[150] I take pleasure in availing myself of the privilege which Professor W. A. Scott, of the University of Wisconsin, accords me, of quoting him to the effect that "such a conception of value [a value concept which makes the value of a commodity a quantity, socially valid, regardless of the individual holder of the coin or the commodity, and regardless of the particular exchange ratio into which the value quantity enters as a term] is absolutely essential to the working-out of economic problems." Professor Scott has been driven to this conclusion in the course of his studies in the theory of money. Dean Kinley expresses a somewhat similar view in his _Money_, p. 62. It is, of course, in the theory of money that the need for such a concept makes itself most acutely felt. But the same view is expressed by Professor T. S. Adams, from the standpoint of the statistician. See his article, "Index Numbers and the Standard of Value," _Jour. of Pol. Econ._, vol. X, 1901-02, pp. 11 and 18-19. [151] Even Professor H. J. Davenport finds a quantitative value concept necessary in places. For example, on page 573 of his _Value and Distribution_, he speaks of capital, considered as a cost concept, as standing "for the total invested fund of value, inclusive of all instrumental values, and of all the general purchasing power devoted to the gain-seeking enterprise." It might be unkind to remind him of his definition of value on page 569, and ask him what a "fund" of "ratio of exchange" might mean! And the notion of value as a quantity, instead of a ratio, is involved, as indicated in the text, in the term, "purchasing power," which he also uses in the passage quoted. This term, "purchasing power," as apparently a substitute for value, Professor Davenport uses in several instances, where the ratio notion clearly will not work: on page 561, "distribution of purchasing power," page 562, "redistribution of purchasing power," and page 571. I say "apparently," for I do not think Professor Davenport anywhere in the volume gives a formal definition of "purchasing power." [152] "Grundzuege," etc., Conrad's _Jahrbuecher_, 1886, pp. 5 and 478, n. [153] This line of argument, drawn from the usage of the economists in the treatment of other terms, and in the handling of problems, might be almost indefinitely expanded. Almost everybody has a quantitative value concept in mind when he is reasoning about practical problems. The trouble comes only when a value theory has to be constructed! _Cf._ the discussion of production as the "creation of utilities," _infra_ chap. XVIII. CHAPTER XII SOCIAL VALUE: THE THEORIES OF URBAN AND TARDE