Sraffa and the ‘slogans not used’

The two ‘slogans’ written by Sraffa in an early draft of the preface to his book (Sraffa Papers D3/12/43:1(3)) can be seen as the synthesis of a wider reasoning that he outlines in some manuscripts composed in 1955 and 1956. We rationalise this reasoning by three statements: A. The rate of profits manifests itself in the Standard system as the ratio of two well-defined quantities of Standard commodity; B. The rate of profits can be identified in the Standard system before knowing the prices of commodities; and C. The rate of profits emerging from the Standard system cannot be altered by ‘manipulations of prices’ and, for this reason, can be regarded as a non-price phenomenon. By discussing these statements in depth, we aim at shedding new light on the precise meaning of Sraffa’s slogans.