Solving the Reswitching Paradox in the Sraffian Theory of Capital By CARLO MILANA+ Birkbeck College, University of London Correspondence: Carlo Milana, Department of Management, Birkbeck College, Malet Street, Bloomsbury, London WC1E 7HX. Email:
[email protected] Fourth revision, 27th November 2019 Published in Applied Economics and Finance, Vol. 6, No. 6, November 2019 The possibility of the reswitching of techniques in Piero Sraffa’s intersectoral model, namely the recurring capital-intensive techniques with monotonic changes in the interest rate, is traditionally considered as a paradoxical violation of the assumed convexity of technology putting at stake the viability of the neoclassical theory of production. The purpose of this paper is to demonstrate that this phenomenon is rationalizable within the neoclassical paradigm. Sectoral interdependencies can give rise to the well-known Wicksell effect, which is the revaluation of capital goods due to changes in relative prices. The reswitching of techniques is, therefore, the result of cost-minimizing technical choices facing returning ranks of relative input prices in full consistency with the pure marginalist theory of factor rewards. The proposed theoretical analysis is applied empirically to revisit various numerical examples presented in the literature. Keywords: Capital theory, Neoclassical theory of production, Real factor-price frontier, Real wage-interest frontier, Reswitching of techniques, Reverse capital deepening, Sraffian critique of economic theory. JEL classification: B12, B13, B51, D33, D57, D61, Q11. 1. Introduction The use of the concept of marginal productivity in Piketty’s (2014) Capital in the Twenty-First Century has provoked a critical debate (including Galbraith, 2014 and Solow, 2014) drawing on the so-called Cambridge controversy of the 1960s and Piero Sraffa’s (1960) canonical book.