Front Page Titles (by Subject) Want of a Measure of Value. - Money and the Mechanism of Exchange
The Online Library of Liberty
A project of Liberty Fund, Inc.
Want of a Measure of Value. - William Stanley Jevons, Money and the Mechanism of Exchange 
Money and the Mechanism of Exchange (New York: D. Appleton and Co. 1876).
About Liberty Fund:
Liberty Fund, Inc. is a private, educational foundation established to encourage the study of the ideal of a society of free and responsible individuals.
The text is in the public domain.
Fair use statement:
This material is put online to further the educational goals of Liberty Fund, Inc. Unless otherwise stated in the Copyright Information section above, this material may be used freely for educational and academic purposes. It may not be used in any way for profit.
Want of a Measure of Value.
A second difficulty arises in barter. At what rate is any exchange to be made? If a certain quantity of beef be given for a certain quantity of corn, and in like manner corn be exchanged for cheese, and cheese for eggs, and eggs for flax, and so on, still the question will arise—How much beef for how much flax, or how much of any one commodity for a given quantity of another? In a state of barter the price-current list would be a most complicated document, for each commodity would have to be quoted in terms of every other commodity, or else complicated rule-of-three sums would become necessary. Between one hundred articles there must exist no less than 4950 possible ratios of exchange, and all these ratios must be carefully adjusted so as to be consistent with each other, else the acute trader will be able to profit by buying from some and selling to others.
All such trouble is avoided if any one commodity be chosen, and its ratio of exchange with each other commodity be quoted. Knowing how much corn is to be bought for a pound of silver, and also how much flax for the same quantity of silver, we learn without further trouble how much corn exchanges for so much flax. The chosen commodity becomes a common denominator or common measure of value, in terms of which we estimate the values of all other goods, so that their values become capable of the most easy comparison.