b. THE CIRCULATION OF MONEY.
Actual circulation appears at first sight as a mass of purchases and sales accidentally taking place side by side. In buying as in selling, commodities and money always stand in the same mutual relation: the seller, on the side of the commodity; the buyer, on that of money. Money as a medium of circulation always appears therefore as a means of purchase; and in that way the difference in its destinations in the opposite phases of the metamorphosis of the commodity becomes indistinguishable.
Money passes into the hands of the seller in the same transaction in which the commodity passes into the hands of the buyer. Commodities and money thus flow in opposite directions and this change of place in which the commodity passes over to one side and money to the other side, occurs simultaneously at an indefinitely large number of points on the entire surface of bourgeois society. But the first step which the commodity makes in the sphere of circulation is also its last step.72 Whether it leaves its place on account of its attraction for gold (C—M), or on account of its attraction by gold (M—C), with one move, with one change of place it falls out of the sphere of circulation into that of consumption. Circulation is a continuous flow of commodities, but different commodities all the time, since each commodity makes but one move. Every commodity enters upon the second phase of its circulation not as the same commodity, but as another commodity, gold. Hence the movement of a metamorphosed commodity is the movement of gold. The same piece of gold or the identical gold coin which changed places with one commodity in the act C—M, reappears from the opposite end