Just as it passed from the hands of B,the buyer,into those of A,the seller,so now it passes from the hands of A,who has become a buyer,into those of C.The changes in the form of a commodity,its transformation into money and its retransformation from money,in other words the movement of the total metamorphosis of a commodity,accordingly appear as the extrinsic movement of a single coin which changes places twice,with two different commodities.However scattered and fortuitous the simultaneous purchases and sales may be,a buyer is always confronted by a seller in actual circulation,and the money which takes the place of the commodity sold must already have changed places once with another commodity before reaching the hands of the buyer.On the other hand,sooner or later the money will pass again from the hands of the seller who has become a buyer into those of a new seller,and its repeated changes of place express the interlocking of the metamorphoses of commodities.The same coins therefore proceed --always in the opposite direction to the commodities moved --from one point of the circuit to another;some coins move more frequently,others less frequently,thus describing a longer or shorter curve.The different movements of one and the same coin can follow one another only temporally,just as conversely the multiplicity and fragmentation of the purchases and sales are reflected in the simultaneous and spatially concurrent changes of place of commodity and money.
The simple form of commodity circulation,C --M --C,takes place when money passes from the hands of the buyer into those of the seller and from the seller who has become a buyer into the hands of a new seller.This concludes the metamorphosis of the commodity and hence the movement of money in so far as it is the expression of this metamorphosis.But since there are new use-values produced continuously in the form of commodities,which must therefore be thrown continuously afresh into the sphere of circulation,the circuit C --M --C is renewed and repeated by the same commodity-owners.The money they have spent as buyers returns to them when they once more become sellers of commodities.The perpetual renewal of commodity circulation is reflected in the fact that over the entire surface of bourgeois society money not only circulates from one person to another but that at the same time it describes a number of distinct small circuits,starting from an infinite variety of points and returning to the same points,in order to repeat the movement afresh.
As the change of form of the commodity appears as a mere change in place of money,and the continuity of the movement of circulation belongs entirely to the monetary side --because the commodity always makes only one step in the direction opposite to that of money,money however invariably making the second step for the commodity to complete the motion begun by the commodity --so the entire movement appears to be initiated by money,although during the sale the commodity causes the money to move,thus bringing about the circulation of the money in the same way as during the purchase the money brings about the circulation of the commodity.Since moreover money always confronts commodities as a means of purchase and as such causes commodities to move merely by realising their prices,the entire movement of circulation appears to consist of money changing places with commodities by realising their prices either in separate transactions which occur simultaneously,side by side,or successively when the same coin realises the prices of different commodities one after another.If,for example,one examines C --M --C'--M --C"--M --C"',etc.,and disregards the qualitative aspects,which become unrecognisable in actual circulation,there emerges only the same monotonous operation.After realising the price of C,M successively realises the prices of C',C",etc.,and the commodities C',C",C''',etc.,invariably take the place vacated by money.It thus appears that money causes the circulation of commodities by realising their prices.While it serves to realise prices,money itself circulates continuously,sometimes moving merely to a different place,at other times tracing a curve or describing a small cycle in which the points of departure and of return are identical.As a medium of circulation it has a circulation of its own.The movement and changing forms of the circulating commodities thus appear as the movement of money mediating the exchange of commodities,which are in themselves immobile.The movement of the circulation process of commodities is therefore represented by the movement of money as the medium of circulation,i.e.,by the circulation of money .
