Never ending story
The tricky thing about writing science books is that the plot keeps on changing. Tim Radford reports on the shortlist for this year's £10,000 Aventis prize
Thursday June 19, 2003

The Guardian

Science books are the last word in non-fiction, or at least the latest. Science writers may go wherever reality extends, across a universe of 13bn light years containing 200bn galaxies, each containing 200bn stars; from the first quantum tick of time's clock 13bn years ago to some proposed slow but never-ending death as, one by one, the stars go out and the void of space expands forever.

Within this ever-open history and untrammelled geography, all questions are legitimate. The answers however are likely to be provisional. This is science, moving toward certainty but never getting there.

In their different ways, the six shortlisted contenders for the £10,000 Aventis science book prize - the winner is to be announced next Wednesday - make exactly this point: science is mostly a story-so-far, a progress report.

Where is Everybody? confronts the paradox of a universe containing only one known intelligent life-form. On the basis of the experience of just one little Goldilocks planet orbiting a run-of-the-mill star in a not-very-special galaxy, the universe ought to be teeming with intelligent life, much of it far more advanced than the one that thought up book prizes as a form of blood sport. But no convincing sign of alien intelligence has ever been detected. This is known to physicists as Fermi's paradox.

Stephen Webb, an Open University scientist, has collected 50 possible answers to Fermi's paradox: they haven't called yet; they have called but we haven't tuned in to their wavelength and (endearingly) they are too busy playing virtual reality games to bother about us. He seems to prefer the melancholy idea that earthlings really are the one successful throw of evolution's dice, the only creatures so far to have evolved minds that may frame such questions.

Steven Pinker, a neuroscientist at the Massachusetts Institute of Technology, has been shortlisted twice before, for his 1995 book The Language Instinct and his 1999 study How the Mind Works. The Blank Slate confronts one puzzle of human nature: what do we think human nature is?

"Every man, wherever he goes," wrote Bertrand Russell, "is encompassed by a cloud of comforting convictions, which move with him like flies on a summer's day." Pinker dissects the idea of the human mind as a tabula rasa, the blank slate, on which experience and ideology write their lessons from politics, history, anthropology and literature. He also chroni cles the terrible misuse of biology by the monsters of the 20th century, from Hitler to Pol Pot.

Pinker says that US public health officials were slow to acknowledge smoking was linked with cancer precisely because the pre-war Nazis had declared war on tobacco: a presumption of innocence, so to speak, by guilty association. But this link was based on probability.

In Reckoning with Risk , Gerd Gigerenzer, director of a Max Planck Institute in Berlin, quotes HG Wells as saying that "statistical thinking will one day be as necessary for efficient citizenship as the ability to read and write". Dream on: a recent survey of 1,000 Germans found that one-third thought that 40% meant either a quarter, or every 40th person.

This international lack of enthusiasm for numeracy explains why the Tobacco Institute, founded in 1958 by US cigarette manufacturers, was able to claim that the link between cancer and cigarettes was "merely statistical" and therefore the question was still open. Washington now has 1,700 such lobby groups, including an asbestos information association to protect citizens from "fibre phobia".

"Only connect," said EM Forster, but the lesson of Mark Buchanan's Small World is that you already have. Mathematicians boast of their Erdos number - their closeness to or distance from Paul Erdos, who co-authored 1,500 papers - and actors play a game called six degrees of Kevin Bacon. If the planet's six billion people were linked randomly, each person would need only 24 acquaintances to connect with every other person in the planet through six degrees of separation. Think of that, next time you start a conversation with a complete stranger in an improbable place and immediately discover a mutual acquaintance. The internet was there all the time: it was just waiting for the mouse, the keyboard and the transistor.

Chris McManus of University College London had so many footnotes to his book Right Hand, Left Hand that he had to consign some of them to the web (http://www.righthandlefthand.com/). Asymmetry is a feature of physics, chemistry, biology and human history: the odd thing is that many of us fail to notice. The structure of DNA is a right-handed helix: a text book by James Watson, the co-discoverer of the structure, had six illustrations in which the helix had a left-handed spiral. "Perhaps it is not a coincidence that Watson is left-handed," McManus points out.

He also points out that a famous portrait of Goethe shows a left foot attached to a right leg, and Russian Imperial Army drill instructors used to attach straw to the right ankle of a recruit, hay to the left and then shout "Straw, hay, straw, hay, straw!"

In The Extragavant Universe , Robert Kirshner, an astronomer at Harvard, puts human life into perspective: one human breath is to one lifetime as one lifetime is to the age of the universe. And according to a relatively recent cosmological wheeze the whole thing took shape in far less than an intake of human breath.

The universe inflated from almost nothing by 10<+>50 in less than a billion trillion trillionth of a second before slowing to merely expand at colossal speed. Which could explain why it is so "smooth", the same microwave temperature everywhere, a quality which has puzzled cosmologists for decades. Kirshner, true scientist, applies the standard yardstick for smoothness. A baby's bottom, he reveals, has bumps of 0.1mm over a span of 10cm so is smooth to one part in 1,000, or 100 times rougher than the infant universe. That's without the nappy rash.

Six of the best

1 Small World, Mark Buchanan

The internet, the brain, the global economy and the stranger on the train who knows your aunt Gladys are all part of the same phenomenon The odds? 6/1

2 Reckoning with Risk, Gerd Gigerenzer

Why do we worry about meningitis but not about crossing the road? How do you make sense of cancer screening or HIV hazards? The odds? 7/2

3 The Extravagant Universe, Robert Kirshner

The universe is expanding faster and faster. Blame it on dark energy - and find out how much you can learn from an exploding star The odds? 7/1

4 Right Hand, Left Hand, Chris McManus

Why do some people write script from right to left? Are southpaws sinister, or just gauche? Is the whole universe asymmetric? The odds? 3/1

5 The Blank Slate, Steven Pinker

Bodies are the product of evolution, why not minds? We may have arrived trailing not just clouds of glory, but something called human nature The odds? 2/1 favourite

6 Where is Everybody?, Stephen Webb

If aliens are smarter than us, why haven't they moved in? Or at least tried to get in touch. Fifty answers to the intergalactic paradox The odds? 5/1

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