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

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.

Religion will not regain its old power until it can face change in the same spirit as does science.

The merely well-informed man is the most useless bore on God's earth.

But you can catch yourself entertaining habitually certain ideas and setting others aside; and that, I think, is where our personal destinies are largely decided.

There are no whole truths: All truths are half-truths.

The purpose of education is not to fill a vessel but to kindle a flame.