A fundamental tenet of classical economics, sometimes called the fundamental law of markets, and associated with the French economist Jean-Baptiste Say (1767–1832). It has various formulations, all pointing to the idea that since goods and services are paid for with goods and services, then in general demand matches supply. This is taken to imply that although as demand shifts from one product to another there can be overproduction of the particular goods that are no longer in demand, nevertheless there can be no overall glut in an economy. In other words because a product in effect constitutes a demand for whatever the supplier is destined to acquire, it makes no sense to talk of an overall shortage of demand. The view was one principal target of Keynes, who considered that Say’s law forgot the role of money as a hedge or store of value, something that can be hoarded as a credit or abstract claim to future goods or services. It thus misunderstood the way demand dries up during recessions. But in one sense Say’s law still holds: if a supplier holds on to the money he receives instead of reinvesting it, then he has demanded money, instead of what it might purchase. However, money hoarded is little help in curing chronic unemployment, which was Keynes’s concern. See also animal spirits, risk.