I. M—C...P...C'—M'
II. P...Tc...P
III. Tc...P (C')
If we take all three diagrams together, all premises of the process appear as its effects, as premises produced by itself. Every element appears as a point of departure, transit, and return to the starting point. The total process appears as the unity of the processes of production and circulation. The process of production mediates the process of circulation, and vice versa.
All three cycles have the following point in common: The creation of more value as the compelling motive. Diagram I expresses this by its form. Diagram II begins with P, the process of creating surplus-values. Diagram III begins the cycle with the utilized value and closes with renewed utilized value, even if the movement is repeated on the same scale.
So far as C—M means M—C from the point of view of the buyer, and M—C means C—M from the point of view of the seller, the circulation of capital presents only the features of the ordinary metamorphosis of commodities, subject to the laws relative to the amount of money in circulation, as analyzed in volume I, chap. III, 2. But if we do not cling to this formal aspect, but rather consider the actual connection of the metamorphoses of the various individual capitals, in other words, if we study the interrelation of the cycles of individual capitals as partial movements of the process of reproduction of the total social capital, them the mere change of form between money and commodities does not explain matters.
In a continuously revolving circle, every point is simultaneously a point of departure and point of return. If we interrupt the rotation, not every point of departure is a point of return. We have seen, for instance, that not only does every individual cycle imply the existence of the others, but also that the repetition of one cycle in a certain form necessitates the rotation of this cycle through its other forms. The entire difference thus assumes a formal aspect, it appears as a mere subjective difference made for the convenience of the observer.
In so far as every one of these cycles is studied as a special form of movement through which various individual industrial capitals are passing, their differences have but an individual nature. But in reality every individual industrial capital is contained simultaneously in all three cycles. These three cycles, the forms of reproduction assumed by the three modes of capital, rotate continuously side by side. For instance, one part of capital value which now performs the function of commodity-capital, is transformed into money-capital, but at the same time another part leaves the process of production and enters the circulation as a new commodity-capital. The cycle C'...C' is thus continuously rotating, and so are the two other forms. The reproduction of capital in each one of its forms and stages is just as continuous as the metamorphoses of these forms and their successive transition through the three stages. The entire circulation is thus actually a unit with these three forms.
We assumed in our analysis that the entire volume of capital-value acts either as money-capital, productive capital, or commodity-capital. For instance, we had those 422 pounds sterling first in the role of money-capital, then we transformed them entirely into productive capital, and finally into commodity-capital, into yarn valued at 500 pounds sterling and containing 78 pounds sterling of surplus-value. Here the various stages are so many interruptions. So long as, for instance, those 422 pounds sterling retain the form of money, that is to say until the purchases M—C (L plus Pm) have been made, the entire capital exists only in the form of money-capital and performs its functions. But as soon as it is transformed into productive capital, it performs neither the functions of money-capital nor of commodity-capital. Its entire process of circulation is interrupted, just as on the other hand its entire process of production is interrupted, as soon as it performs any functions in one of its two circulation stages, either as M or as C. From this point of view, the cycle P...P would not only present a periodical renewal of the productive capital, but also the interruption of its function, the process of production, up to the time when the process of circulation is completed. Instead of proceeding continuously, production took place in jumps and was renewed only in periods of uncertain duration, according to whether the two stages of the process of circulation were completed fast or slowly. This would apply, for instance, to a Chinese artisan, who works only for private customers and whose process of production is interrupted, until he receives a new order.
This is true of every individual part of capital in process of circulation, and all parts of capital pass through this circulation in succession. For instance, the 10,000 lbs, of yarn are the weekly product of some spinner. These 10,000 lbs. of yarn leave the sphere of production in their entirety and enter the sphere of circulation. The capital-value contained in them must all be converted into money-capital, and so long as it retains the form of money-capital, it cannot return into the process of production. It must first go into circulation and be reconverted into the elements of productive capital, L plus Pm. The process of rotation of capital is a succession of interruptions, leaving one stage and entering the next, discarding one form and assuming another. Every one of these stages not only cause the next, but also excludes it.
But continuity is the characteristic mark of capitalist production, conditioned on its technical basis, although not absolutely attainable. Let us see, then, what passes in reality. While the 10,000 lbs. of yarn appear on the market as commodity-capital and are transformed into money (regardless of whether it is a paying, purchasing, or calculating medium), new cotton, coal, etc., take the place of the yarn in the process of production, having been reconverted from the form of money and commodities into that of productive capital and performing its functions. At the time when these 10,000 lbs. of yarn are converted into money, the preceding 10,000 lbs. are going through the second stage of circulation and are reconverted from money into the elements of productive capital. All parts of capital pass successively through the process of rotation and are simultaneously in its different stages. The industrial capital thus exists simultaneously in all the successive stages of its rotation and in the various forms corresponding to its functions. That part of industrial capital, which is for the first time converted from commodity-capital into money, begins the cycle C'...C', while industrial capital as a rotating body of aggregates, has passed through it. One hand advances money, the other receives it. The inauguration of the cycle M...M' at one place coincides with its return to the starting point of another. The same is true of productive capital.
The actual rotation of industrial capital in its continuity is therefore not alone the unity of the processes of production and circulation, but also the unity of its three cycles. But it can be such a unity only, if every individual part of capital can go successively through the various stages of the rotation, pass from one phase and from one functional form to another, so that the industrial capital, being the aggregate of all these parts, is found simultaneously in its various phases and functions and describes all three cycle at the same time. The succession of these parts is conditioned on their simultaneous existence side by side, that is to say, on the division of capital. In a systematized manufacture, the product is as much ubiquitous in the various stages of its process of formation, as it is in the transition from one phase of production to another. As the individual industrial capital has a definite volume which does not merely depend on the means of the capitalist and which has a minimum magnitude for every branch of production, it follows that its division must proceed according to definite proportions. The magnitude of the available capital determines the volume of the process of production, and this, again, determines the size of the commodity-capital and money-capital which perform their functions simultaneously with the process of production. The simultaneous functions, which enable the production to proceed continuously, are only due to the rotation of the various parts of capital which pass successively through their different stages. The simultaneousness is merely the result of the succession. For if the rotation of one phase, for instance of C'—M', is interrupted for one of the parts of capital, if the commodity cannot be sold, then the cycle of this part is broken and the reproduction of its elements of production cannot take place; the succeeding parts, which come out of the process of production in the shape of C', find the conversion of their function blocked by their predecessors. If this is continued for some time, production is restricted and the entire process arrested. Every stop of the succession carries disorder into the simultaneousness of the cycles, every obstruction of one stage causes more or less obstruction in the entire rotation, not only of the obstructed part of capital,