Marx's critics often fling at him the reproach that he did not completely prove his labor theory of value, but merely decreed it as something obvious. Other critics have been ready to see some type of proof in the first pages of Capital, and they aimed their heavy artillery against the statements with which Marx opens his work. This is the approach of Bohm-Bawerk in his critique (Karl Marx and the Close of his System; Positive Theory of Capital). Bohm-Bawerk's arguments at first glance seem so convincing that one may boldly say that not a single later critique was formulated without repeating them. However, Bohm-Bawerk's entire critique stands or falls together with the assumptions on which it is built: namely, that the first five pages of Capital contain the only basis on which Marx built his theory of value. Nothing is more erroneous than this conception. In the first pages of Capital, Marx, by means of the analytic method, passes from exchange value to value, and from value to labor. But the complete dialectical ground of Marx's theory of value can only be given on the basis of his theory of commodity fetishism which analyzes the general structure of the commodity economy. Only after one finds the basis of Marx's theory of value does it become clear what Marx says in the famous first chapter of Capital. Only then do Marx's theory of value as well as numerous critiques of it appear in a proper light. Only after Hilferding's work [1] did one begin to understand accurately the sociological character of Marx's theory of value. The point of departure of the labor theory of value is a determined social environment, a society with a determined production structure. This conception was often repeated by Marxists; but until Hilferding's time, no one made it the foundation-stone of the entire edifice of Marx's theory of value. Hilferding deserves great praise for this, but unfortunately he confined himself to a general treatment of the problems of the theory of value, and did not systematically present its basis.
As was shown in Part I, on commodity fetishism, the central insight of the theory of fetishism is not that political economy discloses production relations among people behind material categories, but that in a commodity-capitalist economy, these production relations among people necessarily acquire a material form and can be realized only in this form. The usual short formulation of this theory holds that the value of the commodity depends on the quantity of labor socially necessary for its production; or, in a general formulation, that labor is hidden behind, or contained in, value: value = "materialized" labor. It is more accurate to express the theory of value inversely: in the commodity-capitalist economy, production work relations among people necessarily acquire the form of the value of things, and can appear only in this material form; social labor can only be expressed in value. Here the point of departure for research is not value but labor, not the transactions of market exchange as such, but the production structure of the commodity society, the totality of production relations among people. The transactions of market exchange are then the necessary consequences of the internal structure of the society; they are one of the aspects of the social process of production. The labor theory of value is not based on an analysis of exchange transactions as such in their material form, but on the analysis of those social production relations expressed in the transactions.
[1] "Bohm-Bawerks Marx-Kritik," Marx-Studien, Wien, 1904, and the previously cited article, "Zur Problemstellung der theoretischen Oekonomie bei Karl Marx," Die Neue Zeit, Stuttgart, 1904.