Sex was invented as a biological instrument by (say) the green algae. But as an instrument in the ascent of man which is basic to his cultural evolution, it was invented by man himself.

Nations in their great ages have not been great in art or science, but in art and science.

I grew up to be indifferent to the distinction between literature and science, which in my teens were simply two languages for experience that I learned together.

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.

The child is not a prisoner of its inheritance; it holds its inheritance as a new creation which its future actions will unfold.

Science, like art, is not a copy of nature but a re-creation of her.

Has there ever been a society which has died of dissent? Several have died of conformity in our lifetime.