I The distinction between the turnover of commercial capital and that of industrial capital
As we have seen, the turnover of industrial capital is composed of the unity of production and circulation; it consequently embraces the entire process of production.
The turnover of commercial capital, on the other hand, is the movement of autonomous commodity capital, and, as such, represents the first phase in the commodity metamorphosis, C – M. The merchant buys, M – C, then sells, C – M in constant repetition. In circulation, the metamorphosis of industrial capital presents itself as C1 – M – C2: the money realised by the sale of C1 (the commodity product) is used to buy C2, new means of production. In this exchange of Cl – C2, the same money changes hands twice, mediating the exchange of two different kinds of commodities. The merchant’s case, however, is different: for her it is the same commodity that changes hands twice (in the movement M – C – M’) and it is now the commodity that mediates the reflux of money.
The number of turnovers of a given commercial capital is analogous to the repeated circuits of money as a simple means of circulation. Just as a given sum of money circulating ten times buys ten times its value in commodities, so the same money capital belonging to the merchant, say £100, will buy ten times its value in commodities, in other words realising a total commodity capital ten times its value, i.e. £1,000.
But there is also a difference. In the circulation of money, the same money passes through different hands; in the case of the merchant, however, the same money capital, independently of the money in which it consists, repeatedly buys and sells commodity capital, returning to the same owner as value plus surplus-value, i.e. as M + ΔM. It is in this sense that its turnover is a turnover of capital. More money is always withdrawn from circulation than is put in.
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