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.

An ounce of algebra is worth a ton of verbal argument.

While I do not suggest that humanity will ever be able to dispense with its martyrs, I cannot avoid the suspicion that with a little more thought and a little less belief their number may be substantially reduced.

A time will however come (as I believe) when physiology will invade and destroy mathematical physics, as the latter has destroyed geometry.

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

Every Christian church has tried to impose a code of morals of some kind for which it has claimed divine sanction. As these codes have always been opposed to those of the gospels a loophole has been left for moral progress such as hardly exists in other religions.

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.