<P> Karl Marx acknowledged that "nothing can have value, without being an object of utility", but, in his analysis, "use - value as such lies outside the sphere of investigation of political economy", with labor being the principal measure of value under capitalism . </P> <P> The doctrines of marginalism and the Marginal Revolution are often interpreted as somehow a response to Marxist economics . However the first volume of Das Kapital was not published until July 1867, after the works of Jevons, Menger, and Walras were written or well under way (In 1874 Walras published Éléments d'économie politique pure and Carl Menger published Principles of Economics in 1871); and Marx was still a relatively minor figure when these works were completed . It is unlikely that any of them knew anything of him . (On the other hand, Hayek or Bartley has suggested that Marx, voraciously reading at the British Museum, may have come across the works of one or more of these figures, and that his inability to formulate a viable critique may account for his failure to complete any further volumes of Kapital before his death .) </P> <P> Nonetheless, it is not unreasonable to suggest that the generation who followed the preceptors of the Revolution succeeded partly because they could formulate straightforward responses to Marxist economic theory . The most famous of these was that of Böhm - Bawerk, Zum Abschluss des Marxschen Systems (1896), but the first was Wicksteed's "The Marxian Theory of Value . Das Kapital: a criticism" (1884, followed by "The Jevonian criticism of Marx: a rejoinder" in 1885). Initially there were only a few Marxist responses to marginalism, of which the most famous were Rudolf Hilferding's Böhm - Bawerks Marx - Kritik (1904) and Politicheskoy ekonomni rante (1914) by Никола́й Ива́нович Буха́рин (Nikolai Bukharin). However, over the course of the 20th century a considerable literature developed on the conflict between marginalism and the labour theory of value, with the work of the neo-Ricardian economist Piero Sraffa providing an important critique of marginalism . </P> <P> It might also be noted that some followers of Henry George similarly consider marginalism and neoclassical economics a reaction to Progress and Poverty, which was published in 1879 . </P>

Explain by using an example the concept of diminishing marginal utility