I have never yet met a healthy person who worried very much about his health, or a really good person who worried much about his own soul.

There is no great invention, from fire to flying, which has not been hailed as an insult to some god.

A discussion between Haldane and a friend began to take a predictable turn. The friend said with a sigh, 'It's no use going on. I know what you will say next, and I know what you will do next.' The distinguished scientist promptly sat down on the floor, turned two back somersaults, and returned to his seat. 'There,' he said with a smile. 'That's to prove that you're not always right.'

Until politics are a branch of science, we shall do well to regard political and social reforms as experiments rather than short-cuts to the millennium.

There are 400,000 species of beetles on this planet, but only 8,000 species of mammals.

Shelley and Keats were the last English poets who were at all up to date in their chemical knowledge.

I think, however, that so long as our present economic and national systems continue, scientific research has little to fear.