Minsky on the Non-Neutrality of Money

I try not to spend too much time criticizing orthodox economics. I think that heterodox people who spend all their energy pointing out the shortcomings and contradictions of the mainstream are, in a sense, making the same mistake as the ones who spend all their energy trying to make their ideas acceptable to the mainstream. We should focus on building up our positive knowledge of social reality, and let the profession fend for itself.

That said, like almost everyone in the world of heterodoxy I do end up writing a lot, and often obstreperously, about what is wrong with the economics profession. To which you can fairly respond: OK, but where is the alternative economics you’re proposing instead?

The honest answer is, it doesn’t exist. There are many heterodox economics, including a large contingent of Post Keynesians, but Post Keynesianism is not a coherent alternative research program. [1] Still, there are lots of promising pieces, which might someday be assembled into a coherent program. One of these is labeled “Minsky”. [2] Unfortunately, while Minsky is certainly known to a broader audience than most economists associated with heterodoxy, it’s mainly only for the financial fragility hypothesis, which I would argue is not central to his contribution.

I recently read a short piece he wrote in 1993, towards the end of his career, that gives an excellent overview of his approach. It’s what I’d recommend — along with the overview of his work by Perry Mehrling that I mentioned in the earlier post, and also the overview by Pollin and Dymski — as a starting point for anyone interested in his work.

* * *

“The Non-Neutrality of Money” covers the whole field of Minsky’s interests and can be read as a kind of summing-up of his mature thought. So it’s interesting that he gave it that title. Admittedly it partly reflects the particular context it was written in, but it also, I think, reflects how critical the neutrality or otherwise of money is in defining alternative visions of what an economy is.

Minsky starts out with a description of what he takes to be the conceptual framework of orthodox economics, represented here by Ben Bernanke’s “Credit in the Macroeconomy“:

The dominant paradigm is an equilibrium construct in which initial endowments of agents, preference systems and production relations, along with maximizing behavior, determine relative prices, outputs and allocation… Money and financial interrelations are not relevant to the determination of these equilibrium values … “real” factors determine “real” variables.

Some people take this construct literally. This leads to Real Business Cycles and claims that monetary policy has never had any effects. Minsky sees no point in even criticizing that approach. The alternative, which he does criticize, is to postulate some additional “frictions” that prevent the long-run equilibrium from being realized, at least right away. Often, as in the Bernanke piece, the frictions take the form of information asymmetries that prevent some mutually beneficial transactions — loans to borrowers without collateral, say — from taking place. But, Minsky says, there is a contradiction here.

On the one hand, perfect foresight is assumed … to demonstrate the existence of equilibrium, and on the other hand, imperfect foresight is assumed … to generate the existence of an underemployment equilibrium and the possibility of policy effectiveness.

Once we have admitted that money and money contracts are necessary to economic activity, and not just an arbitrary numeraire, it no longer makes sense to make simulating a world without money as the goal of policy. If money is useful, isn’t it better to have more of it, and worse to have less, or none? [3] The information-asymmetry version of this problem is actually just the latest iteration of a very old puzzle that goes back to Adam Smith, or even earlier. Smith and the other Classical economists were unanimous that the best monetary system was one that guaranteed a “perfect” circulation, by which they meant, the quantity of money that would circulate if metallic currency were used exclusively. But this posed two obvious questions: First, how could you know how much metallic currency would circulate in that counterfactual world, and exactly which forms of “money” in the real world should you compare to that hypothetical amount? And second, if the ideal monetary system was one in which the quantity of money came closest to what it would be if only metal coins were used, why did people — in the most prosperous countries especially — go to such lengths to develop forms of payment other than metallic coins? Hume, in the 18th century, could still hew to the logic of theory and and conclude that, actually, paper money, bills of exchange, banks that functioned as anything but safety-deposit boxes [4] and all the rest of the modern financial system was a big mistake. For later writers, for obvious reasons, this wasn’t a credible position, and so the problem tended to be evaded rather than addressed head on.

