Karl Marx (1818-1883) was a German philosopher, historian, sociologist, and communist. Marx published The Communist Manifesto (1848) with Friedrich Engels and Das Kapital, a three-volume study of capital (1867-1883). Marx’s writing had considerable influence on intellectual, economic, and political history and theory. Marx’s core concept is that human society develops through class conflict. In capitalist societies this conflict is manifested in the tension between the ruling classes (the bourgeoise), who own the means of production, and the working classes (the proletariat), who are wageworkers. The theory of historical materialism argues that the internal tensions produced by capitalism mean that it will eventually collapse. Marx supported revolutionary change driven by the working class to dismantle capitalism and bring about a new socioeconomic system. The inequality and instability of capitalism would lead to the development of class consciousness among the working class, who would build a classless society characterized by free association of producers. This political system was called communism.