatmany of these simulated
beings will run simulations themselves).
Again, this seems at least plausible, as even today there are
many instances of computers being used to simulate all sorts
of real-world scenarios, from the complex weather systems
modelled by forecasters to the massive, multiplayer online
games in which avatars and computer-generated ‘characters’
populate imaginary software worlds.
As I write, a story has appeared in the press about the city of
Porcupine. In Porcupine, it seems, there have been street protests
concerning the establishment in the city of new offices
run by the far-right French political party, the Front National.
The protests escalated, in early 2007, to the point where anti-
Nazi activists clashed with right-wing thugs. This is all just
mildly interesting until you realize that Porcupine is not a real
place, but part of a simulated world, an online virtual universe
called Second Life. Online worlds are not new – I seem to
remember a couple around from the mid-1990s, but they
were slow and clunky and horrible to use and no one knew or
cared about them outside the world of the hardline geek.
Second Life might just be different. The software is impressive,
creating a colourful, even elegant world of vivid scenery.
Second Life has, its makers claim, more than 2.4 million users.
And, most importantly, it is becoming more than a computer
game. The Second World uses its own currency, Linden Dollars,
which can be exchanged for real US greenbacks. At the
moment, the only intelligence in Second Life is that of those
two and a half million users – that plus some clever software.
But it can be safely assumed that this is very much work in
progress. Just as scenery can be simulated, so can the ‘personalities’
of the avatars and other beings with which you, the
user, will come into contact. At the moment, and it is worth
stating this over and over again, we have no idea whether
anyone will ever be able to build any kind of conscious awarewhat
is reality, really? 181
ness into a computer program. But let’s just assume we can,
and furthermore that platforms like Second Life will one day
become homes for large numbers of these artificial minds.
Computers will then be simulating consciousness millions, billions,
trillions of times, on millions of machines.
There are no time limits on any of this by the way. These
conscious simulations could be built in the 2020s, in the thirtieth
century or millions of years hence. It doesn’t really matter.
And it doesn’t matter whether it is we humans doing this, or
space aliens living on another planet or even beings living in
another parallel universe. All we need to assume is that at
some point in the entire history of the Universe, or all the universes,
computerized simulations of conscious life are created.
And now, the crux. Because we have assumed that these
computerized avatars have been created over and over again,
it is overwhelmingly likely, by the sheer and simple weight of
statistical probability, that we are living in one of these simulated
worlds, a future (and rather more impressive) Second
Life, possibly sitting in some adolescent’s bedroom, rather
than in the one ‘real’ universe. (Of course, it is just possible
that our world is the real and original world, but just very, very
unlikely.) What then?
Well, everything we think about reality would be wrong.
Our Universe, and us within it, would be a fake. Life would be,
in effect, a gigantic computer game. Our world would be like
a supercharged version of the world of Doom or Grand Theft
Auto, albeit rather more violent. We as individuals would, in a
real sense, be reduced to being no more than the playthings
of imperfect gods – gods who in our case may well be labouring
under the delusion that they themselves are the real
McCoy.
It is a profoundly depressing scenario. Is it testable?Well, it is
possible to test some of the counter-arguments. One is that is
would be impossible to be conscious and not aware that one’s
182 10 questions science can’t answer yet
situation was not real. This is clearly not the case, because it is
possible to dream. When we are dreaming we are in a state of
altered consciousness and do not usually know we are dreaming.
It is certainly possible to dream while thinking that we are
awake. It is also possible to ingest, inhale or inject certain
chemicals which have a profound affect on your perception of
reality. Being conscious is no guarantee of a grip on what is
real.
Mathematically, I am told that the simulation argument
stacks up – provided the assumptions it makes about computer
technology are correct. Bostrom himself does not
assume that computers will be able to be conscious; his argument
is merely predicated on what would happen if they
could, which seems at least plausible. He also allows for the
possibilities that no civilization has ever survived the transition
to technological maturity, or that no civilization will ever
develop an interest in creating a simulated reality.
There are other possible ways to test the argument. Presumably
it would be quite hard to make a simulated universe
that was completely perfect and consistent in all its parameters
– harder at least than making one with a few bricks missing,
a few holes around the edges. Do we live in such a
universe? Well, as it happens there are some rather big bricks
missing in our best models of the Universe. It has so far
proved impossible, for example, to reconcile quantum physics
and relativity.
