In all purchases and sales of commodities -- so far as only these transactions are under discussion -- it is quite immaterial what becomes of the proceeds the seller receives for his commodities, and what becomes of the bought articles of use in the hands of the buyer. Hence, so far as the mere process of circulation is concerned, it is quite immaterial that the labour-power bought by the capitalist reproduces capital-value for him, and that on the other hand the money received by the labourer as the purchase-price of his labour-power constitutes his revenue. The magnitude of value of the labourer's article of commerce, his labour-power, is not affected either by its forming "revenue" for him or by the fact that the use of this article of commerce by the buyer reproduces capital-value for this buyer.
Since the value of labour-power -- i.e., the adequate selling price of this commodity -- is determined by the quantity of labour required for its reproduction, and this quantity of labour itself is here determined by that needed for the production of the necessary means of subsistence of the labourer, hence for the maintenance of his existence, the wages become the revenue on which the labourer has to live.
It is entirely wrong, when Adam Smith says (p. 223): " That portion of the stock which is laid out in maintaining productive hands ...
after having served in the function of a capital to him [the capitalist]
... constitutes a revenue to them" [the labourers]. The money with which the capitalist pays for the labour-power purchased by him "serves in the function of a capital to him," since he thereby incorporates labour-power in the material constituents of his capital and thus enables his capital to function altogether as productive capital. We must make this distinction:
The labour-power is a commodity , not capital, in the hands of the labourer, and it constitutes for him a revenue so long as he can continuously repeat its sale; it functions as capital after its sale, in the hands of the capitalist, during the process of production itself. That which here serves twice is labour-power: as a commodity which is sold at its value, in the hands of the labourer; as a power-producing value and use-value, in the hands of the capitalist who has bought it. But the labourer does not receive the money from the capitalist until after he has given him the use of his labour-power, after it has already been realised in the value of the product of labour. The capitalist possesses this value before he pays for it. Hence it is not the money which functions twice:
first, as the money-form of the variable capital, and then as wages. On the contrary it is labour-power which has functioned twice: first, as a commodity in the sale of labour-power (in stipulating the amount of wages to be paid, money acts merely as an ideal measure of value and need not even be in the hands of the capitalist); secondly, in the process of production, in which it functions as capital , i.e., as an element, in the hands of the capitalist, creating use-value and value. Labour-power already supplied, in the form of commodities, the equivalent which is to be paid to the labourer, before it is paid by the capitalist to the labourer in money-form. Hence the labourer himself creates the fund out of which the capitalist pays him. But this is not all.
The money which the labourer receives is spent by him in order to preserve his labour-power, or -- viewing the capitalist class and the working-class in their totality -- in order to preserve for the capitalist the instrument by means of which alone he can remain a capitalist.
Thus the continuous purchase and sale of labour-power perpetuates on the one hand labour-power as an element of capital, by virtue of which the latter appears as the creator of commodities, articles of use having value, by virtue of which, furthermore, that portion of capital which buys labour-power is continually restored by labour-power's own product, and consequently the labourer himself constantly creates the fund of capital out of which he is paid. On the other hand the constant sale of labour-power becomes the source, ever renewing itself, of the maintenance of the labourer and hence his labour-power appears as that faculty through which he secures the revenue by which he lives. Revenue in this case signifies nothing else than a appropriation of values effected by ever repeated sales of a commodity (labour-power), these values serving only for the continual reproduction of the commodity to be sold. And to this extent Smith is right when he says that the portion of the value of the product created by the labourer himself for which the capitalist pays him an equivalent in the form of wages, becomes the source of revenue for the labourer. But this does not alter the nature or magnitude of this portion of the value of the commodity any more than the value of the means of production is changed by the fact that they function as capital-values, or the nature and magnitude of a straight line are changed by the fact that it serves as the base of some triangle or as the diameter of some ellipse. The value of labour-power remains quite as independently definite as that of those means of production.