In my experience, the best creative work is never done when one is unhappy.

What interests me most is whether God could have made the world differently.

A little knowledge is a dangerous thing. So is a lot.

Fantasie is belangrijker dan kennis, want kennis is begrensd.

If I had my life to live over again, I would elect to be a trader of goods rather than a student of science. I think barter is a noble thing.

The feeling for what ought and ought not to be grows and dies like a tree, and no fertilizer of any kind will do much good. What the individual can do is give a fine example, and have the courage to firmly uphold ethical convictions in a society of cynics. I have for a long time tried to conduct myself this way, with varying success.

Thought is the organizing factor in man, intersected between the causal primary instincts and the resulting actions.