Page:Das Kapital (Moore, 1906).pdf/339

 of being extended from 6 to 9, is extended from 6 to 12 hours and at the same time variable capital is lessened by half, and reduced to 150s., it yields also a surplus-value of 150s. or 50×6 working hours. Diminution of the variable capital may therefore be compensated by a proportionate rise in the degree of exploitation of labour-power, or the decrease in the number of the labourers employed by a proportionate extension of the working-day. Within certain limits therefore the supply of labour exploitable by capital is independent. of the supply of labourers. On the contrary, a fall in the rate of surplus-value leaves unaltered the mass of the surplus-value produced, if the amount of the variable capital, or number of the labourers employed, increases in the same proportion.

Nevertheless, the compensation of a decrease in the number of labourers employed, or of the amount of variable capital advanced, by a rise in the rate of surplus-value, or by the lengthening of the working-day, has impassable limits. Whatever the value of labour-power may be, whether the working time necessary for the maintenance of the labourer is 2 or 10 hours, the total value that a labourer can produce, day in, day out, is always less than the value in which 24 hours of labour are embodied, less than 12s., if 12s. is the money expression for 24 hours of realized labour. In our former assumption, according to which 6 working hours are daily necessary in order to reproduce the labour-power itself or to replace the value of the capital advanced in its purchase, a variable capital of 1500s., that employs 500 labourers at a rate of surplus-value of 100% with a 12 hours’ working-day, produces daily a surplus-value of 1500s. or of 6500 working hours. A capital of 800s. that employs 100 labourers a day with a rate of surplus-value of 200% or with a working-day of 18 hours, produces only a mass of surplus-value of 600s. or 12×100 working hours; and its total value-product, the equivalent of the variable capital advanced plus the surplus-value, can, day in, day out, never reach the sum of 1200s. or 24×100 working hours.