All sorts of bodily diseases are produced by half-used minds.

Principles without programs are platitudes.

You can rave about Stravinsky without the slightest risk of being classified as a lunatic by the next generation .

Never waste jealousy on a real man: it is the imaginary man that supplants us all in the long run.

What we want is to see the child in pursuit of knowledge, and not knowledge in pursuit of the child.

I ... must continue to strive for more knowledge and more power, though the new knowledge always contradicts the old and the new power is the destruction of the fools who misuse it.

The conversion of Paul was no conversion at all; it was Paul who converted the religion that has raised one man above sin and death.