[책] Piero Sraffa: Critical Assessments

지은이: John Wood (발행: Routledge, 1995. 3. 1. - 1408페이지)
자료: [구글도서] Piero Sraffa: Critical Assessments

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※ 발췌: of which some passages on page 45 begins:

On Hayek's Prices and Production

Hayek's four lectures delivered at the London School of Economics in February 1931 were published as "Prices and Production" in 1931. It was most enthusiastically received at the London School and won quick recognition with most reviews considering it favourably as an analytically rigorous work attempting to deal with money within the Walrasian-Austrian framework. Keynes's "Treatise on Money" also had appeared and was reviewed by Hayek around the same time. A keen controversy was thus developing between the two rival schools of Cambridge and London. Sraffa's review of the book appeared in ^The Economic Journal^ in March 1932, providing a jolt to the secured place the work was about to acquire.

As a staunch general equilibriumist, Hayek accepted without doubt that existence and uniqueness of competitive equilibrium established through the operation of the demand and supply forces and the ever-active principle of substitution that ensured its attainment. Not only does exist in a non-monetary real economy but, whenever a disturbance occurs, a new equilibrium is established rapidly. The equilibrium so attained gives full sway to the voluntary decisions of producers and consumers and forces are set against any interference with these decisions so that disequilibrium will not be tolerated long. Given the inherent and inevitabl tendency toward equilibrium operating in a real economy, all disequilibria and cyclical phenomena are to be ascribed to monetary factors. Thence Hayek investigates the characteristics of 'neutral' money, i.e., a kind of money which levels produvtion and the relative price of goods including the rate of interest 'undisturbed', exactly as they would be if there is no money at all. Hayek therefore first investigates the properties of the real system and the new equilibrium that it can attain when the decision to save is volunatarily made. In contrast, the situation is analysed when savings are 'forced' through external actions of banks lending credit to producers or consumers. Hayek end by suggesting that the only 'neutral' money is a constant quantity of money (i.e. quantum of money multiplied by velocity of circulation).

Sraffa acknowledges the definite contribution of the book in emphasising the effects of monetary changes on the relative prices of commodities rather than movements of the general price level on which attention until then had been exclusively focused by the quantity theory. Also the approaching of isolating, via the notion of neutral money (which is in Hayek, identical to a non-monetary economy) the effects of money on production and prices could itself 'have someting to recommend' as it would have led to a useful comparison between the condition of a specific non-monetary economy and thoe of various monetary systems. Such a comparison of a moneyless economy and various monetary systems in terms of the effects of assumed cases of disturbances in equilibrium would have been worthwhile as it would have revealed the essential characteristics common to every kind of money as well as their difference and provided comparative merits of alternative policies.

However, Sraffa points out that Hayek completely forgets to deal with this task. He neither traces the repercussions of using any one monetary system nor does he deal with money in any other role than purely as a medium of exchange. Hayek initially goes into a detailed exposition of the structure of a real economy, modelled along Austrian lines, with land and labour as the only means of production and all goods arranged into stages of production. Hayek assumes the structure to be triangular with the base representing output of consumer good and the height representing time elapsing between the first and the final stage of production. As in the Austrian theory, there is presumed a positive relation between the degree of roundaboutness of methods and their productivity and an inverse relation between the former(=roundaboutness) and the rate of interest. Hayek then traces out, assuming an initial equilibrium, the repercussions of a voluntary decision by consumers to change the rate of savings. The new equilibrium occurs at higher flow of consumption at lower prices. This situation is contrasted with 'forced savings', induced by the monetary policy(i.e., when the banks lending rate falls below the natural rate or bank advance credits to producers). In such a case, producers are encouraged to lengthen the period of production without the 'real savings'. This leads to inflationary price rises as factors are bid away from the consumer goods industries.  The real consumption levels get depressed. However this situation created through the extraneous intervention of banks cannot be perpetuatedㅡthe brake operates either throught the non-feasibility of continuing credit operations by banks or due to the natural tendency for consumers to expand their consumption when their money receipts rise again. Thus cycles are caused when the natural movement of prices is disturbed by the movements of money supply or extension of credits by the banking system. Hayek blamed the 'elastic'currency for recurrent disasters and favoured a constant or invariant money as being 'neutral'. In his view a money supply is not neutral even if it keeps 'the general price level stable'. In fact Hayek not only criticises the neglect of relative prices by the quantity theorists but also rejects the meaningfulness or the use of the 'general price level'.

