Original sentence: In the 19th century, Karl Marx’s contemporary, Carl Menger (1840–1921), proposed the “Theory of Subjective Wants”, wherein the behaviour of the market is explainable only in terms of the subjective wants of the buyer and the seller.In the opinion of Karl Marx, the theories of natural market-behaviour proffered by capitalist economists were products of the way the market functioned — by the volition and initiative of the buyers and sellers of commodities — not otherwise
Edited sentence: In the 19th century, Karl Marx’s contemporary, Carl Menger, proposed the "Theory of Subjective Wants", wherein the behaviour of the market is explainable only in terms of the subjective wants of the buyer and the seller.In the opinion of Karl Marx, the theories of "natural market-behaviour" proffered by capitalist economists were products of the way the market functioned — by the volition and initiative of the buyers and sellers of commodities — not otherwise.Yet, for Karl Marx, such a naïve theory of "market behaviour" was a product of commodity fetishism, which disconnected market exchange (trade) from the constraints upon trade imposed by the labour of the worker, by history, and by the social relations between the buyers and the sellers