Posts Tagged 'Don Patinkin'

Explaining the Hegemony of New Classical Economics

Simon Wren-Lewis, Robert Waldmann, and Paul Krugman have all recently devoted additional space to explaining – ruefully, for the most part – how it came about that New Classical Economics took over mainstream macroeconomics just about half a century after the Keynesian Revolution. And Mark Thoma got them all started by a complaint about the sorry state of modern macroeconomics and its failure to prevent or to cure the Little Depression.

Wren-Lewis believes that the main problem with modern macro is too much of a good thing, the good thing being microfoundations. Those microfoundations, in Wren-Lewis’s rendering, filled certain gaps in the ad hoc Keynesian expenditure functions. Although the gaps were not as serious as the New Classical School believed, adding an explicit model of intertemporal expenditure plans derived from optimization conditions and rational expectations, was, in Wren-Lewis’s estimation, an improvement on the old Keynesian theory. The improvements could have been easily assimilated into the old Keynesian theory, but weren’t because New Classicals wanted to junk, not improve, the received Keynesian theory.

Wren-Lewis believes that it is actually possible for the progeny of Keynes and the progeny of Fisher to coexist harmoniously, and despite his discomfort with the anti-Keynesian bias of modern macroeconomics, he views the current macroeconomic research program as progressive. By progressive, I interpret him to mean that macroeconomics is still generating new theoretical problems to investigate, and that attempts to solve those problems are producing a stream of interesting and useful publications – interesting and useful, that is, to other economists doing macroeconomic research. Whether the problems and their solutions are useful to anyone else is perhaps not quite so clear. But even if interest in modern macroeconomics is largely confined to practitioners of modern macroeconomics, that fact alone would not conclusively show that the research program in which they are engaged is not progressive, the progressiveness of the research program requiring no more than a sufficient number of self-selecting econ grad students, and a willingness of university departments and sources of research funding to cater to the idiosyncratic tastes of modern macroeconomists.

Robert Waldmann, unsurprisingly, takes a rather less charitable view of modern macroeconomics, focusing on its failure to discover any new, previously unknown, empirical facts about macroeconomic, or to better explain known facts than do alternative models, e.g., by more accurately predicting observed macro time-series data. By that, admittedly, demanding criterion, Waldmann finds nothing progressive in the modern macroeconomics research program.

Paul Krugman weighed in by emphasizing not only the ideological agenda behind the New Classical Revolution, but the self-interest of those involved:

Well, while the explicit message of such manifestos is intellectual – this is the only valid way to do macroeconomics – there’s also an implicit message: from now on, only my students and disciples will get jobs at good schools and publish in major journals/ And that, to an important extent, is exactly what happened; Ken Rogoff wrote about the “scars of not being able to publish stick-price papers during the years of new classical repression.” As time went on and members of the clique made up an ever-growing share of senior faculty and journal editors, the clique’s dominance became self-perpetuating – and impervious to intellectual failure.

I don’t disagree that there has been intellectual repression, and that this has made professional advancement difficult for those who don’t subscribe to the reigning macroeconomic orthodoxy, but I think that the story is more complicated than Krugman suggests. The reason I say that is because I cannot believe that the top-ranking economics departments at schools like MIT, Harvard, UC Berkeley, Princeton, and Penn, and other supposed bastions of saltwater thinking have bought into the underlying New Classical ideology. Nevertheless, microfounded DSGE models have become de rigueur for any serious academic macroeconomic theorizing, not only in the Journal of Political Economy (Chicago), but in the Quarterly Journal of Economics (Harvard), the Review of Economics and Statistics (MIT), and the American Economic Review. New Keynesians, like Simon Wren-Lewis, have made their peace with the new order, and old Keynesians have been relegated to the periphery, unable to publish in the journals that matter without observing the generally accepted (even by those who don’t subscribe to New Classical ideology) conventions of proper macroeconomic discourse.

So I don’t think that Krugman’s ideology plus self-interest story fully explains how the New Classical hegemony was achieved. What I think is missing from his story is the spurious methodological requirement of microfoundations foisted on macroeconomists in the course of the 1970s. I have discussed microfoundations in a number of earlier posts (here, here, here, here, and here) so I will try, possibly in vain, not to repeat myself too much.

