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A TREATISE ON MONEY

BK. II

problems of Price-Levels. There is nothing left ofthe conception under criticism over and above oneof the Currency Index-Numbers already defined,which is, like all other Price Indexes, the price of acomposite commodity.

The Jevonian conception would have been in-tellectually delightful and of great scientific con-venience if it had been based on a true analysis.It is one of several quasi-mathematical economicconceptions, borrowed by analogy from the physicalsciences, which seemed likely to be so fruitful whenthey were first devised fifty or sixty years ago, butwhich have had to be discarded on further reflection,in whole or in part.