ONCE you really could judge a book by its cover: serious books didn鈥檛 have
them. Now all you need to read is the cover: a potted biography, a well-written
blurb and all the great ideas in science are yours in a few minutes. A few ideas
are worth more. Here are four books from 1998 that stand out on the shelves of
popular science.
First on the list is John Holland鈥檚 Emergence about the phenomenon
of 鈥渕uch coming from little鈥�. Holland now takes this to the masses.
Just how can a few dumb ants build a bridge over a chasm, he asks, or a
scatter of artificial neurons tell the difference between Ford and Chrysler
cars? Our amazement at this phenomenon has made it appear inexplicable, beyond
the reach of science.
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Not so, says Holland from the University of Michigan, Ann Arbor. And he鈥檚
trying to model it on a computer, reducing emergent systems to a collection of
mathematical mechanisms. He shows it is possible to build structures that behave
like neural networks, cellular automata and other systems that display emergent
behaviour.
At present, says Holland, his work is no more than intelligent probing:
shuffling back and forth between reality and computer models to see how closely
they correspond. But he hopes the mechanisms will let him make predictions about
emergent systems that can be tested.
There seem in Holland鈥檚 eyes to be no limits to his work. But, for your
second helping of brain food, try John Barrow鈥檚 Impossibility. Barrow
makes an excellent case that reaching a limit in science is in itself profound.
It signifies that you are working in a mature field. Barrow points out that we
should see the riches that these boundaries reveal; they are the jumping off
points for new discoveries. His model is Kurt G枚del who proved that there
are mathematical problems we cannot solve鈥攁nd a rich field of inquiry
emerged.
Barrow concentrates on the physical and mathematical side of life, Holland鈥檚
emergence theories are rooted in the maths, but his eventual aim is to bring his
models to bear on the biology. Sandra Steingraber, our third course, needs these
rigorous models to convince people of her argument against pollution鈥攆or a
simple interaction such as spraying a crop with pesticide can lead years later
to a complex degradation of land, water and human health. In Living
Downstream, she makes an extraordinary and passionate appeal for our
attention.
Her case that this is different, however, is difficult to counter. She points
out that this generation has pollution bone deep: we drank PCBs with our
mothers鈥� milk, each spoon of baby food came with a tiny dash of pesticide
residue. Cancer rates are rising. Her title comes from a simple story: people
living beside a river find bodies floating past. They become more and more
skilful at fishing people out, reviving those they could. One huge gap: they
never went upstream to find out who pushed people in.
Our behaviour in face of such disaster is inexplicable. Faced with
well-documented poisoning of land, groundwater tables and ourselves with harmful
pesticides and toxic wastes, we develop elegant operations for the cancerous
tumours they cause, finer ways to measure toxins, endless research into subtle
effects. The one thing we haven鈥檛 done is head upstream and stop the
killers.
Perhaps this is because we are accustomed to slicing up life: this is
ecology, that is chemistry, there is biology. We need, says Edward Wilson, a way
of uniting all sciences. The rewards will be as great as those of the physicists
when Einstein and others united their fields of inquiry. His notion is given
elegant expression in Consilience, itself a lovely, but puzzling word.
It means a springing of knowledge through its relatedness, a jumping together of
things. Wilson asks 鈥淐an we devise a universal litmus test for scientific
statements and with it eventually attain the grail of objective truth?鈥�
Heretical stuff, but he says it鈥檚 achievable. We鈥檙e going to find a few laws
that will unite all science. Here, we complete the turning circle of knowledge:
clearly, Holland should be talking to Wilson.
First reviewed: Emergence, see 鈥淢astering the game鈥�, 26 September, p
38, Review, 25 April, p 45; Impossibility, Review 13 June; Living
Downstream (Addison Wesley, 1998), Review 2 May, p 44; and
Consilience (Knopf), Review 22 August, p42