Reserve army of labour

In Das Kapital, Volume I, Chapter 25, Section 3, titled "Progressive Production of a Relative surplus population or Industrial Reserve Army", Karl Marx develops the idea of an reserve army of labour, also sometimes called an industrial reserve army, or reserve army of unemployed, or relative surplus population. Marx did not invent the term "reserve army of labour". It was already being used by Friedrich Engels in his 1845 book The Condition of the Working Class in England. What Marx did was theorize the reserve army of labour as a necessary part of the capitalist organization of labour-power.

History and development of the idea of the reserve army of labour

Pre-Marxist use, before 1845

According to Michael Denning, writing for the New Left Review, Issue #66, in December 2010, in an article titled "Wageless Life", the concept of a reserve army of labour was used before Engels by the Chartist labor leader Bronterre O’Brien as early as 1839:

Radicals, particularly the Chartists and Fourierist associationists, imagined the new factory workers as great industrial armies, and this common trope led the Chartist leader Bronterre O'Brien to write of a reserve army of labour in the Northern Star in 1839. The young Engels picked up that image in The Condition of the Working Class in England in 1844, and Marx would invoke the metaphor occasionally, distinguishing between the active and reserve armies of the working class. By the end of the nineteenth century, it was part of the commonsense understanding of unemployment: by 1911, even the Massachusetts Bureau of Statistics of Labor could conclude that, ‘however prosperous conditions may be, there is always a “reserve army” of the unemployed’

First socialist use of the idea by Engels, 1845

In The Condition of the Working Class in England, in the chapter titled "Competition," Engels introduces the idea of the "reserve army of workers" in the following passage:

[...]English manufacture must have, at all times save the brief periods of highest prosperity, an unemployed reserve army of workers, in order to be able to produce the masses of goods required by the market in the liveliest months. This reserve army is larger or smaller, according as the state of the market occasions the employment of a larger or smaller proportion of its members. And if at the moment of highest activity of the market the agricultural districts and the branches least affected by the general prosperity temporarily supply to manufacture a number of workers, these are a mere minority, and these too belong to the reserve army, with the single difference that the prosperity of the moment was required to reveal their connection with it. When they enter upon the more active branches of work, their former employers draw in somewhat, in order to feel the loss less, work longer hours, employ women and younger workers, and when the wanderers discharged at the beginning of the crisis return, they find their places filled and themselves superfluous – at least in the majority of cases. This reserve army, which embraces an immense multitude during the crisis and a large number during the period which may be regarded as the average between the highest prosperity and the crisis, is the “surplus population” of England, which keeps body and soul together by begging, stealing, street-sweeping, collecting manure, pushing hand-carts, driving donkeys, peddling, or performing occasional small jobs. In every great town a multitude of such people may be found. It is astonishing in what devices this “surplus population” takes refuge. —  Friedrich Engels, The Condition of the Working Class in England, 1845

In the above passage, Engels gives the broad strokes of the idea, establishing:

• The reserve army of unemployed workers is sought after precisely because of their unemployment. This unemployment makes them available for the "liveliest" months of market activity, during which "greater masses of goods are required," (i.e. are more demanded by consumers) compared with the rest of the year. A modern example of this principle in action might be the type of a chronically unemployed person who gets a low-paying part-time job at a Halloween store, selling costumes during the month of October.
• These "liveliest months" of market activity constitute a form of economic crisis in miniature. Engels refers to the reserve army as "the wanderers discharged at the beginning of the crisis."
• The reserve army of workers includes not only the chronically unemployed, but the chronically under-employed, who belong to the "districts and the branches least affected by the general prosperity[...]", i.e. the internal colonies, those parts of a given geographical region which have a lower standard of living than their surroundings.
• when the chronically under-employed [men] return to their original jobs after being used as part of the reserve army of workers, they find their positions have been taken workers who, owing to their social position, are even more desperate and marginalized than themselves, usually women and children, in the historical context in which Engels was writing. This marginalizes the men further, and makes them part of a "surplus population."
• This "surplus population" often becomes part of the lumpenproletariat, or homeless, and must keep itself alive through crime, begging, and unpleasant odd jobs. This makes them more subject to death, disease, imprisonment, and exploitation above and beyond what is usual even for the average proletariat.
• This "surplus population" can be found "in every great town" of England, and by extension, every geographical region in which the capitalist mode of production prevails.

Development of the idea by Marx

The first mention of the reserve army of labour in Marx's writing occurs in a manuscript entitled "Wages", which he wrote in 1847, but did not publish:

Big industry constantly requires a reserve army of unemployed workers for times of overproduction. The main purpose of the bourgeois in relation to the worker is, of course, to have the commodity labour as cheaply as possible, which is only possible when the supply of this commodity is as large as possible in relation to the demand for it, i.e., when the overpopulation is the greatest. Overpopulation is therefore in the interest of the bourgeoisie, and it gives the workers good advice which it knows to be impossible to carry out. Since capital only increases when it employs workers, the increase of capital involves an increase of the proletariat, and, as we have seen, according to the nature of the relation of capital and labour, the increase of the proletariat must proceed relatively even faster. The above theory, however, which is also expressed as a law of nature, that population grows faster than the means of subsistence, is the more welcome to the bourgeois as it silences his conscience, makes hard-heartedness into a moral duty and the consequences of society into the consequences of nature, and finally gives him the opportunity to watch the destruction of the proletariat by starvation as calmly as any other natural event without bestirring himself, and, on the other hand, to regard the misery of the proletariat as its own fault and to punish it. To be sure, the proletarian can restrain his natural instinct by reason, and so, by moral supervision, halt the law of nature in its injurious course of development. — Karl Marx, Wages, 1847