Socialism: Utopian and Scientific of thousands of copies. Throughout the decade of the 1860s, Karl Marx, close personal friend and political associate of Friedrich Engels, dedicated himself to the study of economics, culminating in the publication of the first volume of "Das Kapital" in 1867. Marx's lengthy and ponderous volume was extremely difficult for the average to penetrate, however, leading Engels to suggest to Marx in a letter of September 16, 1868 that a short popularized version of "Das Kapital" for a working class audience was urgently needed. "If it is not written, some Moses or other will come along and do it and
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.