Thursday Book: So why does religion exist?

THE DARWIN WARS: HOW STUPID GENES BECAME SELFISH GODS BY ANDREW BROWN, SIMON & SCHUSTER, pounds 12.99

THE OTHER week I was at a lunch where a multimillionaire computer scientist wondered, "what is different about the genes in Silicon Valley that they can create so many more millionaires than we can in Britain?" I could have replied that it probably had little to do with genes and a lot to do with the better weather, a low-cost economy and ease of access to venture capital. But that would have been preaching to the uninterested - a practice only marginally less rewarding than doing so to the converted or the stupid. Indeed, you can't throw a book these days without hitting someone who is prepared to tell you that genes hold the answers to everything we do, where we have come from, and where we are going.

Andrew Brown would attach no little part of the blame for this to Richard Dawkins, whose 1976 book The Selfish Gene has shaped a generation's thinking about those little stretches of DNA that, er, well, control us in some way, don't they? The next time a non-scientist starts spouting to you about genes and DNA, see if he or she in fact knows what a gene does. If they answer "makes proteins", award half a point; if they answer "carries the code for a protein", the full point. If the answer is neither of those, a kick under the table is in order, to get them to shut up.

Dawkins's success, quickly followed by the rise to prominence of names such as Stephen Jay Gould, Edward (EO) Wilson, Daniel Dennett and Steven Pinker among the popular science-writing evolutionary-biologist crowd, has not brought with it much real enlightenment among the public about what genes, selfish or not, really do, or how they affect and are affected by the process of evolution. Nor has it even cleared up which of our human qualities we owe to unconscious evolution, and which to the culture that we have created with language and our intelligence.

Indeed, the arguments over this latter point are so intense that they have allowed Brown (a former writer for The Independent) plenty of room to examine the bitter feuds that rage between the two camps. He classes them as the "Dawkinsians" and the "Gouldians": hence The Darwin Wars.

If spats between academics were all there was to it, this could be a dull book. Happily, Brown is never satisfied with the rodomontade, and he frequently writes like an angel. (He also puts footnotes where they should be, at the bottom of the page rather than at the end of the chapter, and uses them to entertain and inform.) I laughed aloud at Brown's imagined description of Dawkins's birth: "The good fairy gave him good looks, intelligence, charm, and a chair at Oxford specially endowed for him. The bad fairy studied him for a while and said: `Give him a gift for metaphor.'" The point is that, in Dawkins's somewhat Humpty-Dumptyish use, neither of the words "selfish" and "gene" means what you or I (or even the person you kick under the table) normally mean. But it's a great metaphor. Ditto ideas such as the "blind watchmaker" of evolution, which to the unprepared reader raises a teleological point: whence the watchmaker?

While describing the battle lines and forays, mostly conducted via the correspondence column of the New York Review of Books, Brown himself gets involved in a bit of the fighting, laying waste to the idea of the "meme" - often touted as the "idea" counterpart of a gene or virus. A meme is described as a concept that will pass from mind to mind and thrive in the correct environment. Some evolutionary scientists love this idea (indeed, this morning another book entirely devoted to it thudded on to my desk) but, as Brown points out, the concept is too sloppily defined to have any true value.

Besides, its popularity among middle-class undergraduates having their first hit of marijuana should demonstrate its uselessness. Still, it does offer the pleasure of a chapter entitled "And the meme raths outgrabe".

Even better, Brown's fascination with the world of religion and morality leads him to use this debate as a means of examining the questions of why, if we are ruled by selfish genes, the intensely human qualities of mercy, faith, and admixtures of tolerance can exist.

Most biologists simply dismiss religion; but dismissing something because you think it is stupid is not the same as explaining why it exists.

These chapters form the heart of the book, which Brown sums up later by saying that "Most of this book has been concerned with scientists doing philosophy more or less badly, with occasional diversions to watch philosophers attempting science." I conclude that both are good only in their areas of specialisation. It must be something in the genes.