In order to comprehend the problem in complete purity, Marx here assumes the whole of the surplus value to be capitalised, for which reason he ignores altogether that part of the surplus value is used for the capitalists' personal consumption; in addition, A´, A´´ and A´´´ as well as B´, B´´ and B´´´ here belong to Department I. 'The formation of a hoard, then, is not a production, nor is it an increment of production. The action of the capitalist consists merely in withdrawing from circulation 100 obtained by the sale of his surplus-product, in holding and hoarding this amount. This operation is carried on, not alone on the part of A, but at numerous points of the periphery of circulation by other capitalists named A´, A´´, A´´´.... However, A accomplishes the formation of a hoard only to the extent that he acts as a seller, so far as his surplus-product is concerned, not as a buyer. His successive production of surplus-products, the bearers of his surplus-value convertible into money, is therefore a premise for the formation of his hoard. In the present case, where we are dealing only with the circulation within Department I, the natural form of the surplus-product, and of the total product of which it is a part, is that of an element of constant capital of I, that is to say it belongs to the category of a means of production creating means of production. We shall see presently what becomes of it, what function it performs, in the hands of the buyers such as B, B´, B´´, etc. 'It must particularly be noted at this point that A, while withdrawing money from circulation and hoarding it, on the other hand throws commodities into it without withdrawing other commodities in return. The capitalists, B, B´, B´´, etc., are thereby enabled to throw only money into it and withdraw only commodities from it. In the present case, these commodities, according to their natural form and destination, become a fixed or circulating element of the constant capital of B, B´, etc.'[117] There is nothing new about this whole process. Marx had already described it extensively in connection with simple reproduction, since it alone can explain how a society is able to renew constant capital under conditions of capitalist reproduction. How this process can lay the besetting problem of our analysis of enlarged reproduction is far from self-evident. The difficulty had been that for the purpose of accumulation, part of the surplus value is not consumed by the capitalists but added to capital in order to expand production, giving rise to the question of buyers for this additional product. The capitalists do not want to consume it and the workers are not able to do so, their entire consumption being covered in every case by the available variable capital. Whence the demand for the accumulated surplus value? or, as Marx would have it: Whence the money to pay for the accumulated surplus value?