The importance and desirability of microfoundations were never questioned. What, after all, was the neoclassical synthesis, if not an attempt, partly successful and partly unsuccessful, to integrate monetary theory with value theory, or macroeconomics with microeconomics? But in the early 1970s the focus of attempts, notably in the 1970 Phelps volume, to provide microfoundations changed from embedding the Keynesian system in a general-equilibrium framework, as Patinkin had done, to providing an explicit microeconomic rationale for the Keynesian idea that the labor market could not be cleared via wage adjustments.

In chapter 19 of the General Theory, Keynes struggled to come up with a convincing general explanation for the failure of nominal-wage reductions to clear the labor market. Instead, he offered an assortment of seemingly ad hoc arguments about why nominal-wage adjustments would not succeed in reducing unemployment, enabling all workers willing to work at the prevailing wage to find employment at that wage. This forced Keynesians into the awkward position of relying on an argument — wages tend to be sticky, especially in the downward direction — that was not really different from one used by the “Classical Economists” excoriated by Keynes to explain high unemployment: that rigidities in the price system – often politically imposed rigidities – prevented wage and price adjustments from equilibrating demand with supply in the textbook fashion.

These early attempts at providing microfoundations were largely exercises in applied price theory, explaining why self-interested behavior by rational workers and employers lacking perfect information about all potential jobs and all potential workers would not result in immediate price adjustments that would enable all workers to find employment at a uniform market-clearing wage. Although these largely search-theoretic models led to a more sophisticated and nuanced understanding of labor-market dynamics than economists had previously had, the models ultimately did not provide a fully satisfactory account of cyclical unemployment. But the goal of microfoundations was to explain a certain set of phenomena in the labor market that had not been seriously investigated, in the hope that price and wage stickiness could be analyzed as an economic phenomenon rather than being arbitrarily introduced into models as an ad hoc, albeit seemingly plausible, assumption.

But instead of pursuing microfoundations as an explanatory strategy, the New Classicals chose to impose it as a methodological prerequisite. A macroeconomic model was inadmissible unless it could be explicitly and formally derived from the optimizing choices of fully rational agents. Instead of trying to enrich and potentially transform the Keynesian model with a deeper analysis and understanding of the incentives and constraints under which workers and employers make decisions, the New Classicals used microfoundations as a methodological tool by which to delegitimize Keynesian models, those models being insufficiently or improperly microfounded. Instead of using microfoundations as a method by which to make macroeconomic models conform more closely to the imperfect and limited informational resources available to actual employers deciding to hire or fire employees, and actual workers deciding to accept or reject employment opportunities, the New Classicals chose to use microfoundations as a methodological justification for the extreme unrealism of the rational-expectations assumption, portraying it as nothing more than the consistent application of the rationality postulate underlying standard neoclassical price theory.

For the New Classicals, microfoundations became a reductionist crusade. There is only one kind of economics, and it is not macroeconomics. Even the idea that there could be a conceptual distinction between micro and macroeconomics was unacceptable to Robert Lucas, just as the idea that there is, or could be, a mind not reducible to the brain is unacceptable to some deranged neuroscientists. No science, not even chemistry, has been reduced to physics. Were it ever to be accomplished, the reduction of chemistry to physics would be a great scientific achievement. Some parts of chemistry have been reduced to physics, which is a good thing, especially when doing so actually enhances our understanding of the chemical process and results in an improved, or more exact, restatement of the relevant chemical laws. But it would be absurd and preposterous simply to reject, on supposed methodological principle, those parts of chemistry that have not been reduced to physics. And how much more absurd would it be to reject higher-level sciences, like biology and ecology, for no other reason than that they have not been reduced to physics.

But reductionism is what modern macroeconomics, under the New Classical hegemony, insists on. No exceptions allowed; don’t even ask. Meekly and unreflectively, modern macroeconomics has succumbed to the absurd and arrogant methodological authoritarianism of the New Classical Revolution. What an embarrassment.

UPDATE (11:43 AM EDST): I made some minor editorial revisions to eliminate some grammatical errors and misplaced or superfluous words.

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Who’s Afraid of Say’s Law?

