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2.12.3 The modified general equilibrium approach

Coddington (1983) refers to this view as ‘reconstituted reductionism’

(reductionists are those economists whose method of analysis consists of

‘analysing markets on the basis of the choices made by individual traders’;

see Coddington, 1983, p. 92). This approach initially received stimulus from

Patinkin’s (1956) suggestion that Keynesian economics is the economics of

unemployment disequilibrium and that involuntary unemployment should be

viewed as a problem of dynamic disequilibrium. In Patinkin’s analysis, involuntary

unemployment can exist in a perfectly competitive economy with

flexible wages and prices. The emphasis given by Patinkin to the speed with

which markets are able to absorb and rectify shocks shifted attention away

from the degree of price and wage flexibility to the issue of coordination.

This line of enquiry was followed by Clower (1965) and Leijonhufvud (1968),

who developed a modified general equilibrium approach along Walrasian

lines in order to make sense of coordination problems which inevitably

emerge in a market economy operating without the fictional ‘auctioneer’. If

the hydraulic interpretation played down Keynes’s contribution as a theorist,

the reconstituted, reductionist approach attempts to rehabilitate the General

Theory as a pioneering exercise in disequilibrium dynamics.

Clower’s reinterpretation of the General Theory suggests that Keynes’s

revolt was against the Walrasian general equilibrium tradition within neoclassical

economics. In the Walrasian paradigm all markets continuously clear

thanks to the work of the fictional auctioneer. Building on the insights of

Patinkin (1956), Clower’s work emphasizes the dynamic disequilibrium nature

of Keynes’s work. Clower argues that Keynes’s objective was to kill off

the auctioneer myth in order to raise the profile of information and

intertemporal coordination difficulties within real economies. The cumulative

declines in output in Keynes’s General Theory result from massive coordination

failures as agents respond to wrong (false) price signals. Once the

assumption of instantaneously adjusted prices is abandoned there is no longer

any guarantee that a decentralized price system will coordinate economic

activity at full employment. Once again the classical model is shown to be a

‘special case’, and Keynes’s theory the more ‘general’ theory. Clower has

continued to be highly critical of all the mainstream macro schools for not

taking market processes seriously. To do so involves recognizing that markets

and monetary institutions are created by firms, individuals and governments.

In Clower’s view, in order to really understand market processes economists

need to create a ‘Post Walrasian Macroeconomics’ based on Marshallian

rather than Walrasian microfoundations (Clower and Howitt, 1996; Colander,

1996). While Keynes had a profound influence on the development of macroeconomics,

his anti-formalist approach was swept away by the ‘Walrasian

formalism’ of mainstream theorists in the post-1945 period (Backhouse,

1997a).

In the 1970s several economists inspired by Clower’s insights went on to

develop neo-Keynesian quantity-constrained models (Barro and Grossman,

1976; Malinvaud, 1977). This work served to remind economists that conventional

Keynesian models lacked solid microfoundations (Barro, 1979). This

was a theme the new classical economists were to exploit throughout the

1970s but in a very different way from that favoured by Clower. During the

1970s the new classical approach prospered while the neo-Keynesian models

gradually fell out of favour, not least because high inflation made fix-price

models appear ‘unrealistic’ (Backhouse, 1995).

In the mid to late 1960s, Axel Leijonhufvud also provided an influential

and provocative interpretation of Keynes’s General Theory. His dissertation

thesis, On Keynesian Economics and the Economics of Keynes, was an instantaneous

success when published in 1968 and became the subject of

intense debate and controversy given its novel analysis of Keynes’s most

influential contribution. Leijonhufvud elaborates upon the Clower theme by

building an ‘economics of Keynes’ that is distinct from the Walrasian

Keynesianism that characterizes the mainstream neoclassical synthesis interpretation.

Leijonhufvud, following Patinkin (1948), provides a neo-Walrasian

interpretation of Keynes which focuses on the process and implications of

disequilibrium trading and coordination failure. In doing so, Leijonhufvud

shows how Keynes’s (1936, p. 15) concept of ‘involuntary unemployment’

emerges as a dynamic disequilibrium phenomenon. In Leijonhufvud’s reinterpretation

of the General Theory, Keynes’s main innovation is seen to be

his attempt at providing a coherent and systematic analysis of how a predominantly

private enterprise market economy reacts, responds and adjusts in

the short run to aggregate demand shocks when price and wage adjustments

are less than perfectly flexible. The Walrasian assumptions of instantaneous

price and wage flexibility and complete information are nothing more than a

fiction. Leijonhufvud therefore argues that Keynes provided a more General

Theory where the incomplete information of agents prevents the economic

system from moving quickly and smoothly to a new equilibrium following an

aggregate demand shock. Leijonhufvud’s reinterpretation of Keynes attempts

to show that the content of the General Theory is consistent with a choicetheoretic

