THE MEASURE OF VALUE.
It is generally allowed that the word value, in common language, has two different meanings; one, value in use, the other, value in exchange; the first expressing merely the usefulness of an object in supplying the most important wants of mankind, without reference to its power of commanding other objects in exchange; and the second expressing the power of commanding other objects in exchange, without reference to its usefulness in supplying the most important wants of mankind.
It is obviously value in the last sense, not the first, with which the science of Political Economy is mainly concerned.
But the power of one object to command another in exchange, or in other words the power of purchasing, may obviously arise either from causes affecting the object itself, or the commodities against which it is exchanged.
