CHAPTER II.

and the same labor-time is realized in unequal volumes of use-values with the change in the productive power of concrete labor. In estimating all commodities in gold it is only assumed that gold represents a given quantity of labor at a given moment, as was done when the exchange value of any commodity was expressed in terms of the use-value of any other commodity. As for the variations of the value of gold, the law of exchange value formulated above holds good in its case as well. If the exchange value of commodities remains unchanged, then a general rise in their gold prices is possible only in the case of a fall in the exchange value of gold. If the exchange value of gold remains unchanged, a general rise of gold prices is possible only when the exchange value of all commodities rises. The reverse is true in case of a general fall in the prices of commodities. If the value of an ounce of gold falls or rises in consequence of a change in the labor-time required for its production, then the values of all other commodities fall or rise to an equal extent. Thus, the ounce of gold represents after the change, as it did before, a given quantity of labor-time with regard to all commodities. The same exchange values are now estimated in greater or smaller quantities of gold than before, but they are estimated in proportion to the magnitude of their values, and consequently retain the same proportion to each other. The ratio 2 ÷ 4 ÷ 8 remains the same when expressed as 1 ÷ 2 ÷ 4 or as 4 ÷ 8 ÷ 16. The change in the quantity of gold in which exchange values are estimated with a variation in the value of gold, interferes as little with the function of gold as a measure of value, as the fifteen times smaller value of silver as compared with that of gold interferes with the performance of that function by the latter. Since labor-time is the common measure of gold and commodities, and since gold figures as the measure of value only in so far as all commodities are measured by it, the idea that money makes commodities commensurable, is therefore a mere fiction