Murray N. Rothbard
Money in a Free Society
1. The Value of Exchange
How did money begin? Clearly, Robinson Crusoe had no need for money. He could not have eaten gold coins. Neither would Crusoe and Friday, perhaps exchanging fish for lumber, need to bother about money. But when society expands beyond a few families, the stage is already set for the emergence of money.
To explain the role of money, we must go even further back, and ask: why do men exchange at all? Exchange is the prime basis of our economic life. Without exchanges, there would be no real economy and, practically, no society. Clearly, a voluntary exchange occurs because both parties expect to benefit. An exchange is an agreement between A and B to transfer the goods or services of one man for the goods and services of the other. Obviously, both benefit because each values what he receives in exchange more than what he gives up. When Crusoe, say, exchanges some fish for lumber, he values the lumber he "buys" more than the fish he "sells," while Friday, on the contrary, values the fish more than the lumber. From Aristotle to Marx, men have mistakenly believed that an exchange records some sort of equality of value—that if one barrel of fish is exchanged for ten logs, there is some sort of underlying equality between them. Actually, the exchange was made only because each party valued the two products in different order.
Why should exchange be so universal among mankind? Fundamentally, because of the great variety in nature: the variety in man, and the diversity of location of natural resources. Every man has a different set of skills and aptitudes, and every plot of ground has its own unique features, its own distinctive resources. From this external natural fact of variety come exchanges; wheat in Kansas for iron in Minnesota; one man's medical services for another's playing of the violin. Specialization permits each man to develop his best skill, and allows each region to develop its own particular resources. If no one could exchange, if every man were forced to be completely self-sufficient, it is obvious that most of us would starve to death, and the rest would barely remain alive. Exchange is the lifeblood, not only of our economy, but of civilization itself.