Give back to the world at least what you've received.

This is a question too difficult for a mathematician. It should be asked of a philosopher"(when asked about completing his income tax form)

For the most part, I do the thing which my own nature prompts me to do. It is embarrassing to earn so much respect and love for it.

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.

Don't wait for miracles, your whole life is a miracle.

The state is made for man, not man for the state.... That is to say, the state should be our servant and not we its slaves

When you are courting a nice girl an hour seems like a second. When you sit on a red-hot cinder a second seems like an hour. That's relativity.