His latest book of musings, the elegantly designed Religion for Atheists, has the potential to become his biggest-selling title yet. According to the dust-jacket blurb: ''Alain de Botton's inspiring book boldly argues that the supernatural claims of religion are entirely false - and yet religions still have some very important things to teach the secular world.'' The man will be in Sydney next month on another speaking tour, no doubt stumping up sales. Yet, famously, de Botton is one of the few writers in the world who can afford never to sell a single book. His Australian publishers had warned me that ''Alain doesn't like to talk about his private life''. Presumably, this is a reference to the fact his father, Gilbert de Botton (a Jewish banker who was born in Egypt but moved to Switzerland to head Rothschild Bank before founding Global Asset Management), provided for Alain with a $400 million-plus trust fund. Naturally, this has provoked both jealousy and ire from writers whose parents were somewhat less financially endowed. Even though the son claims to have left the trust fund untouched, earning his own keep from his writing and entrepreneurial activities, de Botton continues to attract vindictive verbal assaults. (One Guardian critic called him ''a slap-headed, ruby-lipped pop philosopher who's forged a lucrative career stating the bleeding obvious''.) Though de Botton had an ethically Jewish upbringing, he quickly corrects my assumption that he was raised in the Jewish religion. ''Oh no, I was brought up in a very atheistic Jewish family,'' he says. ''My father was like [fellow atheist author] Richard Dawkins's [father] - very fiercely anti-religion.''

Now de Botton is a father himself, of two boys aged seven and five. So, as a committed atheist, what does he tell them about religion? Is he dogmatic? Or does he protect their innocence, knowing they will make up their own minds when they are older? ''That's interesting,'' he says, momentarily nonplussed. ''Obviously it has just been Christmas, so they were in a nativity play, and there were lots of carols going on. You can't get away from it. But I suppose I try to explain it in a naturalistic way. I say: 'There's something called religion and it was invented a long time ago by people who felt very out of control with their lives, who didn't know … why the sun always rose over the mountains. Nowadays people don't find religion so convincing any more. ''But at the same time, I tell my children what I think myself. That religion is not necessarily convincing but it is still interesting and not to be laughed at or denigrated. That is the message of the book - that religious people are not crazy or evil or bad.'' So did he tell his sons Santa doesn't exist? ''They seem to have come to their own conclusions about Santa Claus. When my wife occasionally said things like, 'Be good, otherwise Santa won't give you any presents,' they just said, 'Don't be stupid.' They are utterly unconvinced and cynical, way ahead of me [at the same age].'' Of course, de Botton is hardly the first Oxbridge-educated atheist in the past decade to declare profitably that God is dead.

Apart from Dawkins's The God Delusion (2009) and the late Christopher Hitchens's God Is Not Great (2007), A.C. Grayling has also graced the world's bestseller lists with his more nuanced views. So why do we need another book? And what makes de Botton's 318-page essay different? ''There's been this very oppressive strand - and, as you say, it is a British elite movement led by men in their 60s, a very tight demographic,'' he says. ''Most of these books spend 400 pages hammering home this point [that God doesn't exist]. That anyone who thinks God does exist is an idiot. What about the resurrection? It's clearly nonsense. ''Their entire time is spent knocking religion. It's as if that is all they think being an atheist means. ''My starting point is: hang on a minute, guys. Do we really need to do this? Is it really so important to spend the whole time just mocking? As atheists, let's take the next step: atheism 2.0. Yes, it is true religion isn't scientifically accurate. But is there something interesting here for the secular world to learn from? ''For too long, it seems, being an atheist has meant that you believe that in the secular world we've got everything sorted out. That we are completely able to live [a full life] with technology, romantic love and television.

''But, of course, the modern world has lots of problems. Some of those problems could at least be alleviated by lessons from religion. I see religion as a storehouse of lots of really good ideas that a secular world should look at, raid and learn from.'' According to de Botton, this is a daring stance. ''Obviously my book is going to upset two camps,'' he says. ''Religious people, who are going to say: 'How can you steal our ideas but not believe? That's horrible, heretical.' To which my answer is: why do we need to believe it? Why can't we just learn from it? ''The other people who will get upset are those fierce atheists who will say: 'Don't spend any time considering religion's [good points]. The whole thing is just poisonous.' To which my answer is: 'No, some bits may be. But not the whole thing.''' At this point, it is time to play devil's advocate. Or maybe God's advocate? Could this entire, vitriolic debate between Oxbridge's brightest be out of kilter with the real world? Surely, there is a large proportion of any Christian congregation, for example, that wouldn't sign off on the literal truth of the Virgin Birth.

Likewise, most atheists recognise our modern secular world has been shaped by the Bible, the Torah, the Koran, Buddhist texts and the collective wisdom of the ancients. Aren't most of us in Western society - religious or atheist - relaxed with the cliche that what unites us is greater than that which divides us? That educated Westerners (at whom the book is aimed) overwhelmingly accept that the finest ground rules for an admittedly imperfect society (as well as some of the worst) were first defined by the rabbi, monk, mullah or swami? ''I don't think it is as relaxed as that,'' de Botton says. ''My experience is that a lot of people will say this: 'Is the modern world shallow and spiritually empty in lots of ways?' Yes, broad agreement: 'We are materialistic, goal-oriented. But what else is there?' Religion? 'No, that is unbelievable. I went to church and couldn't swallow it. The music was nice but I don't belong there. I tried Buddhism but Buddhism believes in reincarnation and the worship of supernatural deities and I couldn't swallow that, either.' ''So they are searching. Perhaps they have children and want to teach them a moral code. The Ten Commandments? That's not going to work. Nor is the Koran or some Buddhist text. ''So these people are stuck between the religious world and the secular, modern world. And it is those people I am addressing in this book. And I think they are quite widespread.''

Religion for Atheists will be published on January 25 by Hamish Hamilton, $35. Alain de Botton will speak at the Sydney Opera House on February 23.