alike disregard constant capital in their exposition of reproduction, and it was Say in particular who presumed to perpetuate Adam Smith's confused concept of the aggregate product as _v + s_ as an unassailable dogma. The knowledge we owe to Marx that the aggregate product must, apart from consumer goods for the workers and capitalists (_v + s_), also contain means of production to renew what has been used, that accumulation accordingly consists not merely in the enlargement of variable but also of constant capital, is not enough, as amply demonstrated by this entertaining turn of events, to solve the problem of accumulation. Later we shall see how this stress on the share of constant capital in the reproductive process gave rise to new fallacies in the theory of accumulation. At present it will suffice to put on record that the deference to Smith's error about the reproduction of aggregate capital is not a weakness unique to Sismondi's position but is rather the common ground on which the first controversy about the problem of accumulation was fought out. Scientific research, not only in this sphere, proceeds in devious ways; it often tackles the upper storeys of the edifice, as it were, without making sure of the foundations; and so this conflict only resulted in that bourgeois economics took on the further complicated problem of accumulation without even having assimilated the elementary problem of simple reproduction. At all events, Sismondi, in his critique of accumulation, had indubitably given bourgeois economics a hard nut to crack--seeing that in spite of his transparently feeble and awkward deductions, Sismondi's opponents were still unable to get the better of him. FOOTNOTES: