Underconsumption

In underconsumption theory in economics, recessions and stagnation arise due to inadequate consumer demand relative to the amount produced. The theory formed the basis for the development of Keynesian economics and the theory of aggregate demand after the 1930s.

Underconsumption theory narrowly refers to heterodox economists in Britain in the 19th century, particularly 1815 onwards, who advanced the theory of underconsumption and rejected classical economics in the form of Ricardian economics. These economists did not form a unified school, and their theories were rejected by mainstream economics of the time.

Underconsumption is an old concept in economics, going back to the 1598 French mercantilist text Les Trésors et richesses pour mettre l'Estat en Splendeur (The Treasures and riches to put the State in Splendor) by Barthélemy de Laffemas, if not earlier. The concept of underconsumption had been used repeatedly as part of the criticism of Say's Law until underconsumption theory was largely replaced by Keynesian economics which points to a more complete explanation of the failure of aggregate demand to attain potential output, i.e., the level of production corresponding to full employment.

One of the early underconsumption theories says that because workers are paid a wage less than they produce, they cannot buy back as much as they produce. Thus, there will always be inadequate demand for the product. This, of course, ignores other sources of demand, to which we return below.

In his book Underconsumption Theories (International Publishers, 1976) Michael Bleaney defined two main elements of classical (pre-Keynesian) underconsumption theory. First, the only source of recessions, stagnation, and other aggregate demand failures was inadequate consumer demand. Second, a capitalist economy tends toward a state of persistent depression because of this. Thus, underconsumption is not seen as part of business cycles as much as (perhaps) the general economic environment in which they occur. Compare to the tendency of the rate of profit to fall, which has a similar belief in stagnation as the natural (stable) state, but which is otherwise distinct and in critical opposition to underconsumption theory.

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