And he was then quite uncompromising about getting to the root of the matter: 'The circulating capital of 500 p.st. advanced in the form of money-capital, whatever may be its period of turn-over, may now stand for the total capital of society, that is to say, of the capitalist class. Let the surplus-value be 100 p.st. How can the entire capitalist class manage to draw continually 600 p.st. out of the circulation, when they continually throw only 500 p.st. into it?'[135] All that, mind you, refers to simple reproduction, where the entire surplus value is used for the personal consumption of the capitalist class. The question should therefore from the outset have been put more precisely in this form: how can the capitalists secure for themselves consumer goods to the amount of £100 surplus value on top of putting £500 into circulation for constant and variable capital? It is immediately obvious that those £500 which, in form of capital, always serve to buy means of production and to pay the workers, cannot simultaneously defray the expense of the capitalists' personal consumption. Where, then, does the additional money come from?--the £100 the capitalists need to realise their own surplus value? Thus all theoretical dodges one might devise for this point are summarily disposed of by Marx right away: 'It should not be attempted to avoid this difficulty by plausible subterfuges. 'For instance: So far as the constant circulating capital is concerned, it is obvious that not all invest it simultaneously. While the capitalist A sells 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 which A is just producing. The same transaction, which restores that of B to its productive form, transforms it from money into materials of production and labour-power; the same amount of money serves 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 referring to the quantity of the circulating money, which have been analysed in the circulation of commodities (vol. i, chap, iii), are in any way changed by the capitalist character of the process of production. 'Hence, when we have said that the circulating capital of society, to be advanced in the form of money, amounts to 500 p.st., we have already accounted for the fact 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 p.st., because it serves alternately as the money fund of different productive capitals. This mode of explanation, then, assumes that money as existing whose existence it is called upon to explain.