There’s been a lot of discussion about Say’s Law in the blogosphere lately, some of it finding its way into the comments section of my recent post “What Does Keynesisan Mean,” in which I made passing reference to Keynes’s misdirected tirade against Say’s Law in the General Theory. Keynes wasn’t the first economist to make a fuss over Say’s Law. It was a big deal in the nineteenth century when Say advanced what was then called the Law of the Markets, pointing out that the object of all production is, in the end, consumption, so that all productive activity ultimately constitutes a demand for other products. There were extended debates about whether Say’s Law was really true, with Say, Ricardo, James and John Stuart Mill all weighing on in favor of the Law, and Malthus and the French economist J. C. L. de Sismondi arguing against it. A bit later, Karl Marx also wrote at length about Say’s Law, heaping his ample supply of scorn upon Say and his Law. Thomas Sowell’s first book, I believe drawn from the doctoral dissertation he wrote under George Stigler, was about the classical debates about Say’s Law.

The literature about Say’s Law is too vast to summarize in a blog post. Here’s my own selective take on it.

Say was trying to refute a certain kind of explanation of economic crises, and what we now would call cyclical or involuntary unemployment, an explanation attributing such unemployment to excess production for which income earners don’t have enough purchasing power in their pockets to buy. Say responded that the reason why income earners had supplied the services necessary to produce the available output was to earn enough income to purchase the output. This is the basic insight behind the famous paraphrase (I don’t know if it was Keynes’s paraphrase or someone else’s) of Say’s Law — supply creates its own demand. If it were instead stated as products or services are supplied only because the suppliers want to buy other products or services, I think that it would be more in sync than the standard formulation with Say’s intent. Another way to think about Say’s Law is as a kind of conservation law.

There were two famous objections made to Say’s Law: first, current supply might be offered in order to save for future consumption, and, second, current supply might be offered in order to add to holdings of cash. In either case, there could be current supply that is not matched by current demand for output, so that total current demand would be insufficient to generate full employment. Both these objections are associated with Keynes, but he wasn’t the first to make either of them. The savings argument goes back to the nineteenth century, and the typical response was that if there was insufficient current demand, because the desire to save had increased, the public deciding to reduce current expenditures on consumption, the shortfall in consumption demand would lead to an increase in investment demand driven by falling interest rates and rising asset prices. In the General Theory, Keynes proposed an argument about liquidity preference and a potential liquidity trap, suggesting a reason why the necessary adjustment in the rate of interest would not necessarily occur.

Keynes’s argument about a liquidity trap was and remains controversial, but the argument that the existence of money implies that Say’s Law can be violated was widely accepted. Indeed, in his early works on business-cycle theory, F. A. Hayek made the point, seemingly without embarrassment or feeling any need to justify it at length, that the existence of money implied a disconnect between overall supply and overall demand, describing money as a kind of loose joint in the economic system. This argument, apparently viewed as so trivial or commonplace by Hayek that he didn’t bother proving it or citing authority for it, was eventually formalized by the famous market-socialist economist (who, for a number of years was a tenured professor at that famous bastion of left-wing economics the University of Chicago) Oskar Lange who introduced a distinction between Walras’s Law and Say’s Law (“Say’s Law: A Restatement and Criticism”).

Walras’s Law says that the sum of all excess demands and excess supplies, evaluated at any given price vector, must identically equal zero. The existence of a budget constraint makes this true for each individual, and so, by the laws of arithmetic, it must be true for the entire economy. Essentially, this was a formalization of the logic of Say’s Law. However, Lange showed that Walras’s Law reduces to Say’s Law only in an economy without money. In an economy with money, Walras’s Law means that there could be an aggregate excess supply of all goods at some price vector, and the excess supply of goods would be matched by an equal excess demand for money. Aggregate demand would be deficient, and the result would be involuntary unemployment. Thus, according to Lange’s analysis, Say’s Law holds, as a matter of necessity, only in a barter economy. But in an economy with money, an excess supply of all real commodities was a logical possibility, which means that there could be a role for some type – the choice is yours — of stabilization policy to ensure that aggregate demand is sufficient to generate full employment. One of my regular commenters, Tom Brown, asked me recently whether I agreed with Nick Rowe’s statement: “the goal of good monetary policy is to try to make Say’s Law true.” I said that I wasn’t sure what the statement meant, thereby avoiding the need to go into a lengthy explanation about why I am not quite satisfied with that way of describing the goal of monetary policy.

