Jean-Baptiste Say and “Say’s Law”

I take my cue from this interesting post by Gene Callahan (“Did Keynes Mischaracterize Say’s Law?,” September 12, 2012).

So how did Jean-Baptiste Say (1767–1832) actually define his “law of markets” (or “loi des débouchés,” in French)?

Note that I am not talking about how later Classical economists defined or formulated Say’s Law, and it is possible to argue that they did so better than Say himself ever did. Thomas Sowell (1994: 39–41) argues that, in Classical economics, Say’s law can be expressed by these propositions:

“(1) The total factor payments received for producing a given volume (or value) of output are necessarily sufficient to purchase that volume (or value) of output [an idea in James Mill].

(2) There is no loss of purchasing power anywhere in the economy. People save only to the extent of their desire to invest and do not hold money beyond their transactions need during the current period [James Mill and Adam Smith].

(3) Investment is only an internal transfer, not a net reduction, of aggregate demand. The same amount that could have been spent by the thrifty consumer will be spent by the capitalists and/or the workers in the investment goods sector [John Stuart Mill].

(4) In real terms, supply equals demand ex ante [= “before the event”], since each individual produces only because of, and to the extent of, his demand for other goods. (Sometimes this doctrine was supported by demonstrating that supply equals demand ex post.) [James Mill.]

(5) A higher rate of savings will cause a higher rate of subsequent growth in aggregate output [James Mill and Adam Smith].

(6) Disequilibrium in the economy can exist only because the internal proportions of output differ from consumer’s preferred mix—not because output is excessive in the aggregate” [Say, Ricardo, Torrens, James Mill] (Sowell 1994: 39–41).

So this is Say’s law, according to the Classical economists.
But one will search in vain for anything as explicit and clear as these ideas in the writings of Say himself.

The question of how Say defined what was later called Say’s Law is complex, because Say produced different versions of the “law of markets” in different works, and even in different editions of the same work.

One can find the following versions of the law:

(1) in the first edition of Say’s Traité d’économie politique (1803; or the Treatise on Political Economy in English), where the “law of markets” is not completely or properly formulated;

(2) in the second edition of Traité d’économie politique/Treatise on Political Economy (published in 1814) where we have a revised version of Say’s law in its recognisable form (Baumol 1977: 147). It is unclear to me whether Say revised this even further in the 3rd edition (1817), 4th (1819), and 5th edition (1826) of the Treatise. The 6th edition, with Say’s final corrections, was edited by his son Horace Émile Say in 1846.

(3) a summary in Say’s Catechism of Political Economy (1816: 103–105).

So when anyone talks about how Jean-Baptiste Say defined Say’s law, one must ask: in what work and when?

For English speaking people, I suspect the most accessible version is the English translation of the 4th edition by C. R. Prinsep and C. C. Biddle called A Treatise on Political Economy, or, The Production, Distribution, and Consumption of Wealth (Wells and Lilly, Boston, 1821).

The relevant part of text is as follows (with yellow highlighting of important passages):

Chapter XV
Of the Vent or Demand for Products

It is common to hear adventurers in the different channels of industry assert, that their difficulty lies not in the production, but in the disposal of commodities; that products would always be abundant, if there were but a ready demand, or market for them. When the demand for their commodities is slow, difficult, and productive of little advantage, they pronounce money to be scarce; the grand object of their desire is, a consumption brisk enough to quicken sales and keep up prices. But ask them what peculiar causes and circumstances facilitate the demand for their products, and you will soon perceive that most of them have extremely vague notions of these matters; that their observation of facts is imperfect, and their explanation still more so; that they treat doubtful points as matter of certainty, often pray for what is directly opposite to their interests, and importunately solicit from authority a protection of the most mischievous tendency.

To enable us to form clear and correct practical notions in regard to markets for the products of industry, we must carefully analyse the best established and most certain facts, and apply to them the inferences we have already deduced from a similar way of proceeding; and thus perhaps we may arrive at new and important truths, that may serve to enlighten the views of the agents of industry, and to give confidence to the measures of governments anxious to afford them encouragement.

