And the beauty of the anthropic principle is that it tells us, against all intuition, that a chemical model need only predict that life will arise on one planet in a billion billion to give us a good and entirely satisfying explanation for the presence of life here.

In two senses: One is that you cannot go on the street and shout that you are an atheist, the other is that you are never given the intellectual framework for calling your faith into question.

The Roman Catholic Church is an institution for whose gains the phrase "ill-gotten" might have been specially invented. And of all its money-making rip-offs, the selling of indulgences must surely rank among the greatest con tricks in history, the medieval equivalent of the Nigerian Internet scam but far more successful.

We are going to die, and that makes us the lucky ones. Most people are never going to die because they are never going to be born. The potential people who could have been here in my place but who will in fact never see the light of day outnumber the sand grains of Sahara.

An Internet meme is a hijacking of the original idea. Instead of mutating by random change and spreading by a form of Darwinian selection, Internet memes are altered deliberately by human creativity. There is no attempt at accuracy of copying, as with genes - and as with memes in their original version.

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.

Compassionate doctors sometimes lie to patients about the severity of their condition, and it is not always wrong to do so.