You must bring out of each word its practical cash-value, set it at work within the stream of your experience.

We have lost the power even of imagining what the ancient idealization of poverty could have meant: the liberation from material attachments, the unbribed soul, the manlier indifference, the paying our way by what we are and not by what we have, the right to fling away our life at any moment irresponsibly - the more athletic trim, in short, the moral fighting shape.

If this life is not a real fight, in which something is eternally gained for the universe by success, it is no better than a game of private theatricals from which one may withdraw at will. But it feels like a real fight.

All our scientific and philosophic ideals are altars to unknown gods.

Philosophy is at once the most sublime and the most trivial of human pursuits. It works in the minutest crannies and it opens outthe widest vistas. It 'bakes no bread', as has been said, but it can inspire our souls with courage.

I believe there is no source of deception in the investigation of nature which can compare with a fixed belief that certain kinds of phenomena are IMPOSSIBLE.

A sense of humor is just common sense dancing.