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.

It is the same with people as it is with riding a bike. Only when moving can one comfortably maintain one's balance.

Creativity is contagious. Pass it on.

Yes, we now have to divide up our time like that, between politics and our equations. But to me our equations are far more important, for politics are only a matter of present concern. A mathematical equation stands forever.

Everybody should be ashamed who uses the wonders of science and engineering without thinking and having mentally realized not more of it than a cow realizes of the botany of the plants which it eats with pleasure.

Small is the number of people who see with their eyes and think with their minds.

I very rarely think in words at all. A thought comes, and I may try to express in words afterwards.