After the commodity has received in the process of price determination the form in which it becomes capable of circulation, and after gold has acquired the character of money in the same process, circulation will both present and solve the contradictions which are inherent in the process of exchange of commodities. The actual exchange of commodities, i. e., the social interchange of matter consists of a change of form in which is unfolded the double character of the commodity as use-value and exchange value, and at the same time its own change of form is crystallized in distinct forms of money. To describe this change of form is to describe circulation. As we have seen, given a world of commodities and with it a system of division of labor, commodity is but a developed form of exchange value; in the same manner, circulation implies a steady stream of exchange transactions which are being continually renewed on all sides. The second assumption we make is that commodities enter the process of exchange with a _definite price_ or that they appear to each other in that process in a double capacity, really as use-values, ideally―in price―as exchange values. The liveliest streets of London are crowded with stores whose show windows are filled with the riches of the world, Indian shawls, American revolvers, Chinese porcelain, Parisian corsets, Russian furs and tropical spices, but all of these things of joy bear fatal white labels marked with Arabian figures with the laconic characters £, s., d. Such is the picture of the commodity appearing in circulation. a. THE METAMORPHOSIS OF COMMODITIES. On close examination the process of circulation is seen to consist of two distinct cycles. If we denote commodity by the letter C and money by the letter M we can express these two forms as follows: C―M―C M―C―M. In this chapter we are interested exclusively in the first form, i. e., in the form which serves as the direct expression of the circulation of commodities. The process C―M―C consists of the movement C―M, the exchange of the commodity for money, or _selling_; the opposite movement M―C, exchange of money for a commodity, or _buying_; and of the unity of the two movements C―M―C, exchange of the commodity for money in order to exchange the money for a commodity, or _selling_ in order to _buy_. But the result which marks the end of the process is C―C, exchange of commodity for commodity, real interchange of matter.