On the "logical necessity" of a uniform rate of profit in Sraffa's Production of Commodities by Means of Commodities

The paper discusses the analytical arguments put forward by Sinha to prove the purely «logical» necessity of a uniform rate of profit in Sraffa’s Production of Commodities by Means of Commodities and hence the independence of that condition from any consideration concerning competition. We find that such arguments cannot be accepted. In fact, far from establishing the existence of a contradiction that would be implied by unequal sectoral rates of profit, it is Sinha’s arguments that are self-contradicting. In particular, his main arguments are ultimately based on the idea according to which the average rate of profit of a given economic system is, and at the same time is not, independent from prices.