For instance: So far as the constant circulating capital is concerned, it is obvious that not all invest it simultaneously. While capitalist Asells his commodities, so that his advanced capital assumes the form of money, there is on the other hand the available money-capital of the buyer B which assumes the form of his means of production -- precisely what Ais producing. By the same act through which A restores the money-form to his produced commodity-capital, B returns his capital to its productive form, transforms it from money-form into means of production and labour-power;the same amount of money functions in the two-sided process as in every simple purchase C---M. On the other hand when A reconverts his money into means of production, he buys from C, and this man pays B with it, etc., and thus the transaction would be explained. But:
None of the laws established with reference to the quantity of the circulating money in the circulation of commodities (Buch I, Kap. III), [English edition: Ch. III. -- Ed .] are changed in any way by the capitalist character of the process of production.
Hence, when one says that the circulating capital of society to be advanced in the form of money amounts to £500, one has already taken into account that this is on the one hand the sum simultaneously advanced, and that on the other hand it sets in motion more productive capital than £500 because it serves alternately as the money-form of various productive capitals. This manner of explanation, then, assumes the money, whose existence it is called upon to explain, as already existing.
It might be further said: Capitalist A produces articles which capitalist B consumes individually, unproductively. B's money therefore turns A's commodity-capital into money and thus the same sum of money serves to realise B's surplus-value and A's circulating constant capital. But in that case the question that still awaits solution is assumed still more directly to have been solved, namely: where does B get the money that makes up his revenue? How did he himself realise this portion of the surplus-value of his product?
It might also be said that the part of the circulating variable capital which A steadily advances to his labourers returns to him steadily from the circulation, and only a varying part of it always stays with him for the payment of wages. But a certain time elapses between the expenditure and the reflux, and meanwhile the money paid out for wages might, among other uses, serve for the realisation of surplus-value.
But we know in the first place that the longer this time the greater must be the supply of money which capitalist A must keep constantly in petto . In the second place the labourer spends the money, buys commodities for it and thus converts into money pro tanto the surplus-value contained in them. Consequently the same money that is advanced in the form of variable capital serves pro tanto also the purpose of turning surplus-value into money. Without penetrating any further into the question at this point, let this suffice: the consumption of the entire capitalist class and its retainers keeps step with that of the working-class; hence simultaneously with the money thrown into circulation by the labourers the capitalists too must throw money into it, in order to spend their surplus-value as revenue. Hence money must be withdrawn from circulation for it. This explanation would serve merely to reduce, but not eliminate, the quantity of money required.
Finally, it might be said: A large amount of money is constantly thrown into circulation when fixed capital is first invested, and it is recovered from the circulation only gradually, piecemeal, after a lapse of years, by him who threw it into circulation. Cannot this sum suffice to convert the surplus-value into money?
The answer to this must be that perhaps the sum of £500(which includes hoard formation for needed reserve funds) implies its employment as fixed capital, if not by him who threw it into circulation, then by somebody else. Besides, it is already assumed in regard to the amount expended for the procurement of products serving as fixed capital that the surplus-value contained in them is also paid, and the question is precisely where this money comes from.
The general reply has already been given: If a mass of commodities worth x times £1,000 has to circulate, it changes absolutely nothing in the quantity of the money required for this circulation whether the value of this mass of commodities has been produced capitalistically or not. The problem itself therefore does not exist. All other conditions being given, such as velocity of the currency of money, etc., a definite sum of money is required in order to circulate commodities worth x times £1,000 quite independently of how much or how little of this value falls to the share of the direct producers of these commodities. So far as any problem exists here, it coincides with the general problem: Where does the money required for the circulation of the commodities of a country come from?