ABCT without a Unique Natural Rate of Interest?

Well, this would be an improvement on that absurd theory, if it were possible.

A commentator on the last post complains that the Austrian business cycle theory (ABCT) – don’t you know?! – doesn’t even need a unique natural rate of interest / equilibrium rate of interest, despite the fact that every exposition of the theory I have seen relies on exactly that concept.

One can see this in Hayek’s Prices and Production:

“Put concisely, Wicksell’s theory is as follows: If it were not for monetary disturbances, the rate of interest would be determined so as to equalize the demand for and the supply of savings. This equilibrium rate, as I prefer to call it, he christens the natural rate of interest. In a money economy, the actual or money rate of interest (“Geldzins”) may differ from the equilibrium or natural rate, because the demand for and the supply of capital do not meet in their natural form but in the form of money, the quantity of which available for capital purposes may be arbitrarily changed by the banks. Now, so long as the money rate of interest coincides with the equilibrium rate, the rate of interest remains “neutral” in its effects on the prices of goods, tending neither to raise nor to lower them. When the banks, however, lower the money rate of interest below the equilibrium rate, which they can do by lending more than has been entrusted to them, i.e., by adding to the circulation, this must tend to raise prices; if they raise the money rate above the equilibrium rate—a case of less practical importance—they exert a depressing influence on prices.” (Hayek 2008 [1931]: 215).

One should note that emphasis on a single “equilibrium” or “natural” rate here. Roger Garrison, the leading modern exponent of ABCT, uses the same concept called a market-clearing or equilibrium rate:

“The supply and demand for loanable funds … identify a market-clearing, or equilibrium, rate of interest ..., at which saving (S) and investment (I) are brought into equality.” (Garrison 2000: 39).

On that same page in Time and Money: The Macroeconomics of Capital Structure (2000), Garrison makes it clear that this rate is essentially the Wicksellian rate causing intertemporal equilibrium.

So where are the Austrian scholars expounding their trade cycle theory with Sraffa’s multiple natural rates? The only work I have ever seen that could be seen as an improvement on the standard Austrian theory is that of Robert Murphy in this paper:

Robert P. Murphy, “Multiple Interest Rates and Austrian Business Cycle Theory.”

Commenting on the Hayek–Sraffa exchange in 1932, Murphy points out the following:

“In his brief remarks [sc. in reply to Sraffa], Hayek certainly did not fully reconcile his analysis of the trade cycle with the possibility of multiple own-rates of interest. Moreover, Hayek never did so later in his career. His Pure Theory of Capital (1975 [1941]) explicitly avoided monetary complications, and he never returned to the matter. Unfortunately, Hayek’s successors have made no progress on this issue, and in fact, have muddled the discussion. As I will show in the case of Ludwig Lachmann—the most prolific Austrian writer on the Sraffa-Hayek dispute over own-rates of interest—modern Austrians not only have failed to resolve the problem raised by Sraffa, but in fact no longer even recognize it.

Austrian expositions of their trade cycle theory never incorporated the points raised during the Sraffa-Hayek debate. Despite several editions, Mises’ magnum opus (1998 [1949]) continued to talk of “the” originary rate of interest, corresponding to the uniform premium placed on present versus future goods. The other definitive Austrian treatise, Murray Rothbard’s (2004 [1962]) Man, Economy, and State, also treats the possibility of different commodity rates of interest as a disequilibrium phenomenon that would be eliminated through entrepreneurship. To my knowledge, the only Austrian to specifically elaborate on Hayekian cycle theory vis-à-vis Sraffa’s challenge is Ludwig Lachmann.”
(Murphy, “Multiple Interest Rates and Austrian Business Cycle Theory,” pp. 11–12).

Murphy, to his credit, has pinpointed a very severe problem with modern ABCT (and I suppose it’s not a surprise to readers if I say he’s become one of favourite Austrians, not least of all because he supports a monetary theory of the interest rate).

Murphy denies the existence of a unique natural rate, but he has yet to produce any work showing how ABCT actually works with its non-existence. On pp. 19–23 of his discussion of the subject in a very simple model, Murphy provides his attempt to show how an inflationary increase in the money supply can cause “people in earlier periods to consume too much,” but even he admits this is “not really an illustration of the Misesian trade cycle theory,” because his model does not “really exhibit malinvestments in longer production processes.” Murphy leaves the creation of such a model for his future research. He’s done no such research as yet. Nor has any other Austrian.

BIBLIOGRAPHY

Garrison, R. W. 2000. Time and Money: The Macroeconomics of Capital Structure, Routledge, London and New York.