A man who applies his labour to the investing of objects with value by the creation of utility of some sort, can not expect such a value to be appreciated and paid for, unless where other men have the means of purchasing it. Now, of what do these means consist? Of other values of other products, likewise the fruits of industry, capital, and land. Which leads us to a conclusion that may at first sight appear paradoxical, namely, that it is production which opens a demand for products.

Should a tradesman say, “I do not want other products for my woollens, I want money,” there could be little difficulty in convincing him that his customers could not pay him in money, without having first procured it by the sale of some other commodities of their own. “Yonder farmer,” he may be told, “will buy your woollens, if his crops be good, and will buy more or less according to their abundance or scantiness; he can buy none at all, if his crops fail altogether. Neither can you buy his wool nor his corn yourself, unless you contrive to get woollens or some other article to buy withal. You say, you only want money; I say, you want other commodities, and not money. For what, in point of fact, do you want the money? Is it not for the purchase of raw materials or stock for your trade, or victuals for your support? Wherefore, it is products that you want, and not money. The silver coin you will have received on the sale of your own products, and given in the purchase of those of other people, will the next moment execute the same office between other contracting parties, and so from one to another to infinity; just as a public vehicle successively transports objects one after another. If you can not find a ready sale for your commodity, will you say, it is merely for want of a vehicle to transport it? For, after all, money is but the agent of the transfer of values. Its whole utility has consisted in conveying to your hands the value of the commodities, which your customer has sold, for the purpose of buying again from you; and the very next purchase you make, it will again convey to a third person the value of the products you may have sold to others. So that you will have bought, and every body must buy, the objects of want or desire, each with the value of his respective products transformed into money for the moment only. Otherwise, how could it be possible that there should now be bought and sold in France five or six times as many commodities, as in the miserable reign of Charles VI? Is it not obvious, that five or six times as many commodities must have been produced, and that they must have served to purchase one or the other?”

Thus, to say that sales are dull, owing to the scarcity of money, is to mistake the means for the cause; an error that proceeds from the circumstance, that almost all produce is in the first instance exchanged for money, before it is ultimately converted into other produce: and the commodity, which recurs so repeatedly in use, appears to vulgar apprehensions the most important of commodities, and the end and object of all transactions, whereas it is only the medium. Sales cannot be said to be dull because money is scarce, but because other products are so. There is always money enough to conduct the circulation and mutual interchange of other values, when those values really exist. Should the increase of traffic require more money to facilitate it, the want is easily supplied, and is a strong indication of prosperity a proof that a great abundance of values has been created, which it is wished to exchange for other values. In such cases, merchants know well enough how to find substitutes for the product serving as the medium of exchange or money*; and money itself soon pours in, for this reason, that all produce naturally gravitates to that place where it is most in demand. It is a good sign when the business is too great for the money; just in the same way as it is a good sign when the goods are too plentiful for the warehouses.

* By bills at sight or after date, bank-notes, running credits, write-offs, &c. as at London and Amsterdam.

When a superabundant article can find no vent, the scarcity of money has so little to do with the obstruction of its sale, that the sellers would gladly receive its value in goods for their own consumption at the current price of the day: they would not ask for money, or have any occasion for that product, since the only use they could make of it would be to convert it forthwith into articles of their own consumption.

This observation is applicable to all cases, where there is a supply of commodities or of services in the market. They will universally find the most extensive demand in those places, where the most of values are produced; because in no other places are the sole means of purchase created, that is, values. Money performs but a momentary function in this double exchange; and when the transaction is finally closed, it will always be found, that one kind of commodity has been exchanged for another.

It is worth while to remark, that a product is no sooner created, than it, from that instant, affords a market for other products to the full extent of its own value. When the producer has put the finishing hand to his product, he is most anxious to sell it immediately, lest its value should diminish in his hands. Nor is he less anxious to dispose of the money he may get for it; for the value of money is also perishable. But the only way of getting rid of money is in the purchase of some product or other. Thus, the mere circumstance of the creation of one product immediately opens a vent for other products.