?
We cannot see these parallel universes (although it is not
impossible to imagine that one day we may be able to build
what is reality, really? 183
machines to detect them). And we have no evidence, save
some mathematical trickery, that we live in a simulated world.
The problem with thinking about alternative realities is a paucity
of evidence.
Slightly less disquieting perhaps than the idea that we are all
the figment of some machine’s imagination is the possibility
that the fundamental basis of reality is information. John
Archibald Wheeler, a quantum physicist, has written that
‘what we call reality arises in the last analysis from the posing
of yes–no questions’. Can we think of the Universe as a huge
cosmic computer, with the ultimate, most fundamental particle
being not the quark or the string but the bit of information?
After all, everything we know about the Universe is
distilled from observation and theory, and that means information.
?
Andrew Liddle, a British physicist, is one of the world’s leading
cosmological thinkers. He says ‘big’ questions can be divided
into three categories. Firstly, in Category A, are those about
which no one has the slightest idea what the answer is, nor
how to go about finding one. Category B comprises those
questions about which ‘there are some theoretical ideas about
which the answer might be, but no observational evidence or
realistic hope of obtaining any such evidence’. And, finally,
Category C: ‘there are some ideas about what the answer
might be, and some hope of finding observational evidence
for or against any given ideas’.
‘One answer to the question of existence’, Liddle says, ‘is the
anthropic principle’. In essence the anthropic principle states
184 10 questions science can’t answer yet
that things have to be the way they are because if they were
not we would not be around to observe them and to ask questions
about them. ‘The fact that we are here to ask questions
and make observations necessarily implies that things have to
exist. In this view, it would have been perfectly possible for
nothing to have existed, but it is simply impossible for anyone
to be able to ask the question unless things do indeed exist’.
Most of the ‘big questions’ of cosmology and reality,
whether or not they stray into the realm of metaphysics, can
be put into one of Liddle’s three categories. Take the possible
arbitrariness of the laws of physics, one of the biggest problems
for science. Do the laws of physics have to be as they are?
‘It is now widely believed that there is some arbitrariness to
the laws of nature we observe’, Liddle says. ‘For example,
there is no reason why gravity isn’t quite as strong as it is.’ Part
of this arbitrariness may come about because the laws of physics
may not be immutable and universal. The gravitational
constant may have been different billions of years ago from
the value it is today, for example. Our visible universe is limited
in size to the distance light has been able to travel since the Big
Bang.
Some cosmologists believe that the physical laws vary in the
very large-scale Universe. At a distance of a googol light years
away, for instance (far beyond our observable horizon), the
speed of light may be different. Or elementary particles might
have different properties. The current front runners in the field
of candidates for ‘theory of everything’ are string theory and
its updated cousin M-Theory. In some interpretations of string
theory it is predicted that the physical laws will be different in
different places in space and time. But the laws may not be
enough. Scratch deeper into reality and we are forced to confront
the question of what it is that underpins the laws.
Indeed, is there a deep underlying logic there at all? One
possibility is that we are mistaken in supposing that there is
what is reality, really? 185
order and not chaos at the bottom of it all. Humans seem to
have an inbuilt need to impose mathematical order, symmetry
and cause-and-effect relationships on a natural world that
often may not work in that way at all. The question of underlying
logic probably falls somewhere between Andrew Liddle’s
categories B and C. Superstring theory is considered quite a
good candidate for an ultimate theory of everything, from
which all physical laws can be derived. It may thus be considered
to be the ‘underlying logic’ for all these laws.
We are really not much closer to answering the question of
why there is anything there at all than were the Ancient
Greeks. The question still falls, as Andrew Liddle says, firmly
into Category A – ‘no idea at all, and no idea how to go about
finding an answer’.
The grand swoop of lights we see on a clear night sky is
impressive enough; knowing that all those twinkling lights are
not only a mere tiny fraction of all the stars out there but in
addition that all the stars together possibly form just a small
part of what is, is humbling beyond belief. The question of
reality and what it is has been asked by philosophers and theologians
for centuries. Now the baton has passed to science. It
remains to be seen whether experiment and observation will
end up enlightening us any more than the elegant reasoning
of old.