In Marx’s analysis, social domination in capitalism does not, on its most fundamental level, consist in the domination of people by other people, but in the domination of people by abstract social structures that people themselves constitute. Marx sought to grasp this form of abstract, structural domination­ — which encompasses, and extends beyond, class domination — with his categories of the commodity and capital. This abstract domination not only determines the goal of production in capitalism, according to Marx, but its material form as well. Within the framework of Marx’s analysis, the form of social domination that characterizes capitalism is not ultimately a function of private property, of the ownership by the capitalists of the surplus product and the means of pro­duction; rather, it is grounded in the value form of wealth itself, a form of social wealth that confronts living labor (the workers) as a structurally alien and dom­inant power.

Moishe Postone, Time, Labor, and Social Domination (1993)

The real wealth of society and the possibility of a constant expansion of its reproduction process does not depend on the length of surplus labour but rather on its productivity and on the more or less plentiful conditions of production in which it is performed. The realm of freedom really begins only where labour determined by necessity and external expediency ends; it lies by its very nature beyond the sphere of material production proper. [...]

This realm of natural necessity expands with [man's] development, because his needs do too; but the productive forces to satisfy these expand at the same time. Freedom, in this sphere, can consist only in this, that socialized man, the associated producers, govern the human metabolism with nature in a rational way, bringing it under their collective control instead of being dominated by it as a blind power; accomplishing it with the least expenditure of energy and in conditions most worthy and appropriate for their human nature. But this always remains a realm of necessity. The true realm of freedom, the development of human powers as an end in itself, begins beyond it, though it can only flourish with this realm of necessity as its basis.

Karl Marx, Capital: Critique of Political Economy, Volume 3 (The Trinity Formula), Fernbach translation