The idea of protoplasm, which was really a name for our ignorance, [is] only a little less misleading than the expression "Vital force".

Science is vastly more stimulating to the imagination than the classics.

Blake expressed some doubt as to whether God had made the tiger. But the tiger is in many ways an admirable animal. We have now to ask whether God made the tapeworm. And it is questionable whether an affirmative answer fits in either with what we know about the process of evolution or what many of us believe about the moral perfection of God.

Haldane was engaged in discussion with an eminent theologian. "What inference," asked the latter, "might one draw about the nature of God from a study of his works?" Haldane replied: "An inordinate fondness for beetles."

We do not know, in most cases, how far social failure and success are due to heredity, and how far to environment. But environment is the easier of the two to improve.

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.

Would I lay down my life to save my brother? No, but I would to save two brothers or eight cousins.