VIII. Production of Surplus Value
Now suppose that the average amount of the daily necessaries of a labouring man require six hours of average labour for their production. Suppose, moreover, six hours of average labour to be also realized in a quantity of gold equal to 3s. Then 3s. would be the price, or the monetary expression of the daily value of that man's labouring power. If he worked daily six hours he would daily produce a value sufficient to buy the average amount of his daily necessaries, or to maintain himself as a labouring man.
But our man is a wages labourer. He must, therefore, sell his labouring power to a capitalist. If he sells it at 3s. daily, or 18s. weekly, he sells it at its value. Suppose him to be a spinner. If he works six hours daily he will add to the cotton a value of 3s. daily. This value, daily added by him, would be an exact equivalent for the wages, or the price of his labouring power, received daily. But in that case no surplus value or surplus produce whatever would go to the capitalist. Here, then, we come to the rub.
In buying the labouring power of the workman, and paying its value, the capitalist, like every other purchaser, has acquired the right to consume or use the commodity bought. You consume or use the labouring power of a man by making him work, as you consume or use a machine by making it run. By buying the daily or weekly value of the labouring power of the workman, the capitalist has, therefore, acquired the right to use or make that labouring power during the whole day or week. The working day or the working week has, of course, certain limits, but those we shall afterwards look more closely at.
For the present I want to turn your attention to one decisive point. The value of the labouring power is determined by the quantity of labour necessary to maintain or reproduce it, but the use of that labouring power is only limited by the active energies and physical strength of the labourer. The daily or weekly value of the labouring power is quite distinct from the daily or weekly exercise of that power, the same as the food a horse wants and the time it can carry the horseman are quite distinct. The quantity of labour by which the value of the workman's labouring power is limited forms by no means a limit to the quantity of labour which his labouring power is apt to perform. Take the example of our spinner. We have seen that, to daily reproduce his labouring power, he must daily reproduce a value of three shillings, which he will do by working six hours daily. But this does not disable him from working ten or twelve or more hours a day. But by paying the daily or weekly value of the spinner's labouring power the capitalist has acquired the right of using that labouring power during the whole day or week. He will, therefore, make him work say, daily, twelve hours. Over and above the six hours required to replace his wages, or the value of his labouring power, he will, therefore, have to work six other hours, which I shall call hours of surplus labour, which surplus labour will realize itself in a surplus value and a surplus produce. If our spinner, for example, by his daily labour of six hours, added three shillings' value to the cotton, a value forming an exact equivalent to his wages, he will, in twelve hours, add six shillings' worth to the cotton, and produce a proportional surplus of yarn. As he has sold his labouring power to the capitalist, the whole value of produce created by him belongs to the capitalist, the owner pro tem. of his labouring power. By advancing three shillings, the capitalist will, therefore, realize a value of six shillings, because, advancing a value in which six hours of labour are crystallized, he will receive in return a value in which twelve hours of labour are crystalized. By repeating this same process daily, the capitalist will daily advance three shillings and daily pocket six shillings, one half of which will go to pay wages anew, and the other half of which will form surplus value, for which the capitalist pays no equivalent. It is this sort of exchange between capital and labour upon which capitalistic production, or the wages system, is founded, and which must constantly result in reproducing the working man as a working man, and the capitalist as a capitalist.
The rate of surplus value, all other circumstances remaining the same, will depend on the proportion between that part of the working day necessary to reproduce the value of the labouring power and the surplus time or surplus labour performed for the capitalist. It will, therefore, depend on the ratio in which the working day is prolonged over and above that extent, by working which the working man would only reproduce the value of his labouring power, or replace his wages.