But just because the circuit C' ... C' presupposes within its
 sphere the existence of other industrial capital in the form of C (equal
 to L + MP) — and MP comprises diverse other capitals, in our case for
 instance machinery, coal, oil, etc. — it clamours to be considered not
 only as the general form of the circuit, i.e., not only as a social form
 in which every single industrial capital (except when first invested) can
 be studied, hence not merely as a form of movement common to all individual
 industrial capitals, but simultaneously also as a form of movement of the
 sum of the individual capitals, consequently of the aggregate capital of
 the capitalist class, a movement in which that of each individual industrial
 capital appears as only a partial movement which intermingles with the
 other movements and is necessitated by them. For instance if we regard
 the aggregate of commodities annually produced in a certain country and
 analyse the movement by which a part of it replaces the productive capital
 in all individual businesses, while another part enters into the individual
 consumption of the various classes, then we consider C' ... C' as a form
 of movement of social capital as well as of the surplus-value, or surplus-product,
 generated by it. The fact that the social capital is equal to the sum of
 the individual capitals (including the joint-stock capital or the state
 capital, so far as governments employ productive wage-labour in mines,
 railways, etc., perform the function of industrial capitalists), and that
 the aggregate movement of social capital is equal to the algebraic sum
 of the movements of the individual capitals, does not in any way preclude
 the possibility that this movement as the movement of a single individual
 capital, may present other phenomena than the same movement does when considered
 from the point of view of a part of the aggregate movement of social capital,
 hence in its interconnections with the movements of its other parts, and
 that the movement simultaneously solves problems the solution of which
 must be assumed when studying the circuit of a separate, individual capital
 instead of being the result of such study.