We animals are the most complicated things in the known universe.

The evidence for evolution is so compelling that the only way to save the creation theory is to assume that God deliberately planted enormous quantities of evidence to make it look as if evolution had happened.

I do not believe there is an atheist in the world who would bulldoze Mecca-or Chartres, York Minster or Notre Dame, the Shwe Dagon, the temples of Kyoto or, of course, the Buddhas of Bamiyan.

Nowadays theologians aren't quite so straightforward as Paley. They don't point to complex living mechanisms and say that they are self-evidently designed by a creator, just like a watch. But there is a tendency to point to them and say 'It is impossible to believe' that such complexity, or such perfection, could have evolved by natural selection. Whenever I read such a remark, I always feel like writing 'Speak for yourself' in the margin.

So it is best to keep an open mind and be agnostic. At first sight that seems an unassailable position, at least in the weak sense of Pascal's wager. But on second thoughts it seems a cop-out, because the same could be said of Father Christmas and tooth fairies. There may be fairies at the bottom of the garden. There is no evidence for it, but you can't prove that there aren't any, so shouldn't we be agnostic with respect to fairies?

The true scientific understanding of the nature of existence is so utterly fascinating; how could you not want people to share it? Carl Sagan, I think, said 'when you're in love, you want to tell the world.' And who, on understanding a scientific view of reality, would not, as it were, fall in love and want to tell the world.

I just would like to say that over more than a quarter-century as a scientist and a believer, I find absolutely nothing in conflict between agreeing with Richard [Dawkins] in practically all of his conclusions about the natural world, and also saying that I am still able to accept and embrace the possibility that there are answers that science isn't able to provide about the natural world - the questions about why instead of the questions about how. I'm interested in the whys.