The law of capitalist production, that is at the bottom of the pretended
 “natural law of population,” reduces itself simply to this: The
 correlation between accumulation of capital and rate of wages is nothing else
 than the correlation between the unpaid labour transformed into capital, and
 the additional paid labour necessary for the setting in motion of this
 additional capital. It is therefore in no way a relation between two
 magnitudes, independent one of the other: on the one hand, the magnitude of the
 capital; on the other, the number of the labouring population; it is rather, at
 bottom, only the relation between the unpaid and the paid labour of the same
 labouring population. If the quantity of unpaid labour supplied by the working
 class, and accumulated by the capitalist class, increases so rapidly that its
 conversion into capital requires an extraordinary addition of paid labour, then
 wages rise, 582and, all other circumstances remaining equal, the unpaid
 labour diminishes in proportion. But as soon as this diminution touches the
 point at which the surplus labour that nourishes capital is no longer supplied
 in normal quantity, a reaction sets in: a smaller part of revenue is
 capitalised, accumulation lags, and the movement of rise in wages receives a
 check. The rise of wages therefore is confined within limits that not only
 leave intact the foundations of the capitalistic system, but also secure its
 reproduction on a progressive scale. The law of capitalistic accumulation,
 metamorphosed by economists into pretended law of Nature, in
 reality merely states that the very nature of accumulation excludes every
 diminution in the degree of exploitation of labour, and every rise in the price
 of labour, which could seriously imperil the continual reproduction, on an
 ever-enlarging scale, of the capitalistic relation. It cannot be otherwise in a
 mode of production in which the labourer exists to satisfy the needs of
 self-expansion of existing values, instead of, on the contrary, material wealth
 existing to satisfy the needs of development on the part of the labourer. As,
 in religion, man is governed by the products of his own brain, so in
 capitalistic production, he is governed by the products of his own hand. [10]