## Friday, 31 March 2017

### Theories of Surplus Value, Part I, Chapter 4 - Part 25

Suppose, Marx says, we take a coal mine, iron works, timber producer and machine builder. The constant capital of each is equal to a third, so that it relates to the new value produced by labour as 1:2.

“Then all these industries produce each a daily product of x, x', x'', x'''.” (p 188)

Let us say these quantities are 120,150,180,210 of whatever unit may be appropriate, such as tons of coal, iron and timber and number of machines. This is the quantity produced by labour in a day, in each case, but this product is not just the product of labour. The coal producer, to achieve their output, will have used some of their own coal to power steam engines, which themselves will have been bought from the machine maker, and they will have used wood and iron for pit props and so on.

In other words, a third of the value of their output is due to the value of this constant capital used in its production. Put in terms of the use values produced, of the 120 tons of coal produced, 40 tons is simply due to to the constant capital used in its production, and 80 tons are due to the day's labour employed in its production. If we think about it in terms of that used at the beginning, where the coal producer provides coal to the steel producer, and the steel producer provides steel to the coal producer of equal value, it is as though, here the coal producer gives an amount of coal to the steel producer, wood producer and machine maker, and obtains an equal value of steel, wood and machines in return, and thereby reproduces the constant capital consumed in the day's coal production.

It is as though the coal producer took 40 tons of coal directly out of their production and used it themselves as constant capital, leaving just 80 tons available for sale. The only difference here is that instead of taking out 40 tons of coal and using it as constant capital, to replace the coal they have consumed fuelling their steam engines, they instead obtained the constant capital in another physical form – steel, wood, machines.

But, each of the other producers did exactly the same thing. A third of the steel producer's output is equally attributable to their constant capital – 50 tons – so that only 100 tons are actually available for sale. Rather like a farmer takes a proportion of their wheat, simply to obtain the seed required to replace that used to grow this year's crop, so here, it is as though the coal producer and steel producer take a proportion of their output simply to replace their own constant capital, thereby removing it from what is available for sale.

The steel producer may require some of their output simply to replace steel they have used themselves, just as the coal miner used some of their output to replace coal used to power their steam engines. But, whether this is the case or not, is irrelevant, because the fact remains that each of these producers sets aside a third of their output simply to replace the constant capital consumed in its production, whether it takes the form of their own output or that of some other producer.