As for the why the conceptual scheme of economics is functionally indispensable to the life of bourgeois culture despite its inconsistencies and absurdities (by the way, Barbara Fields approaches the conceptual scheme of race in 19th century America in the same way), Mattick jr provides the following explanation in a later paper-"Theory as Critique: On the Argument in Capital" in New Investigations of Marx's Method. ed. Fred Moseley and Martha Campbell Humanities Press, 1997:
Here he grapples with the impossibility of understanding "the functioning of capitalism in terms of economic concepts, which nevertheless are experienced as 'natural' and fundamental categories of social life by those employ them."
He writes later:
"Having worked out the forms taken by surplus value (more correctly: the phenomena redescribed in terms of surplus value), Marx can then examine economic reality as it appears in 'vulgar' economic theory, as the production of wealth by the three factors of production, capital, land and labor, to which revenue accordingly (and justly) flows as profit (plus interest), rent and wages. The entire of his work [Capital] to this point has explosed ther reaity experienced in the form of these categories; here Marx is in a position to explain their power. For the trinity of economic factors acutally are the sources of their specific revenues 'in these that capital for the capitalist is a perpetual pumping machine for surplus labor, land for the landowner a permanent magent for attracting a part of the surplus pumped out by capital and finally labor athe constantly self renewing condition and menas for the worker to obtain a part of the value he has produced and hence a part of the social product measured by this portion of vlaue, under the heading of wages". The viability of economic discourse is in this way shown to depend on the fact that the 'capitalist mode of production, like every other constantly reproduces not only the material product but also the social economic relations, the formal economic determinants of its formation." Economic theory gains its plausibility from the conformity of its conceptual apparatus to the assumptions embodied in commercial calculations and contracts, and these assumptions maintain their power because people naturally attempt to carry out their lives within social relations they find themselves caught up in, of which the assumptions provide the structural terms. As Marx put it, in a concise statement of the culturally constructed character of social reality, "The specific shape in which the value components [of social wealth] confront one another is presupposed because it is constantly reproduced, and it is constantly reproduced because it is constantly presupposed.'" p. 84-85
The hold of economic discourse on professional social scientists has also been explained by the way its formalisation and mathematicization on the basis of the equi marginal principle enable the overcoming of physics envy. I believe it was John Bates Clark who also suggested that neo classical economics could be read as a conscious reply, point by by point, to Marx's theory. In his Origin of Economic Ideas Guy Routh provides some telling quotes from the founders of marginalism. For the conceptual incoherence of economic discourse, Mattick, jr. points to Oskar Morgenstern's critique in Journal of Economic Literature, 10:4 (Dec 1972)--which is not to say that game theory is better suited than marginalism to understand "why the reproduction of capital social relations involves a tendency to economic crisis, and that this, given the massive degradtation of working class life it entails, contains the possibility of social crisis."
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