Economics wealth (capital) and a constant population size. Marxist (later, Marxian) economics descends from classical economics. It derives from the work of Karl Marx. The first volume of Marx's major work, "Das Kapital", was published in German in 1867. In it, Marx focused on the labour theory of value and the theory of surplus value which, he believed, explained the exploitation of labour by capital. The labour theory of value held that the value of an exchanged commodity was determined by the labour that went into its production and the theory of surplus value demonstrated how the workers only got paid
Biographies of Karl Marx (1925), Japanese (1930), Spanish (1932), and English (1935). Marx: Man and Fighter is a biography by Boris Nicolaievsky, first published in German in 1933. It was translated into English by Otto Mänchen-Helfen and published in 1936. Some subsequent English editions restore the notes, appendices, and bibliography omitted from the first English edition. Karl Marx: His Life and Environment is a 1939 biography of Karl Marx by Isaiah Berlin, in which Berlin argues that Marx's system of thought depends upon indefensible metaphysical presuppositions. Karl Marx: His Life and Thought is a 1973 biography of Karl Marx by political scientist David McLellan.