The Symbiotic
Planet: A New Look at Evolution
By Lynn Margulis, Weidenfeld & Nicolson,
146pp
Science is about compression. It's the informed
art of squeezing what's knowable about a topic into the neatest possible
package. Intensity is a virtue for science just as for art (or religion). But
you can go badly wrong with a goal like that, squeezing the juice out, leaving
only a husk. Science and technology can reach too eagerly for absolute
explanations and power over nature, can miss or crush complexity.
Understandably, one response is a kind of born-again mysticism, painting
us not as masters of nature but as her custodians or even worshipful children.
The name increasingly given to this portrait of the world as vulnerable mother,
under assault by her rash offspring, is Gaia (pronounced `Guy-uh', after the
Greek Earth goddess).
According to Gaia's devotees, our planet is no mere jumble of animals,
vegetables and minerals. It's a profound but fragile harmony, a system of living
systems that our wildly growing technologies place at risk. Earth is no mere
ball of rock and air infested with evolving life-forms--she is a single great
organism, the largest of all endangered species.
The mutual partnership of diverse living creatures, from bacteria and
fungi to the finned, furred and feathered, is called symbiosis. The mother of
the Gaia theory, Amherst distinguished professor of geosciences Lynn Margulis,
argues that life is better understood symbiotically, co-operatively, rather than
as a red-in-tooth-and-claw Darwinian contest.
In her view, we are all symbionts, creatures linked in vast re-cycling
circuits of matter and energy. In turn, we contain multitudes of symbionts, from
the tiny bacteria that live in our gut and help us digest food to the even
smaller remnant organisms that power our very cells. These mitochondria were
once free-living microbes that long ago entered a pact with larger cells, and
now dwell inside the enormous multi-cellular animals that roam the world and
sometimes dream up science and art.
Does this mean Margulis is a kind of New Age sage, a mother figure for
Gaia-worshipers? Far from it. In her charming new Science Masters book, she is
justifiably irascible at the way her deep idea has been pilfered and misused.
`The co-optation of Gaia-theory by science-haters and media-mongers is
striking,' she says. `Gaia is neither vicious nor nurturing in relation to
humanity; it is a convenient name for an Earthwide phenomenon: temperature,
acidity/alkalinity, and gas composition regulation.' But that's not as dull as
it sounds.
For billions of years, the changing ecologies of life have nudged our
world into a global ecosystem, Gaia, that subtly stabilises the amount of
oxygen, methane and other gases in the air, and regulates the greenhouse effect.
Without the feedback flows summarised in that name, Earth would be cold and
inhospitable. This immense process is brainless as a thermostat, but persists
through catastrophes which wipe out most of its constituent species.
So are we Gaia's chosen children? Not in the running, says Margulis. `We
cannot put an end to nature; we can only pose a threat to ourselves.' The
mindless systems of balance we call Gaia will expunge us, she says, if we try to
grow without limit.
Her argument is elegant and audacious (despite careless proof-reading),
and the telling wonderfully personal. We hear about the passionate, abrasive
time she had as Carl Sagan's young wife, and the scorn from narrow pedants that
greeted her startling grand theory. Nowadays, when it is taught in high-schools,
`I find, to my dismay if not to my surprise, that the exposition is dogmatic,
misleading, not logically argued, and often frankly incorrect.' It's worth
getting the real story from the mouth of Gaia's mother.
By Julian Barbour, Weidenfeld & Nicolson
Time: A Traveler's Guide
By Clifford A. Pickover, Oxford University Press
Surfing Through Hyperspace
By Clifford A. Pickover, Oxford University Press
Even since Einstein, physics depicts reality as
a four-dimensional skein of events located in a warped blend of space and time.
Under some extreme conditions, voyagers might follow a bent spacetime path and
arrive before they left. The universe probably has six or seven extra
dimensions, most of them rolled up out of sight in hyperspace. From a higher
vantage point, perhaps you could see past, present and future in one great
rolling perspective.
That's a chilling notion, at the core of many religious and mystical
doctrines. If we can glimpse the future, our destiny is written in advance. Most
of us recoil from predestination. Doesn't science itself spare us an inescapable
fate? While every event is the inevitable outcome of what's elapsed to date,
chaos saves us from unendurable karma. Small changes in the here-and-now can
amplify themselves into wildly variant futures.
