Das Kapital sciences published before 1950. In "Das Kapital" (1867), Marx proposes that the motivating force of capitalism is in the exploitation of labor, whose unpaid work is the ultimate source of surplus value. The owner of the means of production is able to claim the right to this surplus value because he or she is legally protected by the ruling regime through property rights and the legally established distribution of shares which are by law only to be distributed to company owners and their board members. The historical section shows how these rights were acquired in the first place chiefly through
Karl Marx value advocated by David Ricardo. The work was enthusiastically received, and the edition sold out quickly. The successful sales of "A Contribution to the Critique of Political Economy" stimulated Marx in the early 1860s to finish work on the three large volumes that would compose his major life's work – "Das Kapital" and the "Theories of Surplus Value", which discussed the theoreticians of political economy, particularly Adam Smith and David Ricardo. "Theories of Surplus Value" is often referred to as the fourth volume of "Das Kapital" and constitutes one of the first comprehensive treatises on the history of economic thought.