Whenever you find yourself getting angry about a difference of opinion, be on your guard; you will probably find, on examination, that your belief is going beyond what the evidence warrants.

Force plays a much larger part in the government of the world than it did before 1914, and what is especially alarming, force tends increasingly to fall into the hands of those who are enemies of civilization.

The triumph of science has been mainly due to its practical utility, and there has been an attempt to divorce this aspect from that of theory, thus making science more and more a technique, and less and less a doctrine as to the nature of the world. The penetration of this point of view to philosophers is very recent.

The life of man is a long march through the night, surrounded by invisible foes, tortured by weariness and pain, towards a goal that few can hope to reach, and where none may tarry long.

Are you never afraid of God's judgement in denying him? Most certainly not. I also deny Zeus and Jupiter and Odin and Brahma, but this causes me no qualms. I observe that a very large portion of the human race does not believe in God and suffers no visible punishment in consequence. And if there were a God, I think it very unlikely that He would have such an uneasy vanity as to be offended by those who doubt His existence.

(on A History of Western Philosophy) I was sometimes accused by reviewers of writing not a true history but a biased account of the events that I arbitrarily chose to write of. But to my mind, a man without a bias cannot write interesting history - if, indeed, such man exists.

[Regarding] the convention that clergymen are more virtuous than other men. Any average selection of mankind, set apart and told that it excels the rest in virtue, must tend to sink below the average.