Introduction

Marx considered his analysis of “the tendency of the profit rate to fall as society progresses” to be “one of the greatest triumphs over the pons asini of all previous political economy” (letter to Engels, 30 April 1868; in MECW 43: 24). He clarifies in his letter that “[t]his already follows from what was developed in Book I [MECW 35: 616–23] on the change in the composition of capital with the development of the social productive power.” And in fact we shall see that Capital 1 is explicit enough about the matter (MECW 35: 309–10; below, p. 121). It has been argued that Marx in fact abandoned his analysis of the downward secular trend between writing the material that appeared in Capital 3 and which dates to 1864–65 (see Introduction, above, pp. 3–4), and publishing his Capital 1 in 1867 (Groll and Orzech 1987). But the letter to Engels suggests there was no such abandonment; certainly Engels insisted to the end on the downward secular trend as an essential feature of Marx's doctrine (e.g., Preface to Capital 3, dated 4 October 1894; MECW 37: 23). And the passage I shall cite from Capital 1 confirms the point. (See also Fine 1990: 154.)

In Capital 3, Chapter 13, on “The Law as Such” the trend is represented as “a logical necessity” flowing from “the nature of the capitalist mode of production” (MECW 37: 209).