Or to come back to the specific way Minsky presents the problem. Suppose I have some productive project available to me but lack sufficient claim on society’s resources to carry it out. In principle, I could get them by pledging a fraction of the results of my project. But that might not work, perhaps because the results are too far in the future, or too uncertain, or — information asymmetry — I have no way of sharing the knowledge that the project is viable or credibly committing to share its fruits. In that case “welfare” will be lower than it the hypothetical perfect-information alternative, and, given some additional assumptions, we will see something that looks like unemployment. Now, perhaps the monetary authority can in some way arrange for deferred or uncertain claims to be accepted more readily. That may result in resources becoming available for my project, potentially solving the unemployment problem. But, given the assumptions that created the need for policy in the first place, there is no reason to think that the projects funded as a result of this intervention wil be exactly the same as in the perfect-information case. And there is no reason to think there are not lots of other unrealized projects whose non-undertaking happens not to show up as unemployment. [5]

Returning to Minsky: A system of markets

is not the only way that economic interrelations can be modeled. Every capitalist economy can be described in terms of interrelated balance sheets … The entries on balance sheets can be read as payment commitments (liabilities) and expected payment receipts (assets), both denominated in a common unit.

We don’t have to see an endowments of goods, tastes for consumption, and a given technology for converting the endowments to consumption goods as the atomic units of the economy. We can instead start with a set of money flows between units, and the capitalized expectations of future money flows captured on balance sheets. In the former perspective, money payments and commitments are a secondary complication that we may want to introduce for specific problems. In the latter, Minskyan perspective, exchanges of goods are just one of the various forms of money flows between economic units.

Minsky continues:

In this structure, the real and the financial dimensions of the economy are not separated. There is no “real economy” whose behavior can be studied by abstracting from financial considerations. … In this model, money is never neutral.

The point here, again, is that real economies require people to make commitments today on the basis of expectations extending far into an uncertain future. Money and credit are tools to allow these commitments to be made. The more available are money and credit, the further into the future can be deferred the results that will justify today’s activity. If we can define a level of activity that we call full employment or price stability — and I think Keynes was much too sanguine on this point — then a good monetary authority may be able to regulate the flow of money or credit (depending on the policy instrument) to keep actual activity near that level. But there is no connection, logical or practical, between that state of the economy and a hypothetical economy without money or credit at all.

For Minsky, this fundamental point is captured in Keynes’ two-price model. The price level of current output and capital assets are determined by two independent logics and vary independently. This is another way of saying that the classical dichotomy between relative prices and the overall price level, does not apply in a modern economy with a financial system and long-lived capital goods. Changes in the “supply of money,” whatever that means in practice, always affect the prices of assets relative to current output.

The price level of assets is determined by the relative value that units place on income in the future and liquidity now. …  

The price level of current output is determined by the labor costs and the markup per unit of output. … The aggregate markup for consumption goods is determined by the ratio of the wage bill in investment goods, the government deficit… , and the international trade balance, to the wage bill in the production of consumption goods. In this construct the competition of interest is between firms for profits.

Here we see Minsky’s Kaleckian side, which doesn’t get talked about much. Minsky was convinced that investment always determined profits, never the other way round. Specifically, he followed Kalecki in treating the accounting identity that “the capitalists get what they spend” as causal. That is, total profits are determined as total investment spending plus consumption by capitalists (plus the government deficit and trade surplus.)

Coming back to the question at hand, the critical point is that liquidity (or “money”) will affect these two prices differently. Think of it this way: If money is scarce, it will be costly to hold a large stock of it. So you will want to avoid committing yourself to fixed money payments in the future, you will prefer assets that can be easily converted into money as needed, and you will place a lower value on money income that is variable or uncertain. For all these reasons, long-lived capital goods will have a lower relative price in a liquidity-scare world than in a liquidity-abundant one. Or as Minsky puts it:

The non-neutrality of money … is due to the difference in the way money enters into the determination of the price level of capital assets and of current output. … the non-neutrality theorem reflects essential aspects of capitalism in that it recognizes that … assets exist and that they not only yield income streams but can also be sold or pledged.

Finally, we get to Minsky’s famous threefold classification of financial positions as hedge, speculative or Ponzi. In context, it’s clear that this was a secondary not a central concern. Minsky was not interested in finance for its own sake, but rather in understanding modern capitalist economies through the lens of finance. And it was certainly not Minsky’s intention for these terms to imply a judgement about more and less responsible financing practices. As he writes, “speculative” financing does not necessarily involve anything we would normally call speculation:

Speculative financing covers all financing that involves refinancing at market terms … Banks are always involved in speculative financing. The floating debt of companies and governments are speculative financing.

As for Ponzi finance, he admits this memorable label was a bad choice:

I would have been better served if I had labeled the situation “the capitalization of interest.” … Note that construction finance is almost always a prearranged Ponzi financing scheme. [6]

For me, the fundamental points here are (1) That our overarching vision of capitalist economies needs to be a system of “units” (including firms, governments, etc.) linked by current money payments and commitments to future money payments, not a set of agents exchanging goods; and (2) that the critical influence of liquidity comes in the terms on which long-lived commitments to particular forms of production trade off against current income.

[1] Marxism does, arguably, offer a coherent alternative — the only one at this point, I think. Anwar Shaikh recently wrote a nice piece, which I can’t locate at the moment, contrasting the Marxist-classical and Post Keynesian  strands of heterodoxy.

[2] In fact, as Perry Mehrling demonstrates in The Money Interest and the Public Interest, Minsky represents an older and largely forgotten tradition of American monetary economics, which owes relatively little to Keynes.

[3] Walras, Wicksell and many others dismiss the idea that more money can be beneficial by focusing on its function as a unit of account. You can’t consistently arrive earlier, they point out, by adjusting your watch, even if you might trick yourself the first few times. You can’t get taller by redefining the inch. Etc. But this overlooks the fact that people do actually hold money, and pay real costs to acquire  it.

[4] “The dearness of every thing, from plenty of money, is a disadvantage … This has made me entertain a doubt concerning the benefit of banks and paper-credit, which are so generally esteemed advantageous … to endeavour artificially to encrease such a credit, can never be the interest of any trading nation; but must lay them under disadvantages, by encreasing money beyond its natural proportion to labour and commodities… And in this view, it must be allowed, that no bank could be more advantageous, than such a one as locked up all the money it received, and never augmented the circulating coin, as is usual, by returning part of its treasure into commerce.” Political Discourses, 1752.

[5] This leads into Verdoorn’s law and anti-hysteresis, a topic I hope to return to.

[6] Daniel Davies should appreciate this.

Liquidity Preference on the F Line

Sitting on the subway today, I was struck by the fact that the three ads immediately opposite me were all for what you might call liquidity services. On the left was an ad for “personal asset loans” from something called Borro: “With this necklace … I funded my first business,” says a satisfied customer. Next to it was an MTA ad trumpeting the fact that you can pay your fare with a credit card. And then one from AptDeco.com, which I guess is a clearinghouse for used furniture sales, with the tagline “NYC is now your furniture store.”

the Borro ad was the next one to the left

This was interesting to me because I’ve just been thinking about the neutrality of money, and what an incoherent and contradictory idea it is.

The orthodox view is that the level of “real” economic activity is determined by “real” factors — endowments, tastes, technology — and people simply hold money balances proportionate to this level of activity. In this view, a change in the money supply can’t make anyone better or worse off, at least in the long run, or change anything about the economy except the price level.

Just looking at these ads shows us why that can’t be true. First of all, the question of what constitutes money. All three of these ads are, in effect, inviting you to use something as money that you couldn’t previously. Without the specialized intermediary services being hawked here, you couldn’t pay the startup costs of a business with a necklace (what’s this thing made of, plutonium?), or pay for a subway ride with a promise to pay later, or pay for much of anything with a used couch. And this new liquidity has real benefits — otherwise, no one would be buying it, and it wouldn’t be worth the cost of producing (or advertising) it. The idea — stated explicitly in the Borro ad — is that the liquidity they provide allows transactions to take place that otherwise wouldn’t. The ability to turn a piece of jewelry or a car into cash allows people to use productive capacities that otherwise would go to waste.

And of course this makes sense. The orthodox view is that money is useful — there must be a reason that we don’t live in a barter world, and more than that, that all this huge industry of liquidity provision exists. But money, for some reason, is not subject to the same kind of smoothly diminishing returns that other useful things are. There is a fixed amount you need, you can’t get by with less, and there’s no benefit at all in having more. The problem is worse than that, since the standard view is that money demand is strictly proportionate to the volume of transactions. But, which transactions? Presumably, the amount of economic activity depends on the availability of money — that’s what it means to say that money is useful. And furthermore, as these ads implicitly make clear, some transactions are more liquidity-intensive than others. No one is offering specialized intermediary services to help you buy a hamburger. So both the level and composition of economic activity must depend on money holdings. But in that case, you can’t say that money holdings depend only on the volume of activity — that would be circular. In a world where money is used at all, it can’t be neutral. An increase in the money supply (or better, in liquidity) may raise prices, but it won’t do so proportionately, since it also enables people to benefit from increasing their money holdings (or: shifting toward more liquid balance sheet positions) and to carry out liquidity-intensive transactions that were formerly unable to.

This is a very old issue in economics. The idea that money should be neutral is as old as the discipline, and so is this line of criticism of it. You can find both already in Hume. In “Of Money,” he lays out the argument that money must be neutral in the long run, since it is just an intrinsically meaningless unit of measure; real wealth depends on real resources, not on the units we count them in. Unlike most later writers, he follows this argument to its logical conclusion, that any resources devoted to liquidity provision are wasted:

This has made me entertain a doubt concerning the benefit of banks and paper-credit, which are so generally esteemed advantageous to every nation. That provisions and labour should become dear by the encrease of trade and money, is, in many respects, an inconvenience; but an inconvenience that is unavoidable, and the effect of that public wealth and prosperity which are the end of all our wishes. … But there appears no reason for encreasing that inconvenience by a counterfeit money, which foreigners will not accept of in any payment, and which any great disorder in the state will reduce to nothing. There are, it is true, many people in every rich state, who having large sums of money, would prefer paper with good security; as being of more easy transport and more safe custody. … And therefore it is better, it may be thought, that a public company should enjoy the benefit of that paper-credit, which always will have place in every opulent kingdom. But to endeavour artificially to encrease such a credit, can never be the interest of any trading nation; but must lay them under disadvantages, by encreasing money beyond its natural proportion to labour and commodities, and thereby heightening their price to the merchant and manufacturer. And in this view, it must be allowed, that no bank could be more advantageous, than such a one as locked up all the money it received, and never augmented the circulating coin, as is usual, by returning part of its treasure into commerce.

You can find similar language in “On the Balance of Trade”:

I scarcely know any method of sinking money below its level [i.e. producing inflation], but those institutions of banks, funds, and paper-credit, which are so much practised in this kingdom. These render paper equivalent to money, circulate it throughout the whole state, make it supply the place of gold and silver, raise proportionably the price of labour and commodities, and by that means either banish a great part of those precious metals, or prevent their farther encrease. What can be more shortsighted than our reasonings on this head? We fancy, because an individual would be much richer, were his stock of money doubled, that the same good effect would follow were the money of every one encreased; not considering, that this would raise as much the price of every commodity, and reduce every man, in time, to the same condition as before.

It is indeed evident, that money is nothing but the representation of labour and commodities, and serves only as a method of rating or estimating them. Where coin is in greater plenty; as a greater quantity of it is required to represent the same quantity of goods; it can have no effect, either good or bad, taking a nation within itself; any more than it would make an alteration on a merchant’s books, if, instead of the Arabian method of notation, which requires few characters, he should make use of the Roman, which requires a great many. 

From this view — which is, again, just taking the neutrality of money to its logical conclusion — services like the ones being advertised on the F train are the exact opposite of what we want. By making more goods usable as money, they are only contributing to inflation. Rather than making it easier for people to use necklaces, furniture, etc. as means of payment, we should rather be discouraging people form using even currency as means of payment, by reducing banks to safe-deposit boxes.

That was where Hume left the matter when he first wrote the essays around 1750. But when he republished “On the Balance of Trade” in 1764, he was no longer so confident. [1] The new edition added a discussion of the development of banking in Scotland with a strikingly different tone:

It must, however, be confessed, that, as all these questions of trade and money are extremely complicated, there are certain lights, in which this subject may be placed, so as to represent the advantages of paper-credit and banks to be superior to their disadvantages. … The encrease of industry and of credit … may be promoted by the right use of paper-money. It is well known of what advantage it is to a merchant to be able to discount his bills upon occasion; and every thing that facilitates this species of traffic is favourable to the general commerce of a state. But private bankers are enabled to give such credit by the credit they receive from the depositing of money in their shops; and the bank of England in the same manner, from the liberty it has to issue its notes in all payments. There was an invention of this kind, which was fallen upon some years ago by the banks of Edinburgh; and which, as it is one of the most ingenious ideas that has been executed in commerce, has also been thought advantageous to Scotland. It is there called a Bank-Credit; and is of this nature. A man goes to the bank and finds surety to the amount, we shall suppose, of a 1000 pounds. This money, or any part of it, he has the liberty of drawing out whenever he pleases, and he pays only the ordinary interest for it, while it is in his hands. … The advantages, resulting from this contrivance, are manifold. As a man may find surety nearly to the amount of his substance, and his bank-credit is equivalent to ready money, a merchant does hereby in a manner coin his houses, his household furniture, the goods in his warehouse, the foreign debts due to him, his ships at sea; and can, upon occasion, employ them in all payments, as if they were the current money of the country.

Hume is describing something like a secured line of credit, not so different from the services being advertised on the F line, which also offer ways to coin your houses and household furniture. The puzzle is why he thinks this is a good thing. The trade credit provided by banks, which is now “favourable to the general commerce of the state,” is precisely what he was trying to prevent when he wrote that the best bank was one that “locked up all the money it received.”Why does he now think that increasing liquidity will stimulate industry, instead of just producing a rise in prices that will “reduce every man, in time, to the same condition as before”?

You can’t really hold it against Hume that he never resolved this contradiction. But what’s striking is how little the debate has advanced in the 250 years since. Indeed, in some ways it’s regressed. Hume at least drew the logical conclusion that in a world of neutral money, liquidity services like the ones advertised on the F train would not exist.

[1] I hadn’t realized this section was a later addition until reading Arie Arnon’s discussion of the essay in Monetary Theory and Policy from Hume and Smith to Wicksell. I hope to be posting more about this superb book in the near future.

Gurley and Shaw on Banking

Gurley and Shaw (1956), “Financial Intermediaries in the Saving-Investment Process”:

As intermediaries, banks buy primary securities and issue, in payment for them, deposits and currency. As the payments mechanism, banks transfer title to means of payment on demand by customers. It has been pointed out before, especially by Henry Simons, that these two banking functions are at least incompatible. As managers of the payments mechanism, the banks cannot afford a shadow of insolvency. As intermediaries in a growing economy, the banks may rightly be tempted to wildcat. They must be solvent or the community will suffer; they must dare insolvency or the community will fail to realize its potentialities for growth. 

All too often in American history energetic intermediation by banks has culminated in collapse of the payments mechanism. During some periods, especially cautious regard for solvency has resulted in collapse of bank intermediation.  Each occasion that has demonstrated the incompatibility of the two principal banking functions has touched off a flood of financial reform. These reforms on balance have tended to emphasize bank solvency and the viability of the payments mechanism at the expense of bank participation in financial growth. They have by no means gone to the extreme that Simons proposed, of divorcing the two functions altogether, but they have tended in that direction rather than toward endorsement of wildcat banking. This bias in financial reform has improved the opportunities for non-monetary intermediaries. The relative retrogression in American banking seems to have resulted in part from regulatory suppression of the intermediary function. 

Turning to another matter, it has seemed to be a distinctive, even magic, characteristic of the monetary system that it can create money, erecting a “multiple expansion”of debt in the form of deposits and currency on a limited base of reserves. Other financial institutions, conventional doctrine tells us, are denied this creative or multiplicative faculty. They are merely middlemen or brokers, not manufacturers of credit. Our own view is different. There is no denying, of course, that the monetary system creates debt in the special form of money: the monetary system can borrow by issue of instruments that are means of payment. There is no denying, either, that non-monetary intermediaries cannot create this same form of debt. … 

However, each kind of non-monetary intermediary can borrow, go into debt, issue its own characteristic obligations – in short, it can create credit, though not in monetary form. Moreover, the non-monetaryintermediaries are less inhibited in their own style of credit creation than are the banks in creating money. Credit creation by non-monetary intermediaries is restricted by various qualitative rules. Aside from these, the main factor that limits credit creation is the profit calculus. Credit creation by banks also is subject to the profit condition. But the monetary system is subject not only to this restraint and to a complex of qualitative rules. It is committed to a policy restraint, of avoiding excessive expansion or contraction of credit for the community’s welfare, that is not imposed explicitly on non-monetary intermediaries. It is also held in check by a system of reserve requirements. … The [money multiplier] is a remarkable phenomenon not because of its inflationary implications but because it means that bank expansion is anchored, as other financial expansion is not, to a regulated base. If credit creation by banks is miraculous, creation of credit by other financial institutions is still more a cause for exclamation. 

The first paragraph of this long footnote is a succinct statement of a basic tension in bank regulation that remains unresolved. (Recall that Simons’ proposal to eliminate the intermediation function of banks was recently revived by Michel Kumhof at the IMF.) The other two paragraphs are a good clear statement of the argument I’ve been trying to develop on this blog, that there is no fundamental difference between money and other forms of financial claims, and a macroeconomically meaningful “quantity of money” was an artifact of mid-20th century regulatory arrangements.

Don’t Start from the Coin


Even today, textbooks on Money, Currency, and Banking are more likely than not to begin with an analysis of a state of things in which legal-tender ‘money’ is the only means of paying and lending. The huge system of credits and debits, of claims and debts, by which capitalist society carries on its daily business of production and consumption is then built up step by step by introducing claims to money or credit instruments that act as substitutes for legal tender… Even when there is very little left of [money’s] fundamental role in practice, everything that happens in the sphere of currency, credit, and banking is construed from it, just as the case of money itself is construed from barter. 

Historically, this method of building up the analysis of money, currency, and banking is readily understandable… Legal constructions, too, … were geared to a sharp distinction between money as the only genuine and ultimate means of payment and the credit instrument that embodied a claim to money. But logically, it is by no means clear that the most useful method is to start from the coin—even if, making a concession to realism, we add inconvertible government paper—in order to proceed to the credit transactions of reality. It may be more useful to start from these in the first place, to look upon capitalist finance as a clearing system that cancels claims and debts and carries forward the differences—so that ‘money’ payments come in only as a special case without any particularly fundamental importance. In other words: practically and analytically, a credit theory of money is possibly preferable to a monetary theory of credit.

Perry Mehrling quotes this passage at the start of his essay Modern Money: Credit or Fiat. If you’re someone who worries about the vexed question of what is money anyway, you will benefit from the sustained intelligence Perry brings to bear on it.

Readers of this blog may not be familiar with Perry’s work, so let me suggest a few things. The Credit or Fiat essay is a review of one of Randy Wray’s books, but it makes important positive arguments along with the negative criticism of MMT. [1] A good recent statement of Mehrling’s own views on the monetary system is The Inherent Hierarchy of Money. Two superb essays on monetary thought in the postwar neoclassical synthesis are The Money Muddle and MIT and Money. [2] The former of these coins the term “monetary Walrasianism.” This refers to  the idea that the way to think of a monetary economy is a barter system where, for whatever reason, the nth good serves as unit of account and must be on one side of all trades.  This way of thinking about money is so ingrained that I suspect that many economists would be puzzled by the suggestion that there is any other way of thinking about money. But as Perry shows, this is a specific idea with its own history, to which we can and should imagine alternatives. Finally, The Vision of Hyman Minsky is one of the two best essays I know giving a systematic account of Minsky’s, well, vision. (The other is Minsky as Hedgehog by Dymski and Pollin.) Anyone interested in what money is, what “money” means, and what’s wrong with economists’ answers, could save themselves a lot of trouble and wrong turns by reading those essays. [3]

But let’s talk about the Schumpeter quote.  I think it is right. To understand the monetary nature of modern economies, you need to begin with the credit system, that is, the network of money obligations. Where we want to start from is a world of IOUs. Suppose the only means of payment is a promise to pay. Suppose it’s not only possible for me to tell the bartender at the end of the night, I’ll pay you later, suppose there’s nothing else I can tell him — there’s no cash register at the bar, just a box where my tab goes. Money still exists in this system, but it is only a money of account — concretely we can imagine either an arbitrary unit of value, or some notional commodity that does not circulate, or even exist. (Historical example: non-circulating gold in medieval Europe.) If you give something to me, or do something for me, the only thing I can pay you with now is a promise to pay you later.