For this reason, a good harvest is favourable, not only to the agriculturist, but likewise to the dealers in all commodities generally. The greater the crop, the larger are the purchases of the growers. A bad harvest, on the contrary, hurts the sale of commodities at large. And so it is also with the products of manufacture and commerce. The success of one branch of commerce supplies more ample means of purchase, and consequently opens a market for the products of all the other branches; on the other hand, the stagnation of one channel of manufacture, or of commerce, is felt in all the rest.

But it may be asked, if this be so, how does it happen, that there is at times so great a glut of commodities in the market, and so much difficulty in finding a vent for them? Why cannot one of these superabundant commodities be exchanged for another? I answer that the glut of a particular commodity arises from its having outrun the total demand for it in one or two ways; either because it has been produced in excessive abundance, or because the production of other commodities has fallen short.

It is because the production of some commodities has declined, that other commodities are superabundant. To use a more hackneyed phrase, people have bought less, because they have made less profit; and they have made less profit for one or two causes; either they have found difficulties in the employment of their productive means, or these means have themselves been deficient.

It is observable, moreover, that precisely at the same time that one commodity makes a loss, another commodity is making excessive profit. And, since such profits must operate as a powerful stimulus to the cultivation of that particular kind of products, there must needs be some violent means, or some extraordinary cause, a political or natural convulsion, or the avarice or ignorance of authority, to perpetuate this scarcity on the one hand, and consequent glut on the other. No sooner is the cause of this political disease removed, than the means of production feel a natural impulse towards the vacant channels, the replenishment of which restores activity to all the others. One kind of production would seldom outstrip every other, and its products be disproportionately cheapened, were production left entirely free.

Should a producer imagine, that many other classes, yielding no material products, are his customers and consumers equally with the classes that raise themselves a product of their own; as, for example, public functionaries, physicians, lawyers, churchmen, &c., and thence infer, that there is a class of demand other than that of the actual producers, he would but expose the shallowness and superficiality of his ideas. A priest goes to a shop to buy a gown or a surplice; he takes the value, that is to make the purchase, in the form of money. Whence had he that money? From some tax-gatherer who has taken it from a tax-payer. But whence did this latter derive it? From the value he has himself produced. This value, first produced by the tax-payer, and afterwards turned into money, and given to the priest for his salary, has enabled him to make the purchase. The priest stands in the place of the producer, who might himself have laid the value of his product on his own account, in the purchase, perhaps, not of a gown or surplice, but of some other more serviceable product. The consumption of the particular product, the gown or surplice, has but supplanted that of some other product. It is quite impossible that the purchase of one product can be affected, otherwise than by the value of another.

From this important truth may be deduced the following important conclusions: —

1. That, in every community the more numerous are the producers, and the more various their productions, the more prompt, numerous, and extensive are the markets for those productions; and, by a natural consequence, the more profitable are they to the producers; for price rises with the demand. But this advantage is to be derived from real production alone, and not from a forced circulation of products; for a value once created is not augmented in its passage from one hand to another, nor by being seized and expended by the government, instead of by an individual. The man, that lives upon the productions of other people, originates no demand for those productions; he merely puts himself in the place of the producer, to the great injury of production, as we shall presently see.

2. That each individual is interested in the general prosperity of all, and that the success of one branch of industry promotes that of all the others. In fact, whatever profession or line of business a man may devote himself to, he is the better paid and the more readily finds employment, in proportion as he sees others thriving equally around him. A man of talent, that scarcely vegetates in a retrograde state of society, would find a thousand ways of turning his faculties to account in a thriving community that could afford to employ and reward his ability. A merchant established in a rich and populous town, sells to a much larger amount than one who sets up in a poor district, with a population sunk in indolence and apathy.

What could an active manufacturer, or an intelligent merchant, do in a small deserted and semi-barbarous town in a remote corner of Poland or Westphalia? Though in no fear of a competitor, he could sell but little, because little was produced; whilst at Paris, Amsterdam, or London, in spite of the competition of a hundred dealers in his own line, he might do business on the largest scale. The reason is obvious: he is surrounded with people who produce largely in an infinity of ways, and who make purchases, each with his respective products, that is to say, with the money arising from the sale of what he may have produced.

This is the true source of the gains made by the towns’ people out of the country people, and again by the latter out of the former; both of them have wherewith to buy more largely, the more amply they themselves produce. A city, standing in the centre of a rich surrounding country, feels no want of rich and numerous customers’ and, on the other hand, the vicinity of an opulent city gives additional value to the produce of the country. The division of nations into agricultural, manufacturing, and commercial, is idle enough. For the success of a people in agriculture is a stimulus to its manufacturing and commercial prosperity; and the flourishing condition of its manufacture and commerce reflects a benefit upon its agriculture also.

The position of a nation, in respect of its neighbours, is analogous to the relation of one of its provinces to the others, or of the country to the town; it has an interest in their prosperity, being sure to profit by their opulence. The government of the United States, therefore, acted most wisely, in their attempt, about the year 1802, to civilize their savage neighbours, the Creek Indians. The design was to introduce habits of industry amongst them, and make them producers capable of carrying on a barter trade with the States of the Union; for there is nothing to be got by dealing with a people that have nothing to pay. It is useful and honourable to mankind, that one nation among so many should conduct itself uniformly upon liberal principles. The brilliant results of this enlightened policy will demonstrate, that the systems and theories really destructive and fallacious, are the exclusive and jealous maxims acted upon by the old European governments, and by them most impudently styled practical truths, for no other reason, as it would seem, than because they have the misfortune to put them in practice. The United States will have the honour of proving experimentally, that true policy goes hand in hand with moderation and humanity.

3. From this fruitful principle, we may draw this further conclusion, that it is no injury to the internal or national industry and production to buy and import commodities from abroad; for nothing can be bought from strangers, except with native products, which find a vent in this external traffic. Should it be objected, that this foreign produce may have been bought with specie, I answer, specie is not always a native product, but must have been bought itself with the products of native industry; so that, whether the foreign articles be paid for in specie or in home products, the vent for national industry is the same in both cases.

4. The same principle leads to the conclusion, that the encouragement of mere consumption is no benefit to commerce; for the difficulty lies in supplying the means, not in stimulating the desire of consumption; and we have seen that production alone, furnishes those means. Thus, it is the aim of good government to stimulate production, of bad government to encourage consumption.

For the same reason that the creation of a new product is the opening of a new market for other products, the consumption or destruction of a product is the stoppage of a vent for them. This is no evil where the end of the product has been answered, by its destruction, which end is the satisfying of some human want, or the creation of some new product designed for such a satisfaction. Indeed, if the nation be in a thriving condition, the gross national re-production exceeds the gross consumption. The consumed products have fulfilled their office, as it is natural and fitting they should; the consumption, however, has opened no new market, but just the reverse.

Having once arrived at the clear conviction, that the general demand for products is brisk in proportion to the activity of production, we need not trouble ourselves much to inquire towards what channel of industry production may be most advantageously directed. The products created give rise to various degrees of demand, according to the wants, the manners, the comparative capital, industry, and natural resources of each country; the article most in request, owing to the competition of buyers, yields the best interest of money to the capitalist, the largest profits to the adventurer, and the best wages to the labourer; and the agency of their respective services is naturally attracted by these advantages towards those particular channels.

In a community, city, province, or nation, that produces abundantly, and adds every moment to the sum of its products, almost all the branches of commerce, manufacture, and generally of industry, yield handsome profits, because the demand is great, and because there is always a large quantity of products in the market, ready to bid for new productive services. And, vice versa, wherever, by reason of the blunders of the nation or its government, production is stationary, or does not keep pace with consumption, the demand gradually declines, the value of the product is less than the charges of its production; no productive exertion is properly rewarded; profits and wages decrease; the employment of capital becomes less advantageous and more hazardous; it is consumed piecemeal, not through extravagance, but through necessity, and because the sources of profit are dried up. The labouring classes experience a want of work; families before in tolerable circumstances, are more cramped and confined; and those before in difficulties are left altogether destitute. Depopulation, misery, and returning barbarism, occupy the place of abundance and happiness. Such are the concomitants of declining production, which are only to be remedied by frugality, intelligence, activity, and freedom. (Say 1821: 107–119).

We could sum up the fundamental principles of this chapter as follows:

(1) that the “origin of the means” of purchasing products is the value of other products: “production ... opens a demand for products.” The means to attain the money for purchasing products comes from “having first procured it by the sale of some other commodities.”

(2) that producers do not really want money, but other goods. Therefore Say analyses a capitalist economy in terms of barter transactions, by which the money is merely a “veil.”

(3) money is merely used to purchase more commodities:

“The silver coin you will have received on the sale of your own products, and given in the purchase of those of other people, will the next moment execute the same office between other contracting parties, and so from one to another to infinity.”

(4) that the production and sale of a product creates demand for other products:

“It is worth while to remark, that a product is no sooner created, than it, from that instant, affords a market for other products to the full extent of its own value. When the producer has put the finishing hand to his product, he is most anxious to sell it immediately, lest its value should diminish in his hands. Nor is he less anxious to dispose of the money he may get for it; for the value of money is also perishable. But the only way of getting rid of money is in the purchase of some product or other. Thus, the mere circumstance of the creation of one product immediately opens a vent for other products.”

It is particularly important to note the last sentence:

“Thus, the mere circumstance of the creation of one product immediately opens a vent for other products.”

By “vent” we can understand “demand”: so Say here is expressing the idea that the mere production of a commodity opens demand for other products.

Thus the sentence “supply creates its own demand” appears to be a legitimate way of expressing this idea.

For Baumol (1977: 158–159), this passage also demonstrates that Say had formulated and expressed a version of “Say’s Equality,” one of the two versions of Say’s law. According to Baumol, Say’s equality:

“admits the possibility of (brief) periods of disequilibrium during which the total demand for goods may fall short of the total supply, but maintains that there exist reliable equilibrating forces that must soon bring the two together.” (Baumol 1977: 146).

So what is wrong with the ideas described above?

It is easy to see why and how Say was in error:

(1) Say’s analysis ignores the role of endogenous money and the way in which capitalist banking systems and businesses create new money by debt instruments: whether bills of exchange, promissory notes, cheques, or fractional reserve bank notes.

The origin of the “means of purchasing” many commodities is not production, but debt, or new money created by the credit/debt operations of fractional reserve banks, and even things as simple as negotiable bills of exchange and other negotiable debt instruments.

(2) There is a flaw in Say’s analysis: the diversion of money into purchasing of financial assets and real assets on secondary markets, for speculative purposes. That becomes a major kind of spending for those of extreme wealth.

The money used to buy such assets can then flow to other speculators, who buy new financial assets or hold money idle in the process of using it in further speculation on assets. Thus there is a “speculative demand” for money that can rise or fall.

Money can be (1) held idle, (2) used to buy commodities or (3) used to buy assets (whether real or financial) on secondary markets.

(3) Say subscribed to the view that money cannot provide direct utility:

“For, after all, money is but the agent of the transfer of values. Its whole utility has consisted in conveying to your hands the value of the commodities, which your customer has sold, for the purpose of buying again from you; and the very next purchase you make, it will again convey to a third person the value of the products you may have sold to others.”

This is made clear to us by Say’s statement: “[sc. the] whole utility [sc. of money] has consisted in conveying to your hands the value of the commodities.” This is a world where nobody holds money for significant periods of time because money can have no utility, except in what it can purchase in terms of commodities.

But that is not the world we live in. We live in a world of uncertainty. In the face of uncertainty, money can yield direct utility (Graziani 2003: 11):

“In an uncertain world, the possession of money and other nonproducible liquid assets provides utility by protecting the holder from fear of being unable to meet future liabilities” (Davidson 2003: 236).

Possession of money gives direct satisfaction or utility in providing protection against uncertainty, and gives us the satisfaction or feeling of assurance that we will be able to discharge expected and unexpected future liabilities or obligations.

Appendix: The Law of Markets in Say’s Catechism of Political Economy

I reproduce below the relevant section of Say’s Catechism of Political Economy (1816) where he discusses the law of markets:

CHAPTER XX.
On Markets.

What do you mean by markets?

Before answering this question, I beg you to remark, that those who engage in production are seldom occupied with more than one product, or at most a small number of products. A tanner produces nothing but leather; a clothier, cloth; one merchant deals in wine, another imports foreign goods; one cultivator raises the vine, another corn, a third cattle.

What consequences do you draw from that?

That none of them can enjoy the greatest part of the various articles for which he has occasion, except by means of exchanging the greater part of his own productions for those which he desires to consume: so that the greater part of the consumptions of society take place only in consequence of an exchange.

But when we are able easily to exchange our own productions for those which we want, we are said to have found ready markets for our products.

On what does the ready sale of any particular article depend?

On the vivacity of the demand for it.

On what does the vivacity of the demand depend?

On two motives, which are—1st. The utility of the product, that is, the necessity the consumer has for it:—2d. The quantity of other products he is able to give in exchange.

I conceive the first motive. As to the second, it appears to me that it is the quantity of money that the buyer possesses, which induces him to buy or not.

That is also true: but the quantity of money which he has, depends on the quantity of product with which he has been able to buy this money.

Could he not obtain the money otherwise, than by having acquired it by products?

No.

If he had received the money from his tenants ... .?

His tenant had received it from the sale of part of the products to which the earth had contributed.

If he had received the interest of a capital lent — ?

The undertaker who employed that capital had received the money which he paid, on the sale of a part of the products to which his capital had concurred.

If the purchaser had obtained this money by gift or inheritance — ?

The giver, or he from whom the giver had obtained it, had it in exchange for some product.

In every case the money, with which any product is purchased, must have been produced by the sale of another product; and the purchase may be considered as an exchange in which the purchaser gives that which he has produced, (or that which another has produced for him), and in which he receives the thing bought.

What do you conclude from this?

That the more the purchasers produce, the more they have to purchase with, and that the productions of the one procure purchasers to the other.

It appears to me, that if the buyers only purchased by means of their products, they have generally more products than money to offer in payment.

Every producer asks for money in exchange for his products, only for the purpose of employing that money again immediately in the purchase of another product; for we do not consume money, and it is not sought after in ordinary cases to conceal it: thus, when a producer desires to exchange his product for money, he may be considered as already asking for the merchandise which he proposes to buy with this money. It is thus that the producers, though they have all of them the air of demanding money for their goods, do in reality demand merchandise for their merchandise.

Then the more merchandise there is produced, the more animated is the demand for merchandise?

Without doubt. It is for this reason that countries, which are but little civilized, present few markets, and those for products but little varied; while in populous, industrious, and productive districts, the sales are repeated and considerable.

It is not necessary then, in order that markets should he extended and multiplied, to look for them in foreign countries?

No; it is sufficient that other products should be multiplied in our own country.

What is it that multiplies foreign markets?

The riches of neighbouring nations, and the activity of their production.

What consequence do you draw from that?

That each of them is interested in the prosperity of his neighbour, and every nation in the prosperity of all others: for it is only those who produce much that can readily give you any thing in exchange for your products: or which comes to the same thing, that can give you the value of them in money.

What other consequence follows from this?

That riches are not exclusive: that, so far from that which another man, or another people gains, being a loss to you, their gains are favourable to you; that it is only necessary for you to produce, not that which they produce easier than you, but that which they cannot fail to demand from you by means of their products; and that wars, entered into for commerce, will appear so much the more senseless as we become better informed. (Say 1816: 102–106).

BIBLIOGRAPHY

Davidson, P. 2003. “Keynes’ General Theory,” in J. E. King (ed.), Elgar Companion to Post Keynesian Economics. Edward Elgar Publishing, Cheltenham, UK and Northampton, MA. 229–237.

Graziani, A. 2003. The Monetary Theory of Production. Cambridge University Press, Cambridge.

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