To me the most interesting thing about man is that he is an animal who practices art and science and in every known society practices both together.

Revolutions are not made by fate but by men.

To me, being an intellectual doesn't mean knowing about intellectual issues; it means taking pleasure in them.

When Da Vinci wanted an effect, he willed, he planned the means to make it happen: that was the purpose of his machines. But the machines of Newton ... are means not for doing but for observing. He saw an effect, and he looked for its cause.

We gain our ends only with the laws of nature; we control her only by understanding her laws.

The basis for poetry and scientific discovery is the ability to comprehend the unlike in the like and the like in the unlike.

The paradox of knowledge is not confined to the small, atomic scale; on the contrary, it is as cogent on the scale of man, and even of the stars.