Karl Marx is the last of the great classical political economists, a school of thinkers who developed a theory of the economy as a social form which organizes production, distribution, exchange and consumption. Marx was interested in the historical development of all kinds of economic systems, but he is best known for his theory of capitalism, and his argument that capitalism sowed “the seeds of its own destruction” (Marx and Engels 1850), and would eventually give way to a new system called socialism.
Marx, Karl, and Engels, Friedrich. 1850. “Address of the Central Committee to the Communist League by Marx and Engels”. London, March. http://www.marxists.org/archive/marx/works/1847/communist-league/1850-ad1.htm.