In my experience, the best creative work is never done when one is unhappy.

The whole of science is nothing more than a refinement of everyday thinking.

Try not to become a man of success, but a man of value. Look around at how people want to get more out of life than they put in. A man of value will give more than he receives. Be creative, but make sure that what you create is not a curse for mankind.

The gift of fantasy has meant more to me than my talent for absorbing positive knowledge.

The American lives even more for his goals, for the future, than the European. Life for him is always becoming, never being.

Conviction is a good motive, but a bad judge.

We scientists, whose tragic destination has been to help in making the methods of annihilation more gruesome and more effective, must consider it our solemn and transcendent duty to do all in our power in preventing these weapons from being used for the brutal purpose for which they were invented.