Das Kapital

A brief but mathematically exact argument unfolds here. Having established the rate of surplus-value (s/v), Marx now derives the mass of surplus-value — the total amount extracted across an entire workforce. The formula is simple: total surplus-value equals the surplus each worker produces multiplied by the number of workers employed. Double the workers, double the surplus. But this relationship operates within strict constraints, and Marx draws out three laws from it. First: the mass of surplus-value produced is jointly determined by the rate of exploitation and the amount of variable capital deployed. A capitalist can compensate a lower rate of exploitation with more workers, or squeeze a higher rate from fewer. These are alternative routes to the same surplus. Second: these routes have absolute limits. The rate of surplus-value cannot be pushed to infinity — there is a floor below which necessary labour cannot fall without the worker ceasing to reproduce their own labour-power. And the working day cannot exceed 24 hours. The capitalist who wants more surplus must either hire more workers or cheapen labour-power through rising productivity — options examined in the chapters that follow. Third, and most consequentially: below a certain minimum scale of capital, you cannot be a capitalist at all. You must employ enough workers that your own time is freed for supervision and coordination. The threshold varies historically, but the principle is fixed: capitalist production requires that the appropriation of others' surplus labour be the owner's primary activity, not a sideline. The chapter closes with a striking inversion. Labour, Marx notes, is consumed by capital — not the other way around. The worker enters the production process as a seller of labour-power and emerges as its residue, worn and expended. Capital presents this consumption as natural and mutual. Marx shows it is neither.