When everyone thinks the same, nobody is thinking.

Men have been barbarians much longer than they have been civilized. They are only precariously civilized, and within us there is the propensity, persistent as the force of gravity, to revert under stress and strain, under neglect or temptation, to our first natures.

Because the results are expressed in numbers, it is easy to make the mistake of thinking that the intelligence test is a measure like a foot ruler or a pair of scales. It is, of course, a quite different sort of measure. Intelligence is not an abstraction like length and weight; it is an exceedingly complicated notion - which nobody has yet succeeded in defining.

There is nothing so good for the human soul as the discovery that there are ancient and flourishing civilized societies which have somehow managed to exist for many centuries and are still in being though they have had no help from the traveler in solving their problems.

Brains, you know, are suspect in the Republican Party.

A man cannot sleep in his cradle: whatever is useful must in the nature of life become useless.

Ages when custom is unsettled are necessarily ages of prophecy. The moralist cannot teach what is revealed; he must reveal what can be taught. He has to seek insight rather than to preach.