Curiosity is a delicate little plant that, aside from stimulation, stands mainly in need of freedom.

We should take care not to make the intellect our god; it has, of course, powerful muscles, but no personality.

The sceptic will say, 'It may well be true that this system of equations is reasonable from a logical standpoint, but this does not prove that it corresponds to nature.' You are right, dear sceptic. Experience alone can decide on truth.

An expert is a person who has few new ideas; a beginner is a person with many.

I am also convinced that one gains the purest joy from spirited things only when they are not tied in with earning one's livelihood.

By an application of the theory of relativity to the taste of readers, today in Germany I am called a German man of science, and in England I am represented as a Swiss Jew. If I come to be represented as a bête noire, the descriptions will be reversed, and I shall become a Swiss Jew for the Germans and a German man of science for the English!

The monotony and solitude of a quiet life stimulates the creative mind.