Sometimes one pays most for the things one gets for nothing.

Don't listen to the person who has the answers; listen to the person who has the questions.

One does not make wars less likely by formulationg rules of warfare... war cannot be humanized. It can only be eliminated.

Make everything as simple as possible, but not simpler. A man should look for what is, and not for what he thinks should be. We cannot solve our problems with the same thinking we used when we created them. A question that sometimes drives me hazy: am I or are the others crazy? Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction. All religions, arts and sciences are branches of the same tree. It's not that I'm so smart, it's just that I stay with problems longer.

The most aggravating thing about the younger generation is that I no longer belong to it.

If the bee disappeared off the surface of the globe, then man would have only four years of life left. No more bees, no more pollination, no more plants, no more animals, no more man.

A perfection of means, and confusion of aims, seems to be our main problem.