They come into being not through demonstration but through revelation, through the medium of powerful personalities.

Mathematics are well and good but Nature keeps dragging us around by the nose.

Cherish the questions, for the answers keep changing.

It is the supreme art of the teacher to awaken joy in creative expression and knowledge.

Gravitation is not responsible for people falling in love.

I do not believe in free will. Schopenhauer's words: 'Man can do what he wants, but he cannot will what he wills,' accompany me in all situations throughout my life and reconcile me with the actions of others, even if they are rather painful to me. This awareness of the lack of free will keeps me from taking myself and my fellow men too seriously as acting and deciding individuals, and from losing my temper.

Imagination is more valuable than information.