Neither does a machine, or an acre of wheat land, or goods in a wholesaler's warehouse. Exchange is a productive process, an essential part of the present process of production. Money is a tool which enormously facilitates this process. It has its peculiarities, no doubt. One of them is--and money is not unique in this as will later appear--that it must have _value_ from non-monetary sources[68] before it can perform its own special functions, from some of which it draws an increased value. But there seems to me to be nothing in the contention quoted from Professor Fisher, to justify setting money sharply off from all other things, or to justify the view that marginal utility is inapplicable to the value of money, if it be applicable to the value of anything at all that is not destined for immediate consumption. I do not believe that the marginal utility theory is valid for any class of goods, not even those for immediate consumption. Where marginal utility theory is,--as in the conventional text-book expositions--merely another name for supply and demand theory, it is, as already shown, not applicable to the value of money, and it is useful in the surface explanation of market-prices of goods. But where marginal utility theory really seeks to get at value fundamentals, it is precisely as valid for money as for goods of other sorts--invalid, in my judgment, in both places, and for the same reasons in both. Among the writers who would apply the utility theory to money, while still insisting that money, as such, has no utility, are Wieser, Schumpeter--who accepts Wieser's theory in its main outlines--and von Mises, who develops a notion very different from that of the other two. Wieser's doctrines are set forth in two expositions, separated by five years, the second representing a considerable development in his thought, though resting in part on the first. The first is an address upon the occasion of his accession to the professorship at the University of Vienna, in 1904, and is published in the _Zeitschrift fuer Volkswirtschaft, Sozialpolitik und Verwaltung_, vol. 13 entitled, "Der Geldwert und seine geschichtlichen Veraenderungen." The second is a discussion, partly written and partly spoken, "Der Geldwert und seine Veraenderungen" (written), and "Ueber die Messung der Veraenderungen des Geldwertes" (spoken), in _Schriften des Vereins fuer Sozialpolitik, Referate zur Tagung_, no. 132, 1909. For the purpose in hand, a brief statement of one or two points would suffice to show the futility of Wieser's effort to get an explanation of the value of money _via_ marginal utility, but I think that readers may be interested in a fuller account of Wieser's doctrine, just because it is Wieser's, and so shall undertake to give a more systematic account of it. For brevity, in the exposition which follows, I shall refer to the first article as "I," and to the second as "II."[69]