Trend is not destiny.

Adventure is humdrum and routine unless one assimilates it, unless one relates it to a central core which grows within and gives it contour and significance. Raw experience is empty, just as empty as the forecastle of a whaler as in a chamber of a counting house; for it is not what one does, but in a manifold sense, what one realizes that keeps existence from being vain and trivial.

Every generation revolts against its fathers and makes friends with its grandfathers.

In war, the army is not merely a pure consumer, but a negative producer.

To the extent that the scientist's capacity for pursuing the truth depends upon costly apparatus, institutional collaboration and heavy capital investment by government or industry he is no longer his own master.

Nothing is unthinkable, nothing impossible to the balanced person, provided it comes out of the needs of life and is dedicated to life's further development.

Without leisure there can be neither art nor science nor fine conversation, nor any ceremonious performance of the offices of love and friendship.