Hayek, F. A. von, 2008. Prices and Production and Other Works: F. A. Hayek on Money, the Business Cycle, and the Gold Standard, Ludwig von Mises Institute, Auburn, Ala.

Robert P. Murphy, “Multiple Interest Rates and Austrian Business Cycle Theory.”

Robert P. Murphy on the Sraffa-Hayek Debate

Robert P. Murphy has posted this paper on this blog:

Robert P. Murphy, “Multiple Interest Rates and Austrian Business Cycle Theory.”

On the Sraffa versus Hayek debate, Murphy has some valuable remarks. When Sraffa demonstrated that outside of equilibrium there is no single natural rate of interest in a barter or money-using economy, Hayek never really addressed this problem for his trade cycle theory.

Murphy points out the following:

“In his brief remarks, Hayek certainly did not fully reconcile his analysis of the trade cycle with the possibility of multiple own-rates of interest. Moreover, Hayek never did so later in his career. His Pure Theory of Capital (1975 [1941]) explicitly avoided monetary complications, and he never returned to the matter. Unfortunately, Hayek’s successors have made no progress on this issue, and in fact, have muddled the discussion. As I will show in the case of Ludwig Lachmann—the most prolific Austrian writer on the Sraffa-Hayek dispute over own-rates of interest—modern Austrians not only have failed to resolve the problem raised by Sraffa, but in fact no longer even recognize it.

Austrian expositions of their trade cycle theory never incorporated the points raised during the Sraffa-Hayek debate. Despite several editions, Mises’ magnum opus (1998 [1949]) continued to talk of “the” originary rate of interest, corresponding to the uniform premium placed on present versus future goods. The other definitive Austrian treatise, Murray Rothbard’s (2004 [1962]) Man, Economy, and State, also treats the possibility of different commodity rates of interest as a disequilibrium phenomenon that would be eliminated through entrepreneurship. To my knowledge, the only Austrian to specifically elaborate on Hayekian cycle theory vis-à-vis Sraffa’s challenge is Ludwig Lachmann.”
(Murphy, “Multiple Interest Rates and Austrian Business Cycle Theory,” pp. 11–12).

Murphy then discusses Lachmann’s (1994: 154) solution to Sraffa’s critique, but finds it wanting:

“Lachmann’s demonstration—that once we pick a numéraire, entrepreneurship will tend to ensure that the rate of return must be equal no matter the commodity in which we invest—does not establish what Lachmann thinks it does. The rate of return (in intertemporal equilibrium) on all commodities must indeed be equal once we define a numéraire, but there is no reason to suppose that those rates will be equal regardless of the numéraire. As such, there is still no way to examine a barter economy, even one in intertemporal equilibrium, and point to “the” real rate of interest.”
(Murphy, “Multiple Interest Rates and Austrian Business Cycle Theory,” pp. 14).

On p. 14, Murphy states what I have already argued elsewhere: that Mises’s originary interest rate (a pure time preference theory of interest) becomes the “natural” rate imagined in Misesian versions of the trade cycle theory.

On pp. 19–23 in a simple model, Murphy provides his attempt to show how an inflationary increase in the money supply can cause “people in earlier periods to consume too much,” and his analysis in the (simple) model is fine, as far as it goes. But even he admits this is “not really an illustration of the Misesian trade cycle theory,” because his model does not “really exhibit malinvestments in longer production processes.” Murphy leaves the creation of such a model for his future research.

Murphy’s conclusions are significant:

“In summary, Austrians should familiarize themselves with the construct of a dynamic equilibrium, in which spot prices and other data can evolve over time, but where entrepreneurs fully anticipate such changes and squeeze out all pure profit opportunities. In this setting, there is no such thing as an objective real or natural rate of interest, so the Austrians cannot cling to their prescription that the banks ought to set the market rate to “the” natural rate. However, as our last scenario above hoped to convey, it still is true that an intertemporal, dynamic equilibrium can be disturbed if commercial banks inject new money into the credit markets. If a Misesian boom-bust cycle ensues, the reason is not that the banks charged a money right below “the” natural rate, because there is no such thing. Yet the basic Misesian analysis still holds true, that the bankers have suddenly augmented the purchasing power of one segment of the population, which not only redistributes real wealth but also leads to distorted money prices and more mistakes than otherwise would have occurred.”
(Robert P. Murphy, “Multiple Interest Rates and Austrian Business Cycle Theory,” p. 23).

