The relation of natural value to exchange value is clear. Natural value is one element in the formation of exchange value. It does not, however, enter simply and thoroughly into exchange value. On the one side, it is disturbed by human imperfection, by error, fraud, force, chance; and on the other, by the present order of society, by the existence of private property, and by the differences between rich and poor,--as a consequence of which latter a second element mingles itself in the formation of exchange value, namely, _purchasing power_.[79] [Italics mine.]
This _purchasing power_ can only be either the inaccurate name of the English School for value itself, or else a consequence of the possession of goods which have value in the sense in which Wieser uses the term value, in the note on page 53 of his _Natural Value_ already quoted.[80] The circle becomes still more explicit in Hobson.[81] Hobson attempts to coördinate the Austrian theory with the older cost theory, and in this connection gives a table analyzing the forces that lie back of value, or "importance," from the supply side, and from the demand side. And there, apparently oblivious of the obvious circle, he places "purchasing power" as one of the ultimate factors on the demand side! If the Austrian analysis attempt nothing more than the determination of particular prices, one at a time, on the assumption that the transactions are, in each particular case, so small as not to disturb the marginal utility of money for each buyer and seller, and on the assumption that the values and prices of all the goods owned by buyers and sellers are already determined and known, except that of the good immediately in question, it is clear that it but plays over the surface of things. If it attempt more it is involved in a circle.
[76] The extreme abstraction of the utility school is made very clear by Pareto, _op. cit._, introductory chapter. He is concerned only with "the science of ophelimity" (p. 6), and ophelimity is a "wholly subjective quality" (p. 4).
[78] But as later indicated (_infra_, chap. XIII), the apparent simplicity of his analysis simply covers up, and does not eliminate, the complexity of the situation.