Page:Principles of Political Economy Vol 1.djvu/560

538 is the extreme limit of value in exchange. The exchange value of a thing may fall short, to any amount, of its value in use; but that it can ever exceed the value in use, implies a contradiction; it supposes that persons will give, to possess a thing, more than the utmost value which they themselves put upon it as a means of gratifying their inclinations.

The word Value, when used without adjunct, always means, in political economy, value in exchange; or as it has been called by Adam Smith and his successors, exchangeable value, a phrase which no amount of authority that can be quoted for it can make other than bad English. Mr. De Quincey substitutes the term Exchange Value, which is unexceptionable.

Exchange value requires to be distinguished from Price. The words Value and Price were used as synonymous by the early political economists, and are not always discriminated even by Ricardo. But the most accurate modern writers, to avoid the wasteful expenditure of two good scientific terms on a single idea, have employed Price to express the value of a thing in relation to money; the quantity of money for which it will exchange. By the price of a thing, therefore, we shall henceforth understand its value in money; by the value, or exchange value of a thing, its general power of purchasing; the command which its possession gives over purchaseable commodities in general.

§ 3.But here a fresh demand for explanation presents itself. What is meant by command over commodities in general? The same thing exchanges for a great quantity of some commodities, and for a very small quantity of others. A suit of clothes exchanges for a great quantity of bread, and for a very small quantity of precious stones. The value of a thing in exchange for some commodities may be rising, for others falling. A coat may exchange for less bread this year than last, if the harvest has been bad, but for more glass or iron, if a tax has been taken off those commodities, or an