There is one ray of hope. It seems to me that today the responsible leaders of the several peoples have, in the main, the honest will to abolish war.

A hundred times every day I remind myself that my inner and outer life are based on the labors of others.

This is too difficult for a mathematician. It takes a philosopher. The hardest thing in the world to understand is the income tax.

Imagination is more important than knowledge. Knowledge is limited. Imagination encircles the world.

If at first the idea is not absurd, then there is no hope for it.

The secret to creativity is knowing how to hide your sources.

Since the mathematicians have invaded the theory of relativity I do not understand it myself any more.