Karl Marx (1818-1883) is regarded as the Father of Communism. He did not separately propose any theory of population, but his surplus population theory has been deduced from his theory of communism. Marx opposed and criticized the Malthusian theory of population.
According to Marx, population increase must be interpreted in the context of the capitalistic economic system. A capitalist gives to labor as wage a small share of labor's productivity, and the capitalist himself takes the lion's share. The capitalist introduces more and more machinery and thus increases the surplus value of labor's productivity, which is pocketed by the capitalist. The surplus is the difference between labor's productivity and the wage level. A worker is paid less than the value of his productivity. When machinery is introduced, unemployment increases and, consequently, a reserve army of labor is created. Under these situations, the wage level goes down further, the poor parents cannot properly rear their children and a large part of the population becomes virtually surplus. Poverty, hunger and other social ills are the result of socially unjust practices associated with capitalism.
Population growth, according to Marx, is therefore not related to the alleged ignorance or moral inferiority of the poor, but is a consequence of the capitalist economic system. Marx points out that landlordism, unfavorable and high man-land ratio, uncertainty regarding land tenure system and the like are responsible for low food production in a country. Only in places where the production of food is not adequate does population growth become a problem.