Most people say that it is the intellect which makes a great scientist. They are wrong: it is character.

People love chopping wood. In this activity one immediately sees results.

The faster you go, the shorter you are.

I used to go away for weeks in a state of confusion.

There could be no fairer destiny for any physical theory than that it should point the way to a more comprehensive theory in which it lives on as a limiting case.

It stands to the everlasting credit of science that by acting on the human mind it has overcome man's insecurity before himself and before nature.