I like mathematics because it is not human and has nothing particular to do with this planet or with the whole accidental universe - because, like Spinoza's God, it won't love us in return.

Many people when they fall in love look for a little haven of refuge from the world, where they can be sure of being admired when they are not admirable, and praised when they are not praiseworthy.

Boys and young men acquire readily the moral sentiments of their social milieu, whatever these sentiments may be.

I do so hate to leave this world.

When a man acts in ways that annoy us we wish to think him wicked, and we refuse to face the fact that his annoying behavior is the result of antecedent causes which, if you follow them long enough, will take you beyond the moment of his birth, and therefore to events for which he cannot be held responsible by any stretch of imagination... When a motorcar fails to start, we do not attribute its annoying behavior to sin, we do not say, you are a wicked motorcar, and you shall not have any more gasoline until you go.

For a good notation has a subtlety and suggestiveness which at times make it seem almost like a live teacher.

The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt. Even those of the intelligent who believe that they have a nostrum are too individualistic to combine with other intelligent men from whom they differ on minor points.