I understand that most of Marx’s formulations are necessarily generic and that apparent exceptions, contradictions or otherwise complications are part of the problem he is trying to address in Capital. Think of Robert’s example of the tipped employee and the complexity of labour-power he highlights. (I never liked the service industry for the very reasons that wages were never clear to me).
Even as I avoid the service industry, I cannot escape other critical questions concerning the value of labour-power. Jonathan, for instance, is sharp to ask whether “services have different value because of the training” it takes to achieve its labor, and if in such case we are also paying “for all of the value of accumulated medical school?” Your inference that “we consume [labor] like other commodities” seems spot on, Jonathan. I refer to chapter 6 where Marx treats labor as a commodity. According to Marx, what determines the value of “labour-power” is, “as in the case of every other commodity… the labour-time necessary for the production, and consequently also the reproduction, of this specific article” (274). How is it, we might ask, that the cost of an hour consultation at the doctor’s office (or a law firm) is not so indicative of its “labour-time” necessary for its production? What we must also take into account is that the value of labour-power is also dependent of “reproduction,” not of the labor itself (the hour consultation) but of doctor or lawyer himself.
In Marx’s formulation, “the production of labour-power consists in his reproduction of himself or his maintenance” (274). The value of labour-power is based on “the value of the means of subsistence necessary for the maintenance of its owner”—one that will vary with each individual. (I assume that when we speak of high paying careers such as lawyers and doctors, we are thinking of the more prestigious positions held. “Not all lawyers make a lot of money” seems the obvious observation here, but the distribution of wages or purchase of these as labor/commodities has other variants). Still, our purchase of that labor/commodity does seem to take into account the time of training and its tuition cost, as well other expenses that fit the category of owner-maintenance prescribed here (274).