I have suffered a great deal from writers who have quoted this or that sentence of mine either out of its context or in juxtaposition to some incongruous matter which quite distorted my meaning, or destroyed it altogether.

The point of mathematics is that in it we have always got rid of the particular instance, and even of any particular sorts of entities. So that for example, no mathematical truths apply merely to fish, or merely to stones, or merely to colours. So long as you are dealing with pure mathematics, you are in the realm of complete and absolute abstraction. . . . Mathematics is thought moving in the sphere of complete abstraction from any particular instance of what it is talking about.

A man of science doesn't discover in order to know, he wants to know in order to discover.

The importance of an individual thinker owes something to chance. For it depends upon the fate of his ideas in the minds of his successors.

Religion is the last refuge of human savagery.

Inventive genius requires pleasurable mental activity as a condition for its vigorous exercise

The absolute pacifist is a bad citizen; times come when force must be used to uphold right, justice and ideals.