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

I advocate world government because I am convinced that there is no other possible way of eliminating the most terrible danger in which man has ever found himself. The objective of avoiding total destruction must have priority over any other objective.

The important thing is not to stop questioning. Curiosity has its own reason for existing. One cannot help but be in awe when he contemplates the mysteries of eternity, of life, of the marvelous structure of reality. It is enough if one tries merely to comprehend a little of this mystery every day. Never lose a holy curiosity.

The strength of the Constitution lies entirely in the determination of each citizen to defend it. Only if every single citizen feels duty bound to do his share in this defense are the constitutional rights secure.

I am doing just fine, considering that I have triumphantly survived Nazism and two wives.

About God, I cannot accept any concept based on the authority of the Church... As long as I can remember. I have resented mass indoctrination. I cannot prove to you there is no personal God, but if I were to speak of him, I would be a liar. I do not believe in the God of theology who rewards good and punishes evil. His universe is not ruled by wishful thinking, but by immutable laws

Everything is energy and that’s all there is to it.