This is an article on the great economist, Leland Yeager, who has just passed away. And in this article in memoriam, Market Grandmaster by James A. Dorn, there is a discussion on Say’s Law which is dangerously off centre as has been virtually every discussion since the publication of The General Theory in 1936. Here is what is right taken directly from the article: “there can be no problem of deficiency of aggregate demand”. That is precisely what Say’s Law means. To this principle there are no exceptions. But what is said is that “fundamentally” there can be no deficiency of demand, but that it does occur on some occasions. To accept an exception, especially this, you might as well be a Keynesian.

Say’s Law did not rule out recessions. The idea that classical economists had some principle that made recessions impossible is so loony it’s hard to understand how such an idea could ever have established itself, yet that is what Keynes did. Therefore, to refute Keynes, one must begin by showing how untrue this was. Say’s Law rules out only one thing. It rules out, and rules out absolutely, demand deficiency as a cause of recession but nothing else, and most especially recessions due to monetary disturbances which were recognised by classical economists as frequent and often devastating. The classical theory of the cycle, stretching back to the start of the nineteenth century, discussed monetary breakdown and their effects. Monetary disturbances are not a deficiency of demand but a structural deformation. The GFC was not caused by a deficiency of demand but a monetary disturbance. Nor did a public sector stimulus in any economy lead to recovery, which might have occurred had demand deficiency been the problem. The contour and causes of the GFC were not just consistent with the classical theory of recession, but so too was the failure of any recovery to gather momentum anywhere in the world. This description mis-states the conclusions reached by classical economists, which we now bundle together under the heading of Say’s Law.

When the supply of and demand for money do not mesh, monetary disequilibrium can upset the smooth operation of the market mechanism and Say’s Law must be qualified. This is especially true when price and resource adjustments are sluggish.

To describe this as a qualification to Say’s Law is simply wrong, but worse, concedes almost all the ground that Keynesians need to drive public spending upwards, and not just during recessions but in every phase of the cycle.

Here is Dorn’s text on Say’s Law.

Say’s Law Is Fundamentally Right

According to Yeager (1979), “There has been too much aggregation in macroeconomics, theoretical and applied—too much of the notion of aggregate demand confronting aggregate supply. Fundamentally, Say’s Law is right: supply of some goods and services constitutes demand for other goods and services; fundamentally there can be no problem of deficiency of aggregate demand.” However, “the exchange of goods and services against goods and services takes place through money.” When the supply of and demand for money do not mesh, monetary disequilibrium can upset
the smooth operation of the market mechanism and Say’s Law must be qualified. This is especially true when price and resource adjustments are sluggish.

Consequently, Yeager emphasized that students need “to understand the tremendous importance of money in facilitating exchange and thus in facilitating the division of labor in producing
the goods to be exchanged.” In particular, they need to recognize that “money facilitates economic calculation and the comparison of costs and benefits and the signaling function of price and
profit” (ibid.).

Yeager: Market Grandmaster

Yeager goes on to argue that it is “precisely because money is so important to the working of the economic system [that] monetary disorders can have fateful consequences.” Thus, there is a “hitch in Say’s Law: Although ‘fundamentally’ goods and services exchange against goods and services, money is the intermediary in this process; and if the demand for and supply of money get out of balance, these fundamental exchanges are impeded” (ibid.).

Yeager elaborated on this idea elsewhere, explaining that an

imbalance between the actual quantity of money and the total of desired cash balances cannot readily be forestalled or corrected through adjustment of the price of money on the market for money because money, in contrast with all other things, does not have a single price and single market of its own. Monetary imbalance has to be corrected through the roundabout and sluggish process of adjusting the prices of a great many individual goods and services (and securities). Because prices do not immediately absorb the full impact of the supply and demand imbalances for individual goods and services that are the counterpart of an overall monetary imbalance, quantities traded and produced are affected also. Thus, the deflationary process associated with an excess demand for money, in particular, can be painful [Yeager 1983: 307].