Frankly, that's no comfort to me--I want to be able to choose my
fate, not have it hang on some damn butterfly's wing flapping. Time and freedom
need a better explanation.
Such ideas are explored playfully by Cliff Pickover, who simplifies the
difficult science without turning it to kindergarten mush. Beginners might take
fright at his hands-on approach, since he's not afraid to use equations and
graphs. Don't be alarmed. These simple tools deal with the parts of reality
other methods don't reach, and are quite easy to master.
More formidable, and perhaps of profound consequence to our growing grasp
of the weird universe we inhabit, is Julian Barbour's challenging denial of time
itself. In some ways, his dramatically fresh way of analyzing the world recovers
Einstein's original insight--and perhaps that mysticism Aldous Huxley dubbed
`the perennial philosophy'.
For relativity, the world is like a vast block of glass stretching from
the creation to the voids of futurity. Each moment of time is a section cut
through the block at one angle or another, depending on our velocity. Events are
strung together into `world-lines' that score the glass. In Kurt Vonnegut's
whimsical fiction, alien Tralfamadorians are directly conscious of this `block
universe'. To them, humans are worms 70 or 80 years long, chubby legs at one end
and old withered limbs at the other. Dr Barbour's confronting story is more
astounding still.
If Barbour is right, the universal landscape is best described as
Platonia, named for Greek philosopher Plato's timeless realm of Forms. Platonia
is a complete collection of `snapshots' of possible universes, arrangements of
all the things in the universe at a single instant. The simplest state is Alpha,
perhaps corresponding to the Big Bang. More complex arrangements pile up in a
heap, and paths can be drawn through those most compatible with each other, in a
sequence of `best matches', like a jigsaw puzzle. Quantum theory tells us which
instants are most probable. The likeliest path through those instants is, in
some sense, our history.
Then where does our sense of onward-rolling time, of cause and effect,
emerge? It is a very great puzzle, and one that independent scholar Barbour
struggles to resolve. He conveys the mystery, and even the bones of his
paradoxical answer, with charm and lucidity. Each instant contains a sort of
fossil record of its neighbour, creating an illusion of time's passage. I don't
believe it for a moment, but it's a mind-boggling notion.
A key element of timeless history is a mathematical mechanism Barbour
dubs a `distinguished simplifier', in this case the minimal separation between
two events. He is himself a distinguished simplifier. We're lucky that thinkers
of his calibre bring us work from the cutting edge. His latest thinking is even
available at www.julianbarbour.com, where you can sample his extraordinary
conjectures... ahead of time.
HOW NATURE WORKS:
The Science of Self-Organized Criticality
by Per Bak
Oxford University Press, 212pp
HOW THE MIND WORKS
by Steven Pinker
Allen Lane, 660pp
In the 1980s, `chaos' was science's sexy topic,
although people kept misunderstanding it. Chaos dynamics found that the world's
rich and unpredictable confusion hid simple rules. By the early 1990s, the buzz
word became `complexity'. Interesting things (life especially) exist mostly on a
boundary between frozen order and hissing chaos. Now there's a new spin: the
spontaneous emergence of those complicated and lovely things is due to `self-organised
criticality'.
Criticality occurs when all the parts of a system impact on each other
holistically. Its emblem is a pile of rice. Trickle long-grain rice steadily
onto a flat surface and it builds into a cone, shedding as many specks as it
gains--but in jolts and avalanches, small and large.
Despite Per Bak's enthusiasm, his beguiling book should be titled `Some
of the Ways Nature Works Some of the Time'. Still, in its brief account,
he offers a startling new unified picture of many wildly different phenomena:
word use frequencies, the size and number of earthquakes, the surprising
computer program called the `Game of Life', dinosaur and other extinctions, the
limits of planned economies, and why we will never get rid of traffic jams. Oh
yes, and he thinks he's learned how the brain works.
It's all due to those avalanches. For Bak, a frequent visitor to the
Sante Fe Institute, home of complexity studies, the secret of life is a
mathematical peculiarity called 1/f (`one-over-f') noise. Unlike chaos,
which has a boring `white noise' signal, this key regime creates a weirdly
universal pattern. Mapping it, you get a tall spike on one side, tailing off
quickly as the curve moves to the right. Consider urban scales: for every
megalopolis of ten million inhabitants, there are roughly 10 cities with a
million, 100 with 100,000, and a thousand towns with only 10,000.
