It's no accident that capitalism has brought with it progress, not merely in production but also in knowledge. Egoism and competition are, alas, stronger forces than public spirit and sense of duty.

Where the world ceases to be the scene of our personal hopes and wishes, where we face it as free beings admiring, asking and observing, there we enter the realm of Art and Science.

A human being is part of a whole called by us the universe.

The flag is a symbol of the fact that man is still a herd animal.

I have deep faith that the principle of the universe will be beautiful and simple

If I were wrong, wouldn't one be enough?

I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones.