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.

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

Satire is not a social dynamite. But it is a social indicator: it shows that new men are knocking at the door.

The human baby, the human being, is a mosaic of animal and angel.

One original thought is worth the sum total of human knowledge, because it advances the sum total of human knowledge by that one original thought.

You will die but the carbon will not; its career does not end with you. It will return to the soil, and there a plant may take it up again in time, sending it once more on a cycle of plant and animal life.

The most powerful drive in the ascent of man is his pleasure in his own skill. He loves to do what he does well. And having done it well, he loves to do it better.