Theories without facts may be barren, but facts without theories are meaningless.

[on the theory of the firm] It is exactly analogous to the analysis of the reactions of a consumer by means of indifferent curves. Indeed, a consumer is merely a 'firm' whose product is 'utility.'

Anyone who believes exponential growth can go on forever in a finite world is either a madman or an economist.

A somewhat casual observer from outer space might well deduce that the course of evolution in this planet had produced a species of large four-wheeled bugs with detachable brains; peculiar animals which rested when they sent their brains away from them but performed in rather predictable manner when their brains were recalled.

Knowledge exists in minds, not in books. Before what has been found can be used by practitioners, someone must organize it, integrate it, extract the message.

Mathematicians themselves set up standards of generality and elegance in their exposition which are a bar to understand.

The organizer who creates roles, who creates the holes that will force the pegs to their shape, is a prime creator of personality itself. When we ask of a man, "What is he?" the answer is usually given in terms of his major role, job, or position in society; he is the place that he fills, a painter, a priest, a politician, a criminal.