framework providing the key assumption, that agents have complete

information when trading, is abandoned. There is no need to resort to imposing

institutional rigidities (such as rigid nominal wages) on the price

mechanism to generate Keynesian outcomes. This is a direct refutation of the

‘Keynesian Gospel According to Modigliani’ (2003). The late Nobel Memorial

Laureate Franco Modigliani (2003) continued to maintain that ‘the essence

of Keynesian economics is wage rigidity. That is Keynes’ (see the interview

with Modigliani in Snowdon and Vane, 1999b, and Chapter 3).

Leijonhufvud suggests that the neoclassical synthesis interpretation of

Keynes provides an incoherent theoretical basis for a Keynesian revolution.

He argues that Keynes recognized the difficulties experienced, within decentralized

market economies, of finding the appropriate market-clearing price

vector. In Keynes’s vision, the initial response to shocks on the system is via

quantity adjustment rather than price adjustment, with the relative speed of

adjustment of the latter tending to lag behind the former (a reversal of the

Walrasian approach). In the absence of the fictional ‘Walrasian auctioneer’,

the key issue focuses on the control mechanisms and relates to the generation

and dissemination of information. According to Leijonhufvud, the information

and coordination deficiencies lead to deviation-amplifying (positive

feedback) processes, such as the multiplier, which were played down by the

Walrasian synthesis which highlighted the deviation-counteracting (negative

feedback) mechanisms.

Leijonhufvud argues that the neoclassical synthesis totally misunderstands

and misinterprets Keynes (Leijonhufvud, 1981; Snowdon, 2004a). The orthodox

Keynesian story highlights elements that play no real part in the argument

of the General Theory (but a significant part in the work of the Keynesians) –

such as the claims that wages are rigid; that the liquidity trap exists in

actuality; and that investment is interest-inelastic. Leijonhufvud controversially

maintains that none of these essential Keynesian building blocks is to

be found in the economics of Keynes (see Chapter 3).

After the initial enthusiasm and wide interest that Leijonhufvud’s interpretation

of Keynes aroused during the 1970s, the younger generation of

economists were soon caught up in the excitement created by the ‘rational

expectations’ revolution inspired by Robert Lucas (see Chapter 5). Interest in

Keynes and Keynesian economics began to wane. By his own admission

Leijonhufvud (1993) ‘drifted out of the professional mainstream from the

mid-1970s onwards, as intertemporal optimisation became all the rage’. As

Leijonhufvud (1998a) recalls, ‘macroeconomics seemed to have taken a turn

very similar to the movies: more and more simple-minded plots but ever

more mind-boggling special effects. One would like to look forward to a

macroeconomics whose plots will give more insight into the human condition.’

While the younger generation of new classical economists was

everywhere pronouncing the end of the Keynesian era and embracing rational

expectations and equilibrium theories of the business cycle, Leijonhufvud

has continued to argue that Keynesian economics has a future. Leijonhufvud

(1992) suggests two main reasons for such optimism. First, the coordination

problem is too important an issue to be kept indefinitely off economists’

research agenda. ‘Will the market system “automatically” coordinate economic

activities? Always? Never? Sometimes very well, but sometimes pretty

badly? If the latter, under what conditions, and with what institutional structures,

will it do well or do badly?’ Leijonhufvud regards these questions as

the central ones in macroeconomics. Second, Leijonhufvud believes that

sooner or later economists must open up their theoretical structures to allow

results from other behavioural sciences to be utilized in economic analysis.

When that happens, ‘the “unbounded rationality” postulate will have to go’.

In his Nobel Memorial Lecture, George Akerlof (2002) also presents a

strong case for strengthening macroeconomic theory by incorporating assumptions

that take account of behaviour such as ‘cognitive bias, reciprocity,

fairness, herding and social status’. By doing so Akerlof argues that macroeconomics

will ‘no longer suffer from the “ad hockery” of the neoclassical

synthesis which had overridden the emphasis in the General Theory on the

role of psychological and sociological factors’. Since in Akerlof’s view

Keynes’s General Theory ‘was the greatest contribution to behavioural economics

before the present era’, it would seem that economists need to

rediscover the ‘wild side’ of macroeconomic behaviour in order to begin the

construction of ‘a not too rational macroeconomics’ (Leijonhufvud, 1993).

The interested reader is referred to Chapter 3, section 3.5 (and references

therein) of Snowdon, et al. (1994), for a more detailed discussion of the work

of Clower, Leijonhufvud and Malinvaud.