2. The other attempts at solution of the problem do not go beyond suggestions. In Bohm-Bawerk alone (Werth, p. 56) is there a more detailed statement, -- and it professes only to point out the direction in which probably the solution of the problem might be sought -- "To measure the share which each one of several co-operating factors takes in producing the common product."Bohm-Bawerk, speaking first of some less important cases of "complementariness," establishes firmly the fundamental maxim that no element in a group which admits, firstly, of a separate employment outside the group, and which, secondly, may be replaced at the same time in the group by other goods of the same nature -- obtained from some outside source -- can receive a value higher than its "substitution value." By substitution value he means "that which is derived from the decrease of utility in those branches of production from which the substituted goods are procured." Of such a nature are, e.g., the bricks destined for housebuilding. If some cartloads of these are destroyed, it will not hinder the building, as they are simply replaced by others.
This proposition Bohm-Bawerk applies to the cases of productive complementariness, dividing the total amount of complementary production goods into two categories. Of these, one -- which includes the overwhelming majority -- contains those goods which, as marketable wares, are "replaceable at will"; e.g., "the services of hired labourers, raw materials, fuel, tools, and so on." The other category -- which contains the minority --includes those productive elements which "cannot be replaced, or are difficult to replace; e.g. the piece of land which the peasant cultivates, mines, railway plant, factories, the activity of the undertaker himself with his high personal qualities." The value of those goods which belong to the first group is decided, in every case, through the other employments possible to them; it is, so far, fixed. This value is first deducted from the total return, and the residue then falls "to the member or members which cannot be replaced"; thus the "peasant ascribes it to his land, the mine-owner to his mine, the manufacturer to his factory, the merchant to his capacity.
"Similar ideas may be found more or less clearly stated by various writers; in the Ursprung des Werthes I have myself pointed to a similar solution. Probably we should not be far wrong were we to assume that the reason why so many writers have neglected to take up this problem of distribution, is that they supposed distribution in this sense to be as easily solved in theory as it is in practice. How is it, however, when several "unreplaceable" goods come together? Do not the mine and the activity of its owner, as employer, go together? And are not many -- indeed very many-replaceable goods often combined? The value of these, which, practically, can always be ascertained by referring to their secondary employment and valuation, must, theoretically, be first separated from the combination, as again the secondary employment itself always requires combination with complementary goods, -- but how can this be done unless the rules of distribution are known?
If these observations of Bohm-Bawerk can give no solution of the problem of imputation, they none the less contain an important and notable contribution towards its theory, for that could never be complete without recognising the distinction to which he has drawn attention. On this point see, in Book III, chap. xii, the examination of "cost goods and monopoly goods."
