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.

It has been the fashion to speak of the conflict between human rights and property rights, and from this it has come to be widely believed that the use of private property is tainted with evil and should not be espoused by rational and civilized men... the only dependable foundation of personal liberty is the personal economic security of private property. The Good Society.

Inevitably our opinions cover a bigger space, a longer reach of time, a greater number of things, than we can directly observe. They have, therefore, to be pieced together out of what others have reported and what we can imagine.

The only feeling that anyone can have about an event he does not experience is the feeling aroused by his mental image of that event ... For it is clear enough that under certain conditions men respond as powerfully to fictions as they do to realities.

The man who raises new issues has always been distasteful to politicians. He musses up what had been so tidily arranged.

A man who has humility will have acquired in the last reaches of his beliefs the saving doubt of his own certainty.

Unless the reformer can invent something which substitutes attractive virtues for attractive vices, he will fail.