Das Kapital

A precise distinction emerges here that runs through the rest of Volume 1: the difference between constant capital and variable capital. The means of production — raw materials, machines, buildings — transfer their value to the product but create no new value. The cotton enters the yarn; the spindle wears down; their value reappears in the finished product, neither more nor less. Marx calls this constant capital: its contribution to value is fixed in advance, passed along intact. Labour-power is different. When put to work, it not only replaces its own value (the wages paid) but generates an additional surplus. It is the one input whose use produces more than it cost. Marx calls it variable capital: it varies in value during the production process, expanding beyond its original magnitude. This distinction maps onto the dual character of labour established in Chapter 1. As concrete, useful labour — spinning, weaving, forging — the worker performs the specific operations that incorporate the value of raw materials and instruments into the new product. It is this concrete form that preserves and transfers existing value. As abstract human labour — the mere expenditure of human effort regardless of its form — the same act adds entirely new value to the product. These two effects happen simultaneously, in a single motion. The worker does not first preserve the cotton's value and then add new value; both happen at once, through one act. But they are analytically separable, and the separation matters. Constant capital, however large, cannot generate surplus value. A factory full of the most advanced machinery, with no living labour, produces nothing — the machines merely degrade. It is only variable capital, living labour-power, that makes the whole process expand. The practical implication: capitalists have a structural interest in increasing the ratio of living labour to dead capital, and later, in squeezing more surplus from each unit of variable capital. The distinction between c and v is not academic — it is the foundation of the rate of profit and the dynamics of accumulation.