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128 Piero SraffaSraffa raised against the Marshallian theory of the firm (contradictionbetween the hypothesis of competition and the ceteris paribus hypothesistypical of partial equilibria) are sometimes said to hold in relation topartial equilibrium analysis, but to be irrelevant to ‘truly general’ analysis,which is the only analysis legitimate for the pure theoretician. 22Much the same evaluation is advanced with regard to the ‘Cambridge’criticism of the aggregate concept of capital, merely conceived as a simplifiedparabola, a ‘low level theory’ compared to the ‘true’ theory, i.e.,general equilibrium. 23In every field of science the idea that a general, all-embracing theoryis superior to ‘partial’ theories has shown its appeal. The problemhere – at least as far as the marginalist approach is concerned – is thatwe must sacrifice to the fetish of a general theory, either rigour (in thecase of ‘parables’) or relevance (since the theory of general equilibriumprovides scant heuristic scope, once the multiplicity and possible instabilityof equilibriums are granted, and has nothing to do with the realworld once we recognise the need for hypotheses on the convexity ofproduction and consumption sets, corresponding to the hypothesis ofgeneralised decreasing returns for production and consumption alike).This is no new problem. It has been addressed on various occasions inthe philosophical and epistemological debate, and it is worth recallingthat, thanks to his influence on Wittgenstein, Sraffa played a veryimportant role in this field too.As mentioned earlier (§ 2.2), Wittgenstein’s change of views, whichtook place under Sraffa’s influence, can be seen in the light of comparisonbetween the methodology of general economic equilibrium analysisand a methodology of distinct and separate pieces of analysis, which inour interpretation underlies Sraffa’s approach.Let us recall Wittgenstein’s (1921) initial view, based on a correspondencebetween the ‘facts’, constituting the world, and ‘propositions’,constituting our image of the world, so that we can describe the world22Cf. Samuelson (1987: 458–9); Newman and Vassilakis (1988). Actually, asalready stressed earlier (§ 1.3), the criticisms posed by Sraffa in the articles of1925 and 1926 are far more radical, regarding the very foundations of any analysisbased on functional relationships between cost and quantities produced andthe hypothesis of the convexity of production sets.23In reality the ‘Cambridge’ criticisms only initially concerned the aggregateconcept of capital (Robinson 1953); after the publication of Sraffa’s book (andof Garegnani 1960) the emphasis shifted to the concept of capital as a factor ofproduction (and, correlatively, to the notion of profit as the price for the serviceof this factor of production). Cf. Chapter 6.Interpreting Production of Commodities 129with a set of propositions, each one describing a ‘fact’. The set of all ‘true’propositions constitutes, in a sense, our general theory of the world; onlywhat cannot be the object of such a representation (‘the unspeakable’) isexcluded from our rational representation of the world.The marginalist theory of general economic equilibrium seems to befounded on philosophical positions much like those (‘analytical positivism’)of this early Wittgenstein: an atomist base (‘economic subjects’and ‘commodities’), correspondence between the facts of the world andthe elements of theory, the claim of a complete description according togeneral rules regarding all that is describable in the world (the generaltheory). 24As we saw earlier (§ 2.2), Wittgenstein (1953) eventually abandonedhis initial views and developed instead the idea of ‘language games’,namely models that focus attention on particular aspects of real language.A commentator interpreted it this way:There is not […] any unique analysis of propositions into their intrinsicallyunanalysable elements. What sort of analysis will be usefuland provide a real clarification depends on the circumstances, on justwhat is problematic about the propositions under examination. 25Of course, this is not to say that having criticised the early stages ofWittgenstein’s reflections Sraffa then went on to endorse his point ofarrival. Nevertheless, we can see a distinct analogy with the methodSraffa follows in his book, focusing on a specific problem (fundamental24As a matter of fact, most marginalist theorists – though by no means all –explicitly or implicitly adopt a somewhat less refined version of positivism, theso-called ‘received view’ (cf. Caldwell 1982). In a nutshell, the idea is that scientistswork by applying the methods of logical analysis on the raw material providedby empirical experience. To evaluate their results, objective criteria for acceptanceor rejection can be established. More precisely, analytic statements, namelythose concerning abstract theoretical reasoning, are either tautological, that is,logically implied in the assumptions, or self-contradictory, that is, they containlogical inconsistencies; in the former case, the analytic statement is accepted,in the latter rejected. Similarly, synthetic statements, namely those concerningthe empirical world, are either confirmed or contradicted by the evidence, andhence accepted or rejected for objective reasons. All other statements for whichno analogous criteria of acceptance or rejection can be found are termed metaphysicaland are considered external to the field of science. This implies, however,that the set of analytic statements and the set of synthetic statements are keptcompletely separate; quite simply, economic research, in the sense of endeavourto understand the world in which we live, does not work in this way.25Quinton (1968: 12–3).