There are at least two problems with Lange’s formulation of Say’s Law. The first was pointed out by Clower and Leijonhufvud in their wonderful paper (“Say’s Principle: What It Means and Doesn’t Mean” reprinted here and here) on what they called Say’s Principle in which they accepted Lange’s definition of Say’s Law, while introducing the alternative concept of Say’s Principle as the supply-side analogue of the Keynesian multiplier. The key point was to note that Lange’s analysis was based on the absence of trading at disequilibrium prices. If there is no trading at disequilibrium prices, because the Walrasian auctioneer or clearinghouse only processes information in a trial-and-error exercise aimed at discovering the equilibrium price vector, no trades being executed until the equilibrium price vector has been discovered (a discovery which, even if an equilibrium price vector exists, may not be made under any price-adjustment rule adopted by the auctioneer, rational expectations being required to “guarantee” that an equilibrium price vector is actually arrived at, sans auctioneer), then, indeed, Say’s Law need not obtain in notional disequilibrium states (corresponding to trial price vectors announced by the Walrasian auctioneer or clearinghouse). The insight of Clower and Leijonhufvud was that in a real-time economy in which trading is routinely executed at disequilibrium prices, transactors may be unable to execute the trades that they planned to execute at the prevailing prices. But when planned trades cannot be executed, trading and output contract, because the volume of trade is constrained by the lesser of the amount supplied and the amount demanded.

This is where Say’s Principle kicks in; If transactors do not succeed in supplying as much as they planned to supply at prevailing prices, then, depending on the condition of their balances sheets, and the condition of credit markets, transactors may have to curtail their demands in subsequent periods; a failure to supply as much as had been planned last period will tend reduce demand in this period. If the “distance” from equilibrium is large enough, the demand failure may even be amplified in subsequent periods, rather than damped. Thus, Clower and Leijonhufvud showed that the Keynesian multiplier was, at a deep level, really just another way of expressing the insight embodied in Say’s Law (or Say’s Principle, if you insist on distinguishing what Say meant from Lange’s reformulation of it in terms of Walrasian equilibrium).

I should add that, as I have mentioned in an earlier post, W. H. Hutt, in a remarkable little book, clarified and elaborated on the Clower-Leijonhufvud analysis, explaining how Say’s Principle was really implicit in many earlier treatments of business-cycle phenomena. The only reservation I have about Hutt’s book is that he used it to wage an unnecessary polemical battle against Keynes.

At about the same time that Clower and Leijonhufvud were expounding their enlarged view of the meaning and significance of Say’s Law, Earl Thompson showed that under “classical” conditions, i.e., a competitive supply of privately produced bank money (notes and deposits) convertible into gold, Say’s Law in Lange’s narrow sense, could also be derived in a straightforward fashion. The demonstration followed from the insight that when bank money is competitively issued, it is accomplished by an exchange of assets and liabilities between the bank and the bank’s customer. In contrast to the naïve assumption of Lange (adopted as well by his student Don Patinkin in a number of important articles and a classic treatise) that there is just one market in the monetary sector, there are really two markets in the monetary sector: a market for money supplied by banks and a market for money-backing assets. Thus, any excess demand for money would be offset not, as in the Lange schema, by an excess supply of goods, but by an excess supply of money-backing services. In other words, the public can increase their holdings of cash by giving their IOUs to banks in exchange for the IOUs of the banks, the difference being that the IOUs of the banks are money and the IOUs of customers are not money, but do provide backing for the money created by banks. The market is equilibrated by adjustments in the quantity of bank money and the interest paid on bank money, with no spillover on the real sector. With no spillover from the monetary sector onto the real sector, Say’s Law holds by necessity, just as it would in a barter economy.

A full exposition can be found in Thompson’s original article. I summarized and restated its analysis of Say’s Law in my 1978 1985 article on classical monetary theory and in my book Free Banking and Monetary Reform. Regrettably, I did not incorporate the analysis of Clower and Leijonhufvud and Hutt into my discussion of Say’s Law either in my article or in my book. But in a world of temporary equilibrium, in which future prices are not correctly foreseen by all transactors, there are no strict intertemporal budget constraints that force excess demands and excess supplies to add up to zero. In short, in such a world, things can get really messy, which is where the Clower-Leijonhufvud-Hutt analysis can be really helpful in sorting things out.


About Me

David Glasner
Washington, DC

I am an economist in the Washington DC area. My research and writing has been mostly on monetary economics and policy and the history of economics. In my book Free Banking and Monetary Reform, I argued for a non-Monetarist non-Keynesian approach to monetary policy, based on a theory of a competitive supply of money. Over the years, I have become increasingly impressed by the similarities between my approach and that of R. G. Hawtrey and hope to bring Hawtrey's unduly neglected contributions to the attention of a wider audience.

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