You can't imagine how gratifying it is to have a reader come up to you and say, 'You changed my life.'

Five per cent vision is better than no vision at all. Five per cent hearing is better than no hearing at all. Five per cent flight efficiency is better than no flight at all. It is thoroughly believable that every organ or apparatus that we actually see is the product of a smooth trajectory through animal space, a trajectory in which every intermediate stage assisted survival and reproduction.

Gravity is not a version of the truth. It is the truth. Anyone who doubts it is invited to jump out a tenth-storey window.

We have sexual lust even though we know perfectly well that, because we're using contraception, it is not going to result in the propagation of our genes. That doesn't matter, because the lust was built into our brains at a time when there was no contraception.

I am agnostic only to the extent that I am agnostic about fairies at the bottom of the garden

Real life seeks the gentle slopes at the back of Mount Improbable, while creationists are blind to all but the daunting precipice at the front.

The less you think, the more you believe.