This lucid and comprehensive account is the best evidence that the problem is not just imaginary but very real. It provides a solution, not by disclosing a new 'source of money' for the realisation of the surplus value, but by pointing out at last the consumers of this surplus value. We are still, on Marx's assumption, within the bounds of simple reproduction; the capitalist class, that is to say, use the whole of their surplus value for personal consumption. Since the capitalists are the consumers of surplus value, it is not so much a paradox as a truism that they must, in the nature of things, possess the money for appropriating the objects of consumption, the natural form of this surplus value. The circulatory transaction of exchange is the necessary consequence of the fact that the individual capitalist cannot immediately consume his individual surplus value, and accordingly the individual surplus product, as could, for instance, the employer of slave labour. As a rule the natural material form of the surplus product tends to preclude such use. The aggregate surplus value of the capitalists in general is, however, contained in the total social product--as long as there is simple reproduction--as expressed by a corresponding quantity of consumer goods for the capitalist class, just as the sum total of variable capital has its corresponding equivalent in the quantity of consumer goods for the working class, and as the constant capital of all individual capitalists taken together is represented by material means of production in an equivalent quantity. In order to exchange the unconsumable individual surplus values for a corresponding amount of consumer goods, a double transaction of commodity exchange is needed: first, the sale of one's own surplus product and then the purchase of consumer goods out of the surplus product of society. These two transactions can only take place among members of the capitalist class, among individual capitalists, which means that their agent, the money, thereby merely changes hands as between one capitalist and another without ever being alienated from the capitalist class in general. Since simple reproduction inevitably implies the exchange of equivalents, one and the same amount of money can serve year by year for the circulation of the surplus value, and only an excess of zeal will inspire the further query: where does the money which mediates the capitalists' own consumption come from in the first place? This, question, however, reduces to a more general one: how did money capital initially come into the hands of the capitalists, that money capital of which they always retain a certain part for their personal consumption, apart from what they use for productive investment? Put in this way, however, the question belongs in the chapter of so-called 'primitive accumulation', i.e. the historical genesis of capital, going beyond the framework of an analysis of the