Why is religion on the rise again?

For us atheists, something strange just happened. The entire Western world ground to a halt three days ago - at the start of the twenty-first century - to celebrate the birth of a 2000 year-old messiah. If you read the great anti-theist writers of the nineteenth and twentieth centuries - men like Ludwig Feuerbach, Karl Marx or Sigmund Freud - Jesus Christ and the Judaeo-Christian God should be a fading memory by now. They should have joined Zeus, Thor and Ra in the Cemetery for Dead Deities. Humanity should be entering a post-religious era of reason and enlightenment any moment now.

Instead, Christianity - along with the other major world religions - is resurgent. The United States is undergoing a "Second Great Awakening", where opinion polls suggest more Americans believe in creationism than evolution. The Arab world is pickled in an angry Islam. Jewish fundamentalists are even today building houses on stolen Palestinian land, on the grounds that it was given to them by God.

It used to be assumed that Western Europe set the pattern for the rest of the world, with our swelling secularism and closing churches. In fact, we look increasingly anomalous. Britain - with 12 per cent of the population declaring themselves atheist and another 43% per cent agnostic - is one of the few places where we non-believers can feel any hope at all. But even here, the religious faiths that do persist are becoming more extreme. Church of England mildness - the kind that admits most of the Bible is a metaphor - is waning, while faiths like Pentecostalism, which encourages speaking in tongues, are rising.

So how did an intellectual wave that seemed to be washing over the world suddenly recede? Why is atheism failing as a mass movement? Alister McGrath, author of the fascinating new book The Twilight of Atheism: The Rise and Fall of Disbelief in the Modern World, suggests an answer.

He believes that we don't need passionate, campaigning atheism any more because organised religion has been weakened. Personal faith has become largely privatised, a minor matter of individual consumer choice. It's easy to see why Galileo Galilei would despise a Vatican that incarcerated him for revealing basic scientific truths - but why would anybody get so upset about their watered-down ancestors?

So "in the Western European context, at least, a swelling public indifference toward religion has led to the loss of potency at both poles - Christianity and atheism," McGrath writes.

But is this true? It's certainly the case that, say, the Vatican no longer has tyrannical powers. A few lingering theocracies force their faith onto their citizens - Iran is a good example - but they are few and they are tottering. Yet it doesn't take long to list the victims of religion in the world today.

Let me name just a smattering of the people who will die next year as a direct result of the religious beliefs of others. Evangelical Christians in America have successfully campaigned to deny all US funding for abortion to developing countries, based on the archaic religious belief that "a soul" appears at the moment a sperm fertilises an egg. The result? The UN's population fund has been forced to close reproductive health clinics for some of the poorest women in the world - and condemned them in many cases to die in childbirth. Aid agencies working in the developing world estimate this religious policy is killing 10,000 women and children a year; some estimates run as high as 150,000.

Then there's the religious fundamentalist movement we have all been thinking about: al-Qa'ida. I've never been persuaded by the notion that they are not "true Muslims". It's certainly the case that most Muslims in the world don't agree with their interpretation of the Koran, and are as appalled as the rest of us by the murder of civilians. But the Koran is - like all religious texts - the vague and contradictory work of human beings. There are indeed passages that seem to support what Osama Bin Laden advocates; there are other passages that support the idea that Islam is a religion of peace. To say one is right and has stumbled onto the "true" essence of Islam is to make an unacceptable concession to the idea that there is a divine coherence to the Koran.

It's tempting to say extremists from Osama to Jerry Falwell are somehow "distorting" or "perverting" their religions - but often, they are simply following the guidance of the ugliest parts of their religious texts.

And on the list of religious victims goes. Does anybody think the Israel/Palestine conflict would be so hard to solve if the settlers, Hamas and everybody in between were atheists? Religion has inflated this conflict over real estate into a Holy War - and this pattern is repeated in trouble-spots across the world. So I don't buy McGrath's idea that there is no need for angry, proselytising anti-theists. The reason why atheism has failed must lie elsewhere.

An alternative explanation has emerged this year. The distinguished molecular biologist Dean Hamer claims to have discovered "a God gene" - a part of the brain that strongly correlates with feelings of spirituality. He believes some of us - a majority - are hard-wired to feel spiritual and to be open to a sense of transcendence. The sense there is something beyond and above them is encoded onto their DNA. Only a minority lacking this gene - that 12 per cent of Brits - can ever that we live in a totally material universe.

So is atheism doomed to be a minority pursuit for the next few millennia until we evolve a new set of genes? Richard Dawkins, Britain's most distinguished scientist-atheist, is very sceptical about the possibility of a God gene, but he has speculated that religious belief might be so persistent because at some point in the development of our species it gave humans an evolutionary advantage. The religious might have been more able to cope with stress or with the fear of death than the non-religious, or they might have been able to bond together more effectively in groups.

So, he explains, "The [persistence of] religious behaviour may be a misfiring, an unfortunate manifestation of an underlying psychological propensity that in other circumstances was once useful." I like the irony of this theory: evolution makes it possible for religious delusions like creationism to persist.

I'm not qualified to judge if these scientific theories are correct, but I fear the answer might be more depressing. It might just be that atheism is cold and tough and hard to live with.

It isn't easy to accept that we are arbitrarily evolved creatures living in an empty void, condemned to search for meaning where there is none. Life is more bearable if we enter into the comforting illusion that there is a source of meaning Somewhere Out There, just beyond our grasp.

So perhaps the great mistake Feuerbach, Marx and Freud made was to assume that people would prefer cold atheist truths to warm religious myths. Simone de Beauvoir described the process of losing her faith as "the world going silent". I can live with the silence - but most people, it seems, can't.

j.hari@independent.co.uk