Class struggle is not, first and foremost, the struggle between classes, social classes, already constituted as such. Struggle is the ground of such social classes, be they working and owning classes or any other. It is this struggle which, situated within the organization of human activity as a whole (and the problematicity of this formulation does not for a moment escape me), comes before and allows for the genesis of social relations in which distinct classes take shape.
This struggle is a matter of force before relation, of a force at odds with itself, principally, the force of labor or work-force (the living). Class itself names this struggle, situated within the substructural organization of forces (an organization that is always difficult to maintain, always struggling to remain organized, and indeed, struggling to remain whole, to wholly encompass, and even to maintain the humanity of the whole, as humanity itself is but an effect of the organization of the productive activity of the living).
Class is struggle itself as constitutive, before it is a particular class that struggles with another, or even with itself. Thus the great difficult we face today in even identifying classes to which we or anyone might belong in terms of ownership of living or dead labor, the relative impossibility of doing so, and the real disarticulation of the division which engenders such impossibility, are constituted effects of a struggle that too often succeeds in effacing itself.
Classically (and whether there was a purely classical time is doubtful), classes were carved from the living, insofar as the general work-force was organized against itself. A part of this force subordinated the rest, by way of claiming exclusive right over the dead, the materialized past or means of production. This classical model degraded, whether it was ever really present or not (it is unimportant now), to the point that power was ascribed to dead labor itself, rather than its masters. Death (capital), now granted dominion over the living, becomes an “animated monster”, and all the more so in that the living increasingly become indistinguishable from the dead they slavishly serve. At this point, the work-force forgets the humanity it uses to distinguish itself just as it forgets the specificity of classes (workers and owners, not rich and poor; classes are replaced by a universal debtor class distinguished only by the health of their balance-sheets). It even forgets living itself, in forgetting ‘how to live’, or in other words, forgetting to ask itself ceaselessly ‘how to live?’ Death instead has already answered for it.
Classes are constituted (or not) in struggle. This is why Marx insists that the Proletariat must be organized as a class: the Proletariat is that exposure of work-force stripped bare of its humanity, of its situation within any constituted social relation, reduced to the quivering pulsations of an anxious and starved body. To organize that exposed, bare struggle itself as a class, rather than dissimulating it in a class that can clothe itself (even with difficulty), would be the undoing of class as a social relation that dissimulates struggle, but never of struggle itself. Rather, it would raise the struggle to exist – living – to the surface, as that which society can no longer deny. Together, this struggle is what we are, before we are even ourselves.
Everything existing struggles in doing so, and often, in order to do so as well; although, it is not unheard of that, in the struggle to cease existing, one only persists all the longer. This latter struggle is that of the Proletariat.