The exchange value of a commodity is not revealed in its own use-value. But, as the embodiment universal social labor-time, the use-value of one commodity bears a certain ratio to the use-values of other commodities. Thus, the exchange value of one commodity is manifested in the use-values of other commodities. An equivalent is, in fact, the exchange value of one commodity expressed in the use-value of another commodity. If I say, e. g., that one yard of linen is worth two pounds of coffee, then the exchange value of linen is expressed in terms of the use-value of coffee, viz., in a certain quantity of that use-value. This ratio being given, I can express the value of any quantity of linen in coffee. It is clear that the exchange value of one commodity, say linen, is not confined to the ratio of any one commodity, e. g. coffee, as its equivalent. The quantity of universal labor-time which is represented in one yard of linen is at the same time embodied in an endless variety of volumes of use-values of all other commodities. The use-value of any other commodity forms the equivalent of one yard of linen, in the proportion in which it represents the same quantity of labor-time as that yard of linen. The exchange value of _this single commodity_ is, therefore, fully expressed in the endless number of equations in which the use-values of all other commodities form its equivalents. Not until the exchange value of a commodity is expressed in the sum total of these equations or of the different proportions in which one commodity is exchanged for every other commodity, does it find an exhaustive expression as a _universal equivalent_; e. g., the series of equations: 1 yard of linen = 1/2 lb. of tea, 1 yard of linen = 2 lbs. of coffee, 1 yard of linen = 8 lbs. of bread, 1 yard of linen = 6 yards of calico, may be represented as follows: 1 yard of linen = 1/8 lb. of tea + 1/2 lb. of coffee + 2 lbs. of bread + 1-1/2 yards of calico. Therefore, if we had before us the sum total of the equations, in which the value of a yard of linen is exhaustively expressed, we could represent its exchange value in the form of a series. As a matter of fact, the series is an endless one, since the circle of commodities, constantly expanding, can never be closed up. But while the exchange value of one commodity is thus measured by the use-values of all other commodities, the exchange values of all the other commodities are, in their turn, measured by the use-value of this one commodity.[11]