Alterations in real prices occur slowly as a rule. But this stability of prices has its cause in the stability of the price-determinants, not in the Law of Price-determination itself. Prices change slowly because the subjective valuations of human beings change slowly. Human needs, and human opinions as to the suitability of goods for satisfying those needs, are no more liable to frequent and sudden changes than are the stocks of goods available for consumption, or the manner of their social distribution;

The Theory of Money and Credit