Quotes of the Day

What's the first thing you do if the ground beneath you starts to rumble and the walls begin to shake? Grab the kids and run? Check your home-insurance policy? Fall on your knees and pray for deliverance? All logical enough reactions, but not your very first one. Instead, even when faced with imminent disaster, you'll spend precious time asking, "What was that?" It's called the cognitive imperative, the uniquely human, hardwired instinct to link cause with effect that gave us a vital evolutionary advantage over other animal species. After all, the noise could be just a passing truck and nothing to lose precious sleep over.

Delineating how we react to an earthquake is just one example of the cognitive imperative described in Six Impossible Things Before Breakfast, British scientist Lewis Wolpert's enquiry into the evolutionary origins of belief. If the theme sounds familiar, that's because the search for scientific roots of religious faith is a hot, and heatedly debated, issue of the day. In his 2004 book The God Gene, U.S. molecular biologist Dean Hamer claimed to have located one of the genes he said was responsible for spirituality. Last month, the American philosopher and evolutionary theorist Daniel Dennett provoked more controversy with Breaking the Spell, in which he cast religion in terms of memes — cultural ideas that can spread, mutate and survive in our minds, whether or not they are good for us. Meanwhile in Oxford, England, researchers at the Centre for the Science of the Mind are subjecting volunteers to severe pain to see if religious belief can help them cope with physical suffering.

As a developmental biologist at London's University College, and one of Britain's loudest champions of the public understanding of science, Wolpert covers genes, memes, pain and various other angles in his book. But rather than just arm wrestling with God's faithful, his book attempts to survey the science underpinning all intuitive beliefs, including religion, that humans stubbornly cling to, in spite of the best efforts of rational enquiry to displace them: credence in the paranormal, magic and superstition; faith in alternative-health therapies; the conviction that sooner or later we're bound to win a lottery jackpot. Our belief engine, Wolpert concludes, works on wholly unscientific principles: "It prefers quick decisions, it is bad with numbers, loves representativeness and sees patterns where there is only randomness. It is too often influenced by authority and it has a liking for mysticism."

It is no coincidence that the stubbornest of our "irrational" beliefs correspond to our fears of the unknown, the unknowable and the unstoppable — of disease, death and natural disaster. Although Wolpert is a passionate promoter of science, he still recognizes that religion has its benefits and that in some things "reason will never triumph over superstition." The Nobel-prizewinning physicist Niels Bohr once explained why he kept a horseshoe nailed to his wall. It was not because he believed it would bring him good luck, but because he'd been told it would do so even if he didn't believe it. "How can one argue with such logic?" said Bohr. Wolpert, who took the title of his book from Lewis Carroll's Through the Looking Glass, in which the White Queen explains to Alice that believing in impossible things is simply a matter of practice, seems happy to agree.

More likely to start an argument is the author's novel proposition that the imperative to link cause and effect derived directly from our earliest hominid ancestors' discovery of tools as many as 2 million years ago. The ability to fashion a flint spear, he speculates, promoted a kind of causal thinking that was beyond other species: take a certain type of stone, hit it in just such a way, and it will leave a cutting edge. The later development of another tool, language, enabled early humans to explain the technology, and in the evolutionary twinkling of an eye we found ourselves genetically wired to seek a cause for every effect we see. In virtually no time at all, Archimedes was leaping from his bath.

By linking our belief engine to the use of tools, Wolpert suggests a more fruitful engagement between science and faith than the either/or conflict we're normally asked to take sides in. Wolpert, 76, was prompted to write the book by the shock of a conversation with his son Matthew, who had joined a fundamentalist Christian church. Matthew told his father he envied him because the elder Wolpert would die soon and get to heaven first. That logic still troubles the scientist, but the parent in him now accepts that the church was a great benefit to his son. Religious beliefs will endure, Wolpert writes, "not only because mysticism is in our brains, but also because it gives enormous comfort and meaning to life." So when your cognitive imperative tells you it is the ground beneath your certainties that is shaking, the good news is that there are other beliefs in the human toolbox you can try.

• MICHAEL BRUNTON
• A passionate rationalist explores the scientific roots of religious belief, superstition and plain old luck