It's the same with earthquakes, as measured by the Gutenberg-Richter law.
Most are barely detectable. Some shake villages. Very few are dangerous
monsters. Snow avalanches follow much the same pattern. Graph such frequencies
on a logarithmic chart and you get a straight line, representing a neat
equation. This is Bak's key to how nature works, and you'll need to read his
little book with some attention to see why he might be at least partly right.
Does it matter if he is? Indeed it does. Systems poised at self-organising
criticality (SOC) are neither too hot nor too cold, bubbling with novelty. Every
now and then, an awful avalanche is triggered by some tiny event that can't be
identified in advance. It doesn't take a killer asteroid from space, Bak claims,
to wipe out the dinosaurs. SOC gives us eco-catastrophe for free, the downside
of complexity. Sante Fe's Stuart Kauffman says of such ideas: `I have a feeling
that all this shit links together in some wonderful way.' Couldn't put it better
myself.
Or does it link together just because the human mind is a gadget designed
by natural selection to extract (and impose) patterns or features on the
confusion of the world? Yes and no, according to Steven Pinker's superb new
book. Three times as stout as Bak's, a paperback well worth its thirty dollars,
Pinker's romp through cognitive science's current portrait of the mind covers an
immense amount of territory. It's terrifyingly up to date--900-odd apposite
references take up 37 pages. Luckily Pinker wears his learning lightly and with
appealing whimsy.
"I want to convince you," he says at the outset, "that our
minds are not animated by some godly vapour or single wonder principle."
Rather, mind is a complex package of small dedicated specialists, "and thus
is packed with high-tech systems each contrived to overcome its own
obstacles". The mind, Pinker argues, is what the brain does. Even if
complexity theorists like Bak are right, even if mind emerges only in certain
self-organising regimes of criticality, the way it arises is heavily influenced
by the solutions history has imposed on its evolving development. We are each
parliaments or coalitions of small neural experts.
The ancients suggested that inside each human was a homunculus, a `little
man' who watched, as it were, from behind the eyes. That idea hindered science
and philosophy for ages, and was eventually hustled out of both biology and
literary theory. Now the homunculus has returned, although in a new guise. The
brain is built of numerous agents, some of them genetically hardwired, each with
limited but focussed powers, compiled together into characteristic modes of
sensing, feeling and reasoning--into faculties, another discarded term
making a comeback.
Forcing this reappraisal are many quite recent experiments, using
astounding new technologies to peer inside the working parts of humans and less
complex animals. Pinker leads his charmed reader through a series of exemplary
case histories in `reverse-engineering'. We know what vision does, for example,
and what parts of the brain and optic tract are involved--but to understand the
entire impossible process it's necessary to probe backwards, using evolutionary
insights as a guide.
A central chapter picks apart what's going on when you gaze at one of
those weird computer-generated pictures made up of squiggly lines. Let your eyes
defocus, and an elephant or T. Rex pops out in three dimensions. As it happens I
don't have the neural machinery to perform this useful trick, because my brain
wasn't wired up correctly in infancy. Hence, like a few percent of the
population, both stereograms and reality are quite flat to me (although luckily
I can use other cues to stop myself running into the back of the car ahead).
Pinker's story takes some small effort to follow, but I recommend the trip,
because it's a delightful exploration of... well, of how minds work. Angry
minds, family minds, coarse, subtle and artificial minds. Plus, in the final
chapter, the meaning of life.
On the other hand, don't expect more than is reasonable. Pinker states
candidly at the start: "we don't understand how the mind works--not nearly
as well as we understand how the body works". Even so, "dozens of
mysteries of the mind, from mental images to romantic love, have recently been
upgraded to problems" rather than impenetrable mysteries. But what about
the teachings and verities of the past? "Our old ideas," he observes
stingingly, "were too vapid to be wrong."
Pinker's enjoyable treasure-trove, perhaps even better than his excellent
The Language Instinct, meets the goal he set: "to get you to step
outside your own mind for a moment and see your thoughts and feelings as
magnificent contrivances of the natural world". If you're looking for a
summer book to expand and explain your mind at the same time, this is it.