So Murphy has dispensed with the Wicksellian natural interest rate concept, but still thinks a Misesian boom-bust cycle can occur. But this of course raises the following questions:

(1) Fractional reserve banking has always redistributed “real wealth” to those who first receive loans: usually it goes to capitalists who increase investment, employment and output to make us wealthier. Why is this a bad thing? Even loans extended under a pure gold standard would redistribute “real wealth” to the first holders of the money: the issue is whether real resources are available.

(2) What happens when new fiduciary media or fiat money can simply use idle resources, such as unemployed labour, unused stocks of raw materials, idle capital goods and other factor inputs?

(3) What happens when fiduciary media or fiat money can simply be used to import the relevant factor inputs through international trade, and these factor inputs are not scarce?

(4) Even when domestic factor inputs become scarce and an economy runs at full employment, and inflationary pressures build up, this is exactly the time when Keynesian macroeconomic policy has measures to deal with the boom: a contraction in demand to free up real resources for a further growth cycle.

At any rate, I am impressed with this paper by Murphy. Though I have not become a convert to ABCT, without any doubt Murphy’s paper is the best attempt to improve and build on the Austrian trade cycle theory I have seen in a long time.


BIBLIOGRAPHY

Lachmann, L. M. 1994. Expectations and the Meaning of Institutions: Essays in Economics (ed. by D. Lavoie), Routledge, London.

Murphy, Robert P. “Multiple Interest Rates and Austrian Business Cycle Theory.”

Robert P. Murphy on the Pure Time Preference Theory of the Interest Rate

The Austrian scholar Robert P. Murphy has made his PhD thesis available on his blog:

Robert P. Murphy, “Is Keynes from Heaven or Hell,” 7 July 2011.

The PhD is a study with three separate essays dealing with Austrian capital and interest rate theory. In the second essay, Murphy critiques the pure time preference theory of the interest rate (Murphy 2003: 58–126), and, in his third chapter, he supports a view of interest rates as purely monetary phenomena (Murphy 2003: 127–177).

In taking a monetary theory of the interest rate, Murphy is far closer to Keynes than the views of many of his fellow Austrians, and indeed in his blog post above he cites Keynes’ remarks on interest in Chapter 13 of the General Theory with measured approval (Robert P. Murphy, “Is Keynes from Heaven or Hell,” 7 July 2011).

Murphy’s PhD is also worth reading in its own right. Some highlights follow.

On p. 107 (n. 33), Murphy identifies some hypocrisy from Henry Hazlitt, who had condemned Keynes’s concept of “own rates of interest” as a “strange” idea and “nonsense,” even though Rothbard uses a similar concept in his analysis of interest in capital goods markets. Murphy contends that the pure time preference theory of interest rates “encourages exactly the type of thinking that Hazlitt finds so absurd” (Murphy 2003: 107, n. 33).

From pp. 100–107, one can read Murphy’s critique of the idea that a uniform rate of originary interest would arise amongst all individuals and in goods markets.

It is only in the imaginary “evenly rotating economy” (ERE), a stationary general equilibrium with “a world of certainty and unchanging conditions over time” (Murphy 2003: 103), that a uniform rate of originary interest would emerge. In a dynamic general equilibrium the uniform rate need not emerge.

Here Murphy invokes the Hayek–Sraffa exchange, and Ludwig Lachmann’s possible solution to the problem of the unique natural rate:

“What is much less clear to us is to what extent Hayek was aware that by admitting that there might be no single rate he was making a fatal concession to his opponent. If there is a multitude of commodity rates, it is evidently possible for the money rate of interest to be lower than some but higher than others. What, then, becomes of monetary equilibrium?” (Lachmann 1994: 154).

“It is not difficult, however, to close this particular breach in the Austrian rampart. In a barter economy with free competition commodity arbitrage would tend to establish an overall equilibrium rate of interest. Otherwise, if the wheat rate were the highest and the barley rate the lowest of interest rates, it would be profitable to borrow in barley and lend in wheat. Inter-market arbitrage will tend to establish an overall equilibrium in the loan market such that, in terms of a third commodity serving as numéraire, say steel, it is no more profitable to lend in wheat than in barley. This does not mean that actual own-rates must all be equal, but that their disparities are exactly offset by disparities between forward prices. The case is exactly parallel to the way in which international arbitrage produces equilibrium in the international money market, where differences in local interest rates are offset by disparities in forward rates” (Lachmann 1994: 154).

Murphy rejects Lachmann solution:

“Lachmann is defending Hayek from Sraffa’s claim that there is no reason for a unique ‘natural rate of interest.’ But Sraffa’s whole point was that there are, in principle, just as many natural rates as commodities; the fact that the rates in terms of any one commodity, such as steel, must be equal does not rescue Hayek. (One cannot explain the trade cycle as a deviation of the money rate of interest from ‘the’ natural rate of interest if the rate calculated in terms of steel is different from the natural rate calculated in terms of copper.) … arbitraging alone will not establish a unique real rate of interest in the way Lachmann seems to think.” (Murphy 2003: 102, n. 27).

