The law of supply and demand for labour power is perverse in that the more fertile labour power's use value as a source of surplus value becomes, the lower its value and, consequently, its exchange value. Clearly such a perverse law is difficult to explain. It is paradoxical and counter-intuitive.
Perhaps Marx was wary of repeating himself or of giving explanations that confuse the reader because they are so damned convoluted. Whatever the reason, he held back from closing the deal. His discussion of relative surplus population does not drill down to the bedrock of his value theory -- abstract average socially necessary labour time. Instead, he railed against Political Economy for its apologetic and opportunistic dogma of supply and demand:
The action of the law of supply and demand of labour on this basis completes the despotism of capital. As soon, therefore, as the labourers learn the secret, how it comes to pass that in the same measure as they work more, as they produce more wealth for others, and as the productive power of their labour increases, so in the same measure even their function as a means of the self-expansion of capital becomes more and more precarious for them; as soon as they discover that the degree of intensity of the competition among themselves depends wholly on the pressure of the relative surplus population; as soon as, by Trades’ Unions, &c., they try to organise a regular co-operation between employed and unemployed in order to destroy or to weaken the ruinous effects of this natural law of capitalistic production on their class, so soon capital and its sycophant, Political Economy, cry out at the infringement of the “eternal” and so to say “sacred” law of supply and demand. Every combination of employed and unemployed disturbs the “harmonious” action of this law. But, on the other hand, as soon as (in the colonies, e.g.) adverse circumstances prevent the creation of an industrial reserve army and, with it, the absolute dependence of the working class upon the capitalist class, capital, along with its commonplace Sancho Panza, rebels against the “sacred” law of supply and demand, and tries to check its inconvenient action by forcible means and State interference. p 599-600.
In the flurry of indignant rhetoric, Marx appears to have misplaced his value theory and conjured up a new theory, the "absolute general law of capitalist accumulation" to explain what his value theory could have more adequately explained:
The same causes which develop the expansive power of capital, develop also the labour power at its disposal. The relative mass of the industrial reserve army increases therefore with the potential energy of wealth. But the greater this reserve army in proportion to the active labour army, the greater is the mass of a consolidated surplus population, whose misery is in inverse ratio to its torment of labour. The more extensive, finally, the lazarus layers of the working class, and the industrial reserve army, the greater is official pauperism. This is the absolute general law of capitalist accumulation. p.601
What Marx called here "the absolute general law of capitalist accumulation" is instead a consequence of the law of value as it manifests itself in the specifically-capitalist mode of production. There are not two laws. Marx's "absolute general law of capitalist accumulation" is a corollary of the law of value.
Accumulation is what happens when the law of value is fully operational in a capitalist society. Marx appears to have forgotten in these chapters that his exposition of simple commodity production and exchange was an abstraction from capitalist social relations and mode of production. As Engels pointed out some years later, "The value form of products therefore already contains in embryo the whole capitalist form of production, the antagonism between capitalists and wage-workers, the industrial reserve army, crises." Thus surplus value already contains in embryo accumulation:
But all methods for the production of surplus-value are at the same time methods of accumulation; and every extension of accumulation becomes again a means for the development of those methods. p 604
"All methods for the production of surplus-value" boil down to the buying and selling of labour power. In other words, chapter six, the first place where Marx could have been more explicit about the role of socially necessary labour time in establishing the value of labour power, but wasn't.
Beneath Capital are several layers of draft manuscripts that trace the erasure of the bombastic epiphanies of Necessary Labour. Surplus Labour. Surplus Population. Surplus Capital. Most relevant to the discussion of accumulation, machinery and the relative surplus population is a second draft of the chapter on machinery in the 1861-63 manuscripts.
The draft chapter on machinery in the manuscript begins:
John Stuart Mill remarks: "It is questionable, if all the mechanical inventions yet made have lightened the day's toil of any human being." He should have said, OF ANY TOILING HUMAN BEING. But on the basis of capitalist production the purpose of machinery is by no means TO LIGHTEN OR SHORTEN THE DAYS TOIL of the worker.
Chapter 15 of volume one of Capital begins:
John Stuart Mill says in his Principles of Political Economy: "It is questionable if all the mechanical inventions yet made have lightened the day’s toil of any human being." That is, however, by no means the aim of the capitalistic application of machinery.
The draft chapter runs from pages 318 to 346 of volume 30 of the Marx-Engels Collected Works. It continues through pages 372 to 387 of volume 33 and concludes in pages 8 to 60 of volume 34. The phrase, socially necessary labour time (or labour time socially necessary), appears six times on those pages. I don't know how to explain this conspicuous discrepancy between the draft and the published version.
Of particular interest is a three paragraph passage from the sections in volume 34. As a footnote explains: "The passage comprising here the three foregoing paragraphs was taken over by Marx, with some alterations, from the Manuscripts of 1857-58 (see present edition, Vol. 28, pp. 326-27)."
The passage on pp. 326-27 of volume 28 (Grundrisse) happens to be one of the three passages in the Grundrisse that play intensively on the tension between the necessary and the superfluous, in which under capitalism the necessary becomes superfluous and the superfluous becomes necessary. That is to say the inversion in capitalism of the superfluous (überflüssig) and the necessary (notwendig) -- labour time and surplus population (i.e., labour capacity) -- that I have promised to discuss in a future post. That will still require its own post -- this one is already too long -- but I will mention here that the other two passages are "Necessary labour. Surplus labour. Surplus population. Surplus capital" and a large part of the infamous "Fragment on Machines." Two of the passage cite The Source and Remedy of the National Difficulties affirmatively.
Obviously that future post on the superfluous and the necessary should be my next post. I will leave the reader, though, with one more tidbit from Marx's draft chapter on machinery. In a parenthesis in the first paragraph -- clearly for his own reference -- is the phrase, "surplus population and surplus capital." In the Grundrisse passage Marx reworked in that second draft one finds the parenthetical remark, "Hence the correctness of the theory of surplus population and surplus capital (emphasis added)."
Where is this theory of surplus population and surplus capital? One likely place is the passage in the Grundrisse titled "Necessary labour. Surplus labour. Surplus population. Surplus capital," which follows directly after critical commentary on Malthus. Malthus also commented on surplus population and surplus capital:
But it appears to me perfectly clear in theory, and universally confirmed by experience, that the employment of capital may, and in fact often does, find a limit, long before there is any real difficulty in procuring the means of subsistence; and that both capital and population may be at the same time, and for a period of considerable length, redundant, compared with the effectual demand for produce.
Engels, in his "Outlines of a Critique of Political Economy" (1844) briefly mentioned the connection between surplus population and surplus capital:
If Malthus had not considered the matter so one-sidedly, he could not have failed to see that surplus population or labour-power is invariably tied up with surplus wealth, surplus capital and surplus landed property.
But neither of these remarks constitutes a theory. This is a theory.