What makes a free thinker is not his beliefs, but the way in which he holds them. If he holds them because his elders told him they were true when he was young, or if he holds them because if he did not he would be unhappy, his thought is not free; but if he holds them because, after careful thought, he finds a balance in their favor, then his thought is free, however odd his conclusions may seem.

This idea of weapons of mass extermination is utterly horrible and is something which no one with one spark of humanity can tolerate.

Sir Arthur Eddington deduces religion from the fact that atoms do not obey the laws of mathematics. Sir James Jeans deduces it from the fact that they do.

Awareness of universals is called conceiving, and a universal of which we are aware is called a concept.

The philosophies that have been inspired by scientific technique are power philosophies, and tend to regard everything non-human as mere raw material. Ends are no longer considered; only the skillfulness of the process is valued. This also is a form of madness. It is, in our day, the most dangerous form, and the one against which a sane philosophy should provide an antidote

Fools and fanatics are always so certain of themselves.

No one gossips about other people's secret virtues.