Reason is intuition's servant.

If you can't explain something simply, you don't know enough about it.

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.

There is possibility in every difficulty.

Peace cannot be kept by force. It can only be achieved by understanding. You cannot subjugate a nation forcibly unless you wipe out every man, woman, and child. Unless you wish to use such drastic measures, you must find a way of settling your disputes without resort to arms.

By academic freedom I understand the right to search for truth and to publish and teach what one holds to be true. This right implies also a duty: one must not conceal any part of what on has recognized to be true. It is evident that any restriction on academic freedom acts in such a way as to hamper the dissemination of knowledge among the people and thereby impedes national judgment and action.

Human beings are not condemned, because of their biological constitution, to annihilate each other or to be at the mercy of a cruel, self-inflicted fate.