Outside the office, the worker does not stop working but enters a different phase of the same process. This is one capital has no interest in supervising yet upon which the entire edifice of production depends: the reproduction of labour-power. This is the background hum of capitalist accumulation, the thing capital can safely assume will happen because hunger and shelter and exhaustion enforce their own deadlines, and because the system has arranged that no alternative exists but to show up again tomorrow.

Labour-power is not a thing one possesses like a tool; it is the capacity of a living human being to transform the world, and its value is the labour-time socially necessary to bring that capacity into existence and maintain it day after day. Marx names this directly in the sixth chapter of Capital, where he writes that labour-power “exists only as a capacity, or power of the living individual,” and that “its production consequently pre-supposes his existence,” then adding that “for his maintenance he requires a given quantity of the means of subsistence.” That quantity is not a natural fact but a battleground: what counts as subsistence is “the product of historical development,” varying with climate, civilisation, and the established habits of a class, which is to say, varying with the balance of forces between those who sell their capacity to work and those who buy it.

So the worker goes home, eats, sleeps, perhaps buys something to wear, keeps a roof of some description over their head, pays for the upkeep of children who will one day sell their own labour-power to the same or a different buyer, and might even acquire a skill that commands a slightly higher wage. Every one of these activities is, from the standpoint of capital, an act of production, i.e. the production and reproduction of the living labour-machine without which surplus value cannot be extracted. Marx is careful to note that capital may safely leave this work to “the worker’s drives for self-preservation and propagation,” which is a way of saying that capital does not pay for reproduction out of generosity but because the alternative is the extinction of the working class and the collapse of the system itself. The wage covers the cost of subsistence, not the cost of life; life is simply the substrate upon which subsistence is calculated.

The structural violence of wage labour becomes most visible here, if we are willing to look at the hours that are not on the clock. The capitalist pays for labour-power during the working day, but the worker spends their evenings and weekends—their “free time”—restoring what the working day consumed: muscle, nerve, brain, attention, patience. That restoration is labour, unpaid and unrecognised, classified as private life and therefore nobody’s business but their own, yet without it production stops. The system has externalised the cost of its own maintenance onto the worker’s time and body so thoroughly that we no longer even perceive it as an externalisation but simply as life. Sleeping is not work, we say, and in one sense this is obviously true. But sleeping is the condition of possibility for tomorrow’s work, and the worker who cannot sleep because the rent is too high or the room too crowded or the shift pattern too erratic will nevertheless be held responsible for their diminished output the next morning.

Reproduction includes a generational dimension that extends beyond daily meals into the long arc of class continuity. Labour-power does not renew itself spontaneously from one generation to the next without material conditions of child-rearing, feeding, housing, and education. And moreover, in the advanced capitalist societies, increasingly without debt, credentialing systems, and the intergenerational transfer of the costs of skill formation from capital back onto families. What appears as “human capital investment” from the perspective of neoclassical economics is, from a materialist standpoint, the displacement of reproduction costs onto the worker and their kin, subsidised by unwaged care work disproportionately performed by women, and then celebrated as opportunity.

We should be clear about what Marx is not saying here. He is not saying that capital has a plan, or that capitalism is stable, or that the reproduction of labour-power always succeeds. He is describing a tendency, a structural logic, the material foundation upon which the superstructure of wage bargaining and labour law and welfare policy is erected. The system requires that workers be reproduced at a certain level but does not directly control the household. Rather, it simply withholds the means of subsistence unless reproduction occurs. The worker must eat, therefore the worker must work; because the worker must work, they must also continue to exist; because they must continue to exist, some portion of the wage must be spent on the activities that make existence possible; and because that portion is determined by a historical and moral standard that capital constantly tries to drive downward, the entire terrain of daily life becomes a site of class struggle over what counts as necessary.

Understood in this light, the day-to-day activities outside of work are not merely rest or leisure or consumption but unpaid, dispersed, unorganised, and absolutely indispensable. Cooking a meal, washing a uniform, commuting, recovering from an injury, calming a child who cannot sleep because the walls are thin and the neighbours are arguing, sitting in a waiting room with a healthcare card that covers less than it used to: all of these are moments in the reproduction of labour-power, systematically occluded from the accounting of value. Capital measures the working day but does not measure the night, and the night is where the working day is made possible again. The worker who cannot repair themselves will not be a worker for long, and capital knows this instinctively. Which is why it has never been indifferent to housing policy, food prices, healthcare, or the length of the commute. This isn’t because capital cares about well-being, but because the reproduction of labour-power has a cost, and capital wants that cost borne by someone else.

That someone else is us—the workers, the households, the informal economies of care and repair that keep the whole apparatus from seizing up. We call it life, our personal time, our private choices, our individual responsibilities. We do not call it what it is: the unpaid labour of reproducing the working class, without which the paid labour of the working day could not happen and the extraction of surplus value would grind to a halt on Monday morning.

To name this is not to say that eating or sleeping or caring for others should be abolished, but to say that when we describe the economy we usually describe only the part that happens under supervision, within working hours, for a wage. But yet remains the vast, invisible, unremunerated rest we call the background, treating it as though it were naturally occurring rather than produced. The background is produced, by us, in the hours when capital is not watching, under conditions we did not choose, at costs we bear alone, for a system that would collapse if we stopped. That is the material condition of the reproduction of labour-power, and until we refuse the distinction between the work that is counted and the work that is merely lived, we will keep mistaking the office for the whole of production and the wage for the whole of value.