DNA is ROM. It can be read millions of times over, but only written to once - when it is first assembled the birth of the cell in which it resides.

Why do more than 40 percent of Americans think that the Universe began after the domestication of the dog?

I'm a sucker for nice religious leaders. I fall for it every time.

Commonsense lets us down, because commonsense evolved in a world where nothing moves very fast, and nothing is very small or very large; the mundane world of the familiar.

When I am dying, I should like my life taken out under general anaesthetic, exactly as if it were a diseased appendix.

Two religions cannot both be right, because they contradict each other, yet they can both be wrong.

As my colleague, the physical chemist Peter Atkins, puts it, we must be equally agnostic about the theory that there is a teapot in orbrit around the planet Pluto. We can't disprove it. But that doesn't mean the theory that there is a teapot is on level terms with the theory that there isn't.