Andrew Copson, who runs the British Humanist Association, is a third generation post-Christian. "I grew up in a post-religious society in the Midlands. I went to an entirely secular primary school and secondary school; the popular culture I imbibed was things like Star Trek. I read fantasy and science fiction. I studied classics at university and some modern history."

He was talking at a small conference on the study of non-religion and secularity last week. Sociologists and anthropologists have done a great deal of research on different forms of belief. But unbelief, or at least a life untouched in any serious sense by organised religion, is only just coming into scope for this kind of social scientific inquiry.

Copson had a varied intellectual and social experience when he was growing up, but he says: "What didn't feature in any way in my account was religion. What's not in any sense contributed to making me what I am is religion, and I think that story is increasingly typical of non-religious people."

So it was quite a shock to him to move to south London and discover a place where a great many of the social services were provided with or through religious bodies.

This was part of a story he told last week, at a meeting of an academic group devoted to the study of non-religion, and of secularity as a sociological phenomenon. The story disconcerted me, productively: it made me realise the extent to which Greek, Latin and Christianity appear in one cultural bundle in my eyes. Of course there are lots of Christians who are ignorant of Greek, and probably still more of Latin, since many people learn New Testament Greek. But to learn Latin and Greek after an upbringing innocent of Christianity is something that was pretty much impossible in Europe during the last 1,500 years.

Another rather lazy assumption was dynamited later in the day by David Voas, the sociologist behind the informative British Religion in Numbers. He showed us any number of graphs showing a steady falling off of religious belief in England over the past 50 or 60 years, but ended with one in the shape of a shallow X. One line, sloping down from left to right, showed the familiar decline in religious belief. The other, sloping up over the same decades, showed the corresponding rise in a faith in life after death.

So what we have now is a country where large numbers of people repudiate religion, but are anyway convinced that there is some form of life after death. What they mean by saying they believe in "life after death" is of course almost impossible to say. But it is at least possible that the growth in a belief in life after death is connected with a declining belief in heaven, or at least hell.

Of course it's obvious that a belief in life after death is incompatible with materialism, and with all scientific understandings of consciousness. Our minds clearly seem dependent on our brains, and intimately dependent on their functioning.

So if the fundamental opposition is one between religion and scientific materialism, then we would expect faith in life after death to diminish along with a belief in heaven and hell as forming the moral poles of our existence. This hasn't happened. The X on Voas's graph marks the spot where it didn't happen. The conflict we're seeing is not between religion and science, since both are losing out to a kind of disorganisation of overlapping and contradictory fragments of wishful thinking.

In this light, the belief that the end of organised religion in and of itself leads to rationality comes to seem an article of faith: something useful, perhaps, for social cohesion, but not in fact literally true.

This is an old tune, of course. Whether it is persuasive probably depend on your belief in progress, which is itself a matter of temperament as much as anything else. But I can't say I find committed atheism is often accompanied by a commitment to careful reasoning. Atheists have their shibboleths like everyone else. Matthew Engelke, an anthropologist who spent a year studying the BHA, told a lovely story about the horror he unwittingly inspired in his subjects when he mentioned that he used a lotion from Neal's Yard: it seems that in some rationalists even the smallest traces of homoeopathy can paralyse the reason.

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