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
Karl Marx move to Germany, Marx decided to emigrate to Brussels in Belgium in February 1845. However, to stay in Belgium he had to pledge not to publish anything on the subject of contemporary politics. In Brussels, Marx associated with other exiled socialists from across Europe, including Moses Hess, Karl Heinzen and Joseph Weydemeyer. In April 1845, Engels moved from Barmen in Germany to Brussels to join Marx and the growing cadre of members of the League of the Just now seeking home in Brussels. Later, Mary Burns, Engels' long-time companion, left Manchester, England to join Engels in Brussels. In mid-July 1845,