Love is a better teacher than duty.

It takes a touch of genius - and a lot of courage to move in the opposite direction.

Infinite striving to be the best is man's duty; It is its own reward. Everything else is in god's hands. It's not that I'm so smart, it's just that I stay with problems longer.

If a theory can not be explained to a child, then the theory is probably worthless.

One is born into a herd of buffaloes and must be glad if one is not trampled under foot before one's time.

Since I have introduced this term I had always a bad conscience. . . . I cannot help to feel it strongly and I am unable to believe that such an ugly thing should be realized in nature.

I cannot imagine a God who rewards and punishes the objects of his creation and is but a reflection of human frailty.