No nation was ever so virtuous as each believes itself, and none was ever so wicked as each believes the other.

Power is sweet; it is a drug, the desire for which increases with a habit.

Admit at least one painful truth to yourself every day. Teach yourself to feel that life would still be worth living even if you were not immeasurably superior to all your friends. Exercises of this sort, prolonged through several years, will at last enable you to admit facts without flinching, and will, in so doing, free you from the empire of fear over a very large field.

It is impossible to read in America, except on a train, because of the telephone. Everyone has a telephone, and it rings all day and most of the night.

The happy life is to an extraordinary extent the same as the good life.

Science, in its ultimate ideal, consists of a set of propositions arranged in a hierarchy, the lowest level of the hierarchy being concerned with particular facts, and the highest with some general law, governing everything in the universe. The various levels in the hierarchy have a two-fold logical connection, travelling one up, one down; the upward connection proceeds by induction, the downward by deduction.

Mankind has become so much one family that we cannot insure our own prosperity except by insuring that of everyone else.