To the Austrian economists we owe a rational theory of costs which gives the money-outlay concept more than a merely empirical basis. First, they see in costs not causes, but results. Value causation comes ultimately, not from the side of supply, but from the side of demand. I shall not now undertake a criticism of their explanation of demand. I have elsewhere criticised their confusion of demand-curves and utility-curves, and pointed out that marginal utility gives no explanation of demand. I shall recur to the utility theory of value at a later point. For the present, it is enough to point out that the Austrian theory of costs is independent of their utility vagaries, and rests best on the notion of supply and demand, as expressed in the modern curves, with the assumption of a fixed value of the money-unit. Costs consists of entrepreneur money outlay of various kinds, chiefly wages, interest, and rent. Rent is, for the Austrians, as much a cost as any other item of entrepreneur outlay. But these items of cost are not ultimate data. They are rather reflections of the positive values of the products. Value runs from finished product to agents of production, labor, and instrumental goods, and land. Avoiding needless complications from a discussion of interest as a factor in cost--a doctrine on which the Austrians, say Wieser and Boehm-Bawerk, are not agreed,--it is enough to point out that high wages or high rents, which limit production in any given industry or establishment, are high _because_ the land and labor in question have _alternative_ uses, because other industries, or other competitors in the same industry, bid for them. Cost-curves, then, are reflections of demand-curves. The cost-curve of wheat, _e. g._, is what it is because of the demand-curve for corn, for cattle, and for every other commodity that could be produced with the same labor and land. Cost doctrine thus becomes part of the general doctrine of supply and demand, and runs in pecuniary terms, assuming money, and a fixed value of money, and hence is incapable of serving as a theory of the value of money itself. That some vaguer form of cost doctrine, where the unit of cost is, not money, but some composite commodity of things used in the production of the standard money metal, or a unit of abstract value, might be worked out, is doubtless true. Gold production, like other industry, is part of the general economic scheme, and there is some sort of equilibrium reached which draws labor and capital now away from, and now back to, the gold mine. To bring this equilibrium into the general scheme of the modern theory of costs, however, in terms precise enough to make a satisfactory theory of the value of money, is a thing which has not so far been done, and I do not have high hopes of its early accomplishment. In any case, such a theory must rest upon a positive theory of value. Cost doctrine is negative, and can never be fundamental.[57] CHAPTER IV