Clearly the chief characteristic which any commodity must enjoy, if it is to become a medium of exchange, is use value; that is, society as a whole must value it highly enough to desire to possess it for its own worth and not because some individual or some government has said that it possesses value. Since it has value it will have acceptability - that is, it will be desired by the individual members of society. If the members of any social group prefer cattle, for example, to all other forms of wealth, then cattle, other things being equal, naturally become the medium of exchange.

Notice that the last statement in the preceding paragraph bears the qualification, "other things being equal." Cattle might have a wider acceptability than furs, and yet, on account of their small value compared to their large bulk, be less desirable as a money. Diamonds, on the other hand, might also be the most highly and the most widely desired commodity in existence without becoming a medium of exchange, simply because a diamond possesses too much value compared to its size. Also the value of the commodity which is to serve as money must be reasonably stable - that is, its value must not vary too widely or too quickly. We may conclude, therefore, that the value characteristics of a good money are three in number: (1) value, (2) reasonably large value in small bulk, and (3) stability of value.