An exhaustive analysis of the errors and contradictions contained in Marx's theory of value (value). The author was one of the first to draw attention to the contradictions between volumes I and III of Capital. Without limiting himself to pointing out the internal inconsistency of Marx's theory, the author precisely points out the point at which the error penetrated the system, as well as the ways along which it spread and branched out. Having demonstrated the inconsistency of the theory of value developed by Marx and, consequently, the theory of surplus value, Bem- Bawerk destroyed the economic foundation of the theory of exploitation, depriving socialist political slogans of a “scientific” basis.