The factor in human life provocative of a noble discontent is the gradual emergence of a sense of criticism, founded upon appreciation of beauty, and of intellectual distinction, and of duty.

All practical teachers know that education is a patient process of mastery of details, minute by minute, hour by hour, day by day.

Philosophy asks the simple question: What is it all about?

Seek simplicity but distrust it.

The worst that happened to men of science was that Galileo suffered an honorable detention and a mild reproof, before dying peacefully in his bed.

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

The difference between ancients and moderns is that the ancients asked what have we experienced, and moderns asked what can we experience.