I am sometimes shocked by the blasphemies of those who think themselves pious.

To think I have spent my life on absolute muck.

Against my will, in the course of my travels, the belief that everything worth knowing was known at Cambridge gradually wore off. In this respect my travels were very useful to me.

Opinions which justify cruelty are inspired by cruel impulses.

Collective wisdom, alas, is no adequate substitute for the intelligence of individuals. Individuals who opposed received opinions have been the source of all progress, both moral and intellectual. They have been unpopular, as was natural.

Religions, which condemn the pleasures of sense, drive men to seek the pleasures of power. Throughout history power has been the vice of the ascetic.

The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts.