Recht vs. an ethics of emancipation. For Marx the ideology of equivalence and right--of free informed owners or juridical subjects trading equivalent for equivalent--is not a mere a superstructure but intrinsic to the process through which appropriation or exploitation dis-simulates itself. But can we tease out an ethic of emancipation independent of and in contradiction to moral and legal ideology, the ideology of Recht, Steven Lukes asked long ago? That's one question.
The already implicit question however revolves around why extant morality provides no basis for immanent criticism of capitalist exploitation; on the contrary. It's not that Marx does not think exploitation is not immoral; it's that he does not think it can be shown in capitalist society. Why? That's the difficult question.
Marx emphasizes that the subject who is exploited is not a worker, qua an individual, as the individual worker is usually paid in full for the value what he exchanges, labor power. Nothing immoral here.
However if one looks at the system macroeconomically and dynamically, it becomes apparent that the value which individual workers are paid is value already appropriated, taken without equivalent not so much from this individual worker but workers in general. That is, the capitalist class may act morally and respect the law of exchange with individual workers but they are violating them in their relations with the working class a whole. That relation has long been turned under repeated exchanges into one of appropriation, i.e. the opposite of an exchange relation. Capitalists are only giving what they had already appropriated. This is not exchange among free and equal commodity owners. Once actual content is considered, the exchange relationship is indeed in violation of the basic codes of society.
But the generalization of commodity exchange requires that we be interpellated as autonomous individual subjects, wear the masks of juridical subjects. I refer here not to fundamental ontology in a Heideggerian sense (being whose being is a question for it) but the rather more pedestrian social ontology. And collective subjects can't be recognized as concrete individuals who could say WE have not been treated in accordance with the laws and codes of exchange, the basis of bourgeois morality and law.
As Marx writes; "To be sure, the matter looks quite different if we consider capitalist production in the uninterrupted flow of its renewal, and if, in place of the individual capitalist and the individual worker, we view in their totality, the capitalist class and the working-class confronting each other. But in so doing we should be applying standards entirely foreign to commodity production."
The collective subject has no place in noisy marketplace, the Eden of innate rights of Man, freedom, equality, property and Bentham.
Morality then is conservative not so much because of its logic of equivalence (Marx certainly sees its limits but does accede to it as distributional principle in early socialism so he's not the equality hater Nietzsche was) but because of its inherent individualism or humanism as Althusser would have put it.
For this reason, Marx's critique of morality is quite different from Nietzsche's. And Marx's anti individualism is quite different from Nietzsche's. Marx's critique is hardly likely to appeal to those who can already project their power as individuals or--more schizophrenically--as multiple selves within the same individual. He speaks to those for whom power can only be exercised through organized collective power from below.
Hard to imagine Niezsche friend, rather than foe.
Here is some of Marx from chapter 24 Capital I:
in so far as each single transaction invariably conforms to the laws of the exchange of commodities, the capitalist buying labour-power, the labourer selling it, and we will assume at its real value; in so far as all this is true, it is evident that the laws of appropriation or of private property, laws that are based on the production and circulation of commodities, become by their own inner and inexorable dialectic changed into their very opposite. The exchange of equivalents, the original operation with which we started, has now become turned round in such a way that there is only an apparent exchange. This is owing to the fact, first, that the capital which is exchanged for labour-power is itself but a portion of the product of others' labour appropriated without an equivalent; and, secondly, that this capital must not only be replaced by its producer, but replaced together with an added surplus. The relation of exchange subsisting between capitalist and labourer becomes a mere semblance appertaining to the process of circulation, a mere form, foreign to the real nature of the transaction, and only mystifying it. The ever repeated purchase and sale of labour-power is now the mere form; what really takes place is this - the capitalist again and again appropriates, without equivalent, a portion of the previously materialised labour of others, and exchanges it for a greater quantity of living labour. At first the rights of property seemed to us to be based on a man's own labour. At least, some such assumption was necessary since only commodity-owners with equal rights confronted each other, and the sole means by which a man could become possessed of the commodities of others, was by alienating his own commodities; and these could be replaced by labour alone. Now, however, property turns out to be the right, on the part of the capitalist, to appropriate the unpaid labour of others or its product, and to be the impossibility, on the part of the labourer, of appropriating his own product. The separation of property from labour has become the necessary consequence of a law that apparently originated in their identity. [6]
To be sure, the matter looks quite different if we consider capitalist production in the uninterrupted flow of its renewal, and if, in place of the individual capitalist and the individual worker, we view in their totality, the capitalist class and the working-class confronting each other. But in so doing we should be applying standards entirely foreign to commodity production.