Capital as self-expanding value embraces not only class relations,
 a society of a definite character resting on the existence of labour in
 the form of wage-labour. It is a movement, a circuit-describing process
 going through various stages, which itself comprises three different forms
 of circuit-describing process. Therefore it can be understood only as a
 motion, not as a thing at rest. Those who regard the gaining by value of
 independent existence as a mere abstraction forget that the movement of
 industrial capital is this abstraction in actu. Value here passes
 through various forms, various movements in which it maintains itself and
 at the same time expands, augments. As we are here concerned primarily
 with the mere form of this movement, we shall not take into consideration
 the revolutions which capital-value may undergo during its circuit. But
 it is clear that in spite of all the revolutions of value, capitalist production
 exists and can endure only so long as capital-value is made to create surplus-value,
 that is, so long as it describes its circuit as a value that has gained
 independence, so long therefore as the revolutions in value are overcome
 and equilibrated in some way. The movements of capital appear as the action
 of some individual industrial capitalist who performs the functions of
 a buyer of commodities and labour, a seller of commodities, and an owner
 of productive capital, who therefore promotes the circuit by this activity.
 If social capital experiences a revolution in value, it may happen that
 the capital of the individual capitalist succumbs to it and fails, because
 it cannot adapt itself to the conditions of this movement of values. The
 more acute and frequent such revolutions in value become, the more does
 the automatic movement of the now independent value operate with the elemental
 force of a natural process, against the foresight and calculation of the
 individual capitalist, the more does the course of normal production become
 subservient to abnormal speculation, and the greater is the danger that
 threatens the existence of the individual capitals. These periodical revolutions
 in value therefore corroborate what they are supposed to refute, namely,
 that value as capital acquires independent existence, which it maintains
 and accentuates through its movement.