Yet, if in this way capital were apprehended as "an historical category," as Rodbertus would say, there is at least the comfort in it all that it should leave a free field for Mr. Clark's measures of repression as applied to the discretionary management of capital by the makers of trusts. And yet, again, this comforting reflection is coupled with the ugly accompaniment that by the same move the field would be left equally free of moral obstructions to the extreme proposals of the socialists. A safe and sane course for the quietist in these premises should apparently be to discard the equivocal doctrines of the passage (pp. 306-311) from which this train of questions arises, and hold fast to the received dogma, however unworkable, that "capital" is a congeries of physical objects with no ramifications or complications of an immaterial kind, and to avoid all recourse to the concept of value, or price, in discussing matters of modern business. * * * * * The center of interest and of theoretical force and validity in Mr. Clark's work is his law of "natural" distribution. Upon this law hangs very much of the rest, if not substantially the whole structure of theory. To this law of distribution the earlier portions of the theoretical development look forward, and this the succeeding portions of the treatise take as their point of departure. The law of "natural" distribution says that any productive agent "naturally" gets what it produces. Under ideally free competitive conditions--such as prevail in the "static" state, and to which the current situation approximates--each unit of each productive factor unavoidably gets the amount of wealth which it creates,--its "virtual product," as it is sometimes expressed. This law rests, for its theoretical validity, on the doctrine of "final productivity," set forth in full in the _Distribution of Wealth_, and more concisely in the _Essentials_[12]--"one of those universal principles which govern economic life in all its stages of evolution."[13] In combination with a given amount of capital, it is held, each succeeding unit of added labor adds a less than proportionate increment to the product. The total product created by the labor so engaged is at the same time the distributive share received by such labor as wages; and it equals the increment of product added by the "final" unit of labor, multiplied by the number of such units engaged. The law of "natural" interest is the same as this law of wages, with a change of terms. The product of each unit of labor or capital being measured by the product of the "final" unit, each gets the amount of its own product.