According to Murphy, arbitrage would not lead to equalization of natural rates. As far as I can see, Murphy does not explore the consequences of this for the Hayekian versions of the Austrian trade cycle theory: if there is no unique natural rate of interest or tendency for such a unique rate, what becomes of the theory? This was the point of Sraffa’s critique of Hayek’s Prices and Production (Sraffa 1932a and 1932b).

Murphy concludes that interest is “quite simply the price of borrowing money or (what is the same thing) the exchange rate of present versus future money units” (Murphy 2003: 176).


BIBLIOGRAPHY

Lachmann, L. M. 1994. Expectations and the Meaning of Institutions: Essays in Economics (ed. by D. Lavoie), Routledge, London.

Murphy, Robert P. 2003. Unanticipated Intertemporal Change in Theories of Interest, PhD dissert., Department of Economics, New York University.

Sraffa, P. 1932a. “Dr. Hayek on Money and Capital,” Economic Journal 42: 42–53.

Sraffa, P. 1932b. “A Rejoinder,” Economic Journal 42 (June): 249–251.

Mises’s “Originary Interest Rate” Theory

Mises uses the Wicksellian natural interest rate in his earlier work on Austrian business cycle theory. But, by the time of Human Action (1949), Mises is employing an “originary interest rate” concept, and talk of the natural rate largely disappears. Mises explains the theory:

“Originary interest is the ratio of the value assigned to want-satisfaction in the immediate future and the value assigned to want-satisfaction in remote periods of the future. It manifests itself in the market economy in the discount of future goods as against present goods. It is a ratio of commodity prices, not a price in itself. There prevails a tendency toward the equalization of this ratio for all commodities. In the imaginary construction of the evenly rotating economy the rate of originary interest is the same for all commodities” (Mises 1998: 523).

This means that the originary interest is a future discounted good exchanging for a present good of higher value.

In terms of capital goods, this presumably means the discounted value of future goods against present goods that are borrowed now for capital goods investment.

But this is really just another real theory of the interest rate where loans are imagined as occurring in natura, or in real commodities in an economy at full employment. Mises is still subject to Sraffa’s critique of Hayek.

Curiosuly, when we turn to Roger Garrison we find the explicit use of the Wicksellian natural rate, as in Hayek’s work:

“So named by Swedish economist Knut Wicksell, the natural rate of interest is the rate that reflects the underlying real factors. In macroeconomic terms as applied to a wholly private economy, it is the rate that governs the allocation of resources between current consumption and investment for the future. By keeping saving and investment in balance, the natural rate guides the economy along a sustainable growth path. That is, governed by the natural rate, unconsumed current output (real saving) is used for augmenting the economy’s productive capacity in ways that are consistent with people’s willingness to postpone consumption. In the hands of the Austrian economists, the natural rate became the rate that reflects the time preferences of market participants and allocates resources among the temporally defined stages of production. The output of one stage serves as input to the next in this logical and broadly descriptive representation of the economy’s production process. The temporal dimension of the economy's capital structure is a key macroeconomic variable in Austrian theory. .... In summary terms, the natural rate is seen as an equilibrating rate. It is the rate that tells the truth about the availability of resources for meeting present and future consumer demands, allowing production plans to be kept in line with the preferred pattern of consumption. By implication, an unnatural, or artificial, rate of interest is a rate that reflects some extra-market influence and that creates a disconnection between intertemporal consumption preferences and intertemporal production plans” (Garrison 2006: 58–59).

So Garrison is also subject to same critique as Hayek. Yet in Garrison’s book Time and Money: The Macroeconomics of Capital Structure (London and New York, 2000), the word “Sraffa” does not (as far as I can see) even appear. It’s as if the Hayek–Sraffa exchange never occurred.


BIBLIOGRAPHY

Garrison, R. W. 2000. Time and Money: The Macroeconomics of Capital Structure, Routledge, London and New York.

Garrison, R. W. 2006. “Natural and Neutral Rates of Interest in Theory and Policy Formulation,” Quarterly Journal of Austrian Economics 9.4: 57–68.

Garrison, Roger W. 2007. “Natural and Neutral Rates of Interest in Theory and Policy Formulation,” Mises Daily, April 21
http://mises.org/daily/2513

Mises, L. 1998. Human Action: A Treatise on Economics, Mises Institute, Auburn, Ala.