Socialism refers to a broad set of economic theories of social organization advocating state or collective ownership and administration of the means of production and distribution of goods, and the creation of an egalitarian society. Newman, Michael. (2005) Socialism: A Very Short Introduction, Oxford University Press, ISBN 0-19-280431-6 Modern socialism originated in the late nineteenth-century working class political movement. Karl Marx posited that socialism would be achieved via class struggle and a proletarian revolution, it being the transitional stage between capitalism and communism.

Socialists mainly share the belief that capitalism unfairly concentrates power and wealth into a small section of society who control capital, and creates an unequal society. All socialists advocate the creation of an egalitarian society, in which wealth and power are distributed more evenly, although there is considerable disagreement among socialists over how, and to what extent this could be achieved.

Socialism is not a discrete philosophy of fixed doctrine and program; its branches advocate a degree of social interventionism and economic rationalization, sometimes opposing each other. Another dividing feature of the socialist movement is the split on how a socialist economy should be established between the reformists and the revolutionaries. Some socialists advocate complete nationalization of the means of production, distribution, and exchange; while others advocate state control of capital within the framework of a market economy. Social democrats propose selective nationalization of key national industries in mixed economies combined with tax-funded welfare programs; Libertarian socialism (which includes Socialist Anarchism and Libertarian Marxism) rejects state control and ownership of the economy altogether and advocates direct collective ownership of the means of production via co-operative workers' councils and workplace democracy.

In the 1970s and the 1980s, Yugoslavian, Hungarian, Polish and Chinese Communists instituted various forms of market socialