Now, if it requires six hours to produce these goods, the laborer is producing surplus value if he labors more than that time. This the capitalist requires him to do, as he has hired his entire labor power. Under these circumstances, the laborer who works twelve hours a day for his employer is paid for six hours’ work, while he is robbed of the product of the other six hours’ labor. The capitalist is able to do this because he possesses the means of production. The laborer would gladly work without recourse to the capitalist, but he has not the means, the instruments with which to produce. He must accede to the terms of the capitalist or starve. The capitalist goes on the market and finds there the commodity, labor, for which he pays its value in exchange, as for any other commodity. But value in use does not depend upon value in exchange. The value in use of labor to the capitalist is all that he can squeeze out of it. The capitalist pockets the surplus value, and it becomes capital, enabling him to continue and enlarge his process of exploitation. Let the line, _a----b----c_, represent the labor of twelve hours, _b_ dividing it into two equal parts; _a----b_ is necessary labor; _b----c_ is unpaid labor productive of surplus value. It is the capitalist’s interest to extend _b----c_ as much as possible, as that governs his accumulations. Hence, the efforts of employers to increase the length of a day’s labor; hence, the efforts of employees to shorten _a--------c_, as they thereby diminish the amount of unpaid labor, of whose value they are robbed. This enables us to comprehend the significance of Marx’s definition of capital, which is as follows: “A negro is a negro. In certain relations he becomes a slave. A cotton-spinning-machine is a machine for spinning cotton. It becomes capital only in certain relations. Capital is a social relation existing in the processes of production. It is an historical relation. The means of production are not capital when they are the property of the immediate producer. They become capital only under conditions, in which they serve at the same time as the means of exploiting and ruling the laborer.... The foundation of the capitalistic method of production is to be found in that theft which deprived the masses of their rights in the soil, in the earth, the common heritage of all.”[177] That is to say, Marx limits the name capital to economic goods in the hands of employers.