While Hayek's criticism of the vagueness of the notion of general price level (which was nothing more that one of many possible index numbers of prices) was well founded, Sraffa criticises him for going further and rejecting "not only the notion of the general price-level but every notion of the value of money in any sense whatever". Sraffa notes that Hayek reduces the function of money to being a medium of exchange alone, ignoring that money is also a store of value, and the standard in terms of which debt, and other legal obligations, habits, opinions, conventions, in short all kinds of relations between men are more or less rigidly fixed"(p. 43). Regarding it purely as a medium of exchange 'deprives money of its essence' and it should then be inevitable, argues Sraffa, that when Hayek considers alternatie monetary policies, money should be found 'neutral' and its effects identically immaterial in every case. But, paradoxically, "Dr. Hayek invariably finds when he comes to compare alternative policies in regulating the emasculated money, that there is an all important difference in the results, and that it is 'neutral' only if it is kept constant in quality[this readers finds this a misprint of 'quanity'], whilst if the quantity is changed the most disastrous effects follow"(p. 44).

The source of this paradox is more closely examined by Sraffa taking Hayek's analysis of the difference between 'voluntary' and 'forced' savings and their consequences. Hayek suggests that, in the former case, the changes brought about in the structure are permanent as they follow voluntary decisions of individuals; in the latter, it is 'forced' through inflation and therefore the consumers can be expected to re-establish the initial position as soon as inflation ceases and their freedom of action is restored. Sraffa, in this article, does not contest the existence or stability of equilibrium in the system but argues that the second situation of 'forced savings' could be equally stable. "In the case of inflation, just a sthat of saving, the accumulation of capital takes place through a reduction of consumption." Hayek's presumption that the economy would revert back to less capitalist methods and higher consumption levels can have no basis. Emphasising the distributive implications of the inflationary process, Sraffa argues: "One class has, for a time, robbed another class of a part of their incomes; and has saved the plunder. When the robbery comes to an end, it is clear that the victims cannot possibly consume the capital which is now well out of their reach. If they are wage eaners, who have all the time consumed every penny of their income they have no wherewithal to expand consumption. And, if they are capitalists who have not shared in the plunder, they may indeed be induced to consume now a part of their capital by the fall in the rate of interest but not more so thatn if the rate had been lowered by the 'voluntary saving' of other people. Thus there could be no reversion to the previous position.

Further Sraffa criticises the asymmetrical reasoning Hayek adopts in distinguishing between credits extended by the banks to producers and to consumers. He holds, [:]

• on the one hand, that the artificial stimulant of inflation in the shape of producers' credits cannot do any good. 
• On the other hand, when consumers decide to save and additional credit is issued to them, Hayek finds that it would frustrate the effect of saving or that, in short, inflation working through consumer's credit would be effective in decreasing capital. 
• It is all the more surprising to have such asymmetry when one realises that the producer's volunatry decisions are treated differently from consumer's voluntary decisions. 

Summarising this paradox, Sraffa writes: "What has happened is simply that since money has been thoroughly 'neutralised' from the start whether its quantity rises, falls, or is kept steady, makes not the slightest difference; at the same time an extraneous element, in the shape of the supposed power of the banks to settle the way in which money is spent, has crept into the argument and has done all the work. As Volaire say you can kill a flock of sheep by incantations plus a little poison." Sraffa' acute criticism of Hayek for confining the role of money only to being a medium of exchange and equating implicitly a 'neutral' money economy with a non-monetary economy must be noted.

Sraffa, in connection with Hayek's criticism of Wicksell, also stressed the point that a 'non-monetary' economy could also be in disequilibrium, in contrat to Hayek's implicit notion that a divergence between the actual and the natural rate of interest is possible only in a monetary economy. Sraffa demonstrates that, in a barter economy, there could be as many natural rates of interest as there are commodities and each such rates will be equal to the equilibrium rate when the spot and forward prices coincide. Further, that "under free competition, this divergence of rates is essential to the effecting of this transition (to equilibrium) as is the divergence of prices from the costs of production" (p. 50). Sraffa also rejects Hayek's criticism of Wicksell that the natural rate of interest could not both keep the Price level stable and equate the demand and supply of capial in a growing economy. It is true that, in transition to a new equilibrium, there is no uique equilibrium rate of interest but a weighted average of natural rates can be suitably defined uing the same weights as for the general price level. This is, of necessity, not a unique average. In other words, there i for each composite commodity, a corresponding natural rate that can equalise purchasing power of savings and investment reckoned in terms of the composite commodity. Sraffa was also to point out that a non-monetary economy does not necessarily ensure a smooth transition to equilibrium through matching of savings and investment. Resources need to be matched and plans of consumers to save and investors to invest need to coincide so as to suitably direct resources from consumer goods to intermediate goods and vice versa. Sraffa's critique thus was important in clarifying the nature of the problem of money and in dispelling the pure monetarist arguments that all disequilibria situations are created by money whose operation is analysed purely in terms of an extraneous intervention. At thi juncture, we may note, Sraffa did not put out his critique of the Austrian treatment of 'capital' as period of production.

Ricardo volumes

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