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.

There are two parts to the human dilemma. One is the belief that the end justifies the means. That push-button philosophy, that deliberate deafness to suffering, has become the monster in the war machine. The other is the betrayal of the human spirit: the assertion of dogma that closes the mind, and turns a nation, a civilization, into a regiment of ghosts--obedient ghosts or tortured ghosts.

The men who made the Industrial Revolution are usually pictured as hardfaced businessmen with no other motive than self-interest. That is certainly wrong. For one thing, many of them were inventors who had come into business that way.

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

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

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

There must be something unique about man because otherwise, evidently, the ducks would be lecturing about Konrad Lorenz, and the rats would be writing papers about B. F. Skinner.