I do not pretend to be able to prove that there is no God. I equally cannot prove that Satan is a fiction. The Christian god may exist; so may the gods of Olympus, or of ancient Egypt, or of Babylon. But no one of these hypotheses is more probable than any other: they lie outside the region of even probable knowledge, and therefore there is no reason to consider any of them.

Only mathematics and mathematical logic can say as little as the physicist means to say.

Religions which have any very strong hold over men's actions have generally some instinctive basis.

The modern man thinks that everything ought to be done for the sake of something else, and never for its own sake.

Our use of the phrase 'The Dark Ages' to cover the period from 600 to 1000 marks our undue concentration on Western Europe. [...] From India to Spain, the brilliant civilisation of Islam flourished. What was lost to Christendom at this time was not lost to civilisation, but quite the contrary. [...] To us it seems that West-European civilisation is civilisation, but this is a narrow view.

One of the symptoms of an approaching nervous breakdown is the belief that one's work is terribly important.

Is a man what he seems to the astronomer, a tiny lump of impure carbon and water crawling impotently on a small and unimportant planet? Or is he what he appears to Hamlet? Is he perhaps both as once?