The daily struggle does not arise from a purpose or a program, but from an immediate need.

A theory is the more impressive the greater the simplicity of its premises is, the more different kinds of things it relates, and the more extended is its area of applicability. Therefore the deep impression which classical thermodynamics made upon me. It is the only physical theory of universal content concerning which I am convinced that within the framework of the applicability of its basic concepts, it will never be overthrown.

Any brief military advantage the USA might gain with nuclear weapons would be offset by political and psychological losses and damage to American prestige. The United States might even touch off a worldwide armaments race.

Hail to the man who went through life always helping others, knowing no fear, and to whom aggressiveness and resentment are alien. Such is the stuff of which the great moral leaders are made.

Life is a preparation for the future; and the best preparation for the future is to live as if there were none.

One must take what nature gives as one finds it.

The only rational way of educating is to be an example. If one can't help it, a warning example.