Piero Sraffa’s physical price system and reproduction without production

Abstract

This article examines the physical price system of Piero Sraffa. Sraffa’s system is presented as a physical model of production, which provides an internally consistent and so logically superior alternative to Marx’s allegedly inconsistent labour theory of value. This article does not contest the internal consistency of Sraffa’s logic but demonstrates that its logic contradicts every actual process of production. Production, defined as the human labour process that transforms one set of physical inputs into a different set of physical outputs, is a process of physical change by definition, which in capitalist production means that outputs are physically incommensurate to, or different from, inputs. This article focuses on several key issues; commensurability, the standard commodity or physical numeraire; the relation between Sraffian and Leontief’s production matrix, including Quesnay’s Tableau Économique; and the production of surplus. It finds that Sraffa’s physical price system is not a model of production at all, it is a mathematically correct model of nothing. It is reproduction without production.