This might seem paradoxical — jam tomorrow but never jam today — but it’s not. Debts in this system are eventually settled. As Schumpeter says, they’re settled by netting my IOUs to you from your IOUs to me. An important question then becomes, how big is the universe across which we can cancel out debts? If A owes B, B owes C, and C owes A, it’s not hard to settle everyone up. But suppose A owes B who owes C who owes …. who owes M who owes … who owes Z, who owes A. It’s not so easy now for the dbets to be transferred back along the chain for settlement. In any case, though, my willingness to accept your IOUs depends on my belief that I will want to make some payment to you in the future, or that I’ll want to make some payment to someone who will want to make a payment to someone …. who will eventually want to make a payment to you. The longer the chain, the more important it is for their to be some setting where all the various debts are toted up and canceled out.

The great fairs of medieval Europe were exactly this. During their normal dealings, merchants paid each other with bills of exchange, essentially IOUs that could be transferred to third parties. Merchants would pay suppliers by transferring (with their own endorsement) bills from their customers. Then periodically, merchant houses would send representatives to Champagne or wherever, where the various bills could be presented for payment. Almost all the obligations would end up being offsetting. From Braudel, Capitalism and Civilization Vol. 2:

… the real business of the fairs, economically speaking, was the activity of the great merchant houses. … No fair failed to end with a ‘payment session’ as at Linz, the great fair in Austria; at Leipzig, from its early days of prosperity, the last week was for settling up, the Zahlwoche. Even at Lanciano, a little town in the Papal States which was regularly submerged by its fair (though the latter was only of modest dimensions), handfuls of bills of exchange converged on the fair. The same was true of Pezenas or Montagnac, whose fairs relayed those of Beaucaire and were of similar quality: a whole series of bills of exchange on Paris or Lyons travelled to them. 

The fairs were effectively a settling of accounts, in which debts met and cancelled each other out, melting like snow in the sun: such were the miracles of scontro, compensation. A hundred thousand or so “ecus d’or en or” – that is real coins – might at the clearing-house of Lyons settle business worth millions; all the more so as a good part of the remaining debts would be settled either by a promise of payment on another exchange (a bill of exchange) or by carrying over payment until the next fair: this was the deposito which was usually paid for at 10% a year (2.5% for three months). 

This was not a pure credit-money system, since coin could be used to settle obligations for which there was no offsetting bill. But note that a “good part” of the net obligations remaining at the end of the fair were simply carried over to the next fair.

I think it would be helpful if we replaced truck-and-barter with something like these medieval fairs, when we imagine the original economic situation. [4] Starting from a credit view of money modifies our intuitions in several, as I see it, helpful ways.

1. Your budget constraint is always a matter of how much people will lend you, or how safe you feel borrowing. Conversely, the consequences of failing to pay your debts is a fundamental parameter. We can’t push bankruptcy onto the back burner as a tricky but secondary question to be dealt with later.

2. The extension of credit goes with an extension of the realm of the market. The more things you might be willing to do to settle your debts, the more willing I am to lend to you. And conversely, the further what you owe runs beyond your normal income, the more the question of what you won’t do for money comes up for negotiation.

3. Liquidity, money, demand, depend ultimately on people’s willingness to trust each other, to accept promises, to have confidence in things working out according to plan. Liquidity exists on the liability side of balance sheets as much as on the asset side.

4. When we speak of more or less liquidity, we don’t mean a greater or lesser quantity of some commodity designated “money,” but a greater or lesser degree of willingness to extend credit. So at bottom, conventional monetary policy, quantitative easing, lender of last resort operations, bank regulations — they’re all the same thing.

When Minsky says that the fundamental function of banks is “acceptance,” this is what he means. The fundamental question faced by the financial system is, whose promises are good?

[1] I don’t want to get into Perry criticisms of MMT here. Anyone interested should read the article, it’s not long.

[2] MIT and Money also makes it clear that I was wrong to pick Samuelson’s famous consumption-loan essay as an illustration of the neoclassical position on interest rates. The point of that essay, he explains, was not to offer a theory of interest rate determination, but rather to challenge economic conservatives by demonstrating that even in a simple, rigorous model of rational optimization, a public pension system could could be an unambiguous welfare improvement over private retirement saving. My argument wasn’t wrong, but I should have picked a better example of what I was arguing against.

[3] Perry has also written three books. The only one I’ve read is The New Lombard Street. I can’t recommend it as a starting point for someone new to his work: It’s too focused on the specific circumstances of the financial crisis of 2008, and assumes too much familiarity with his larger perspective.

EDIT: I removed some overly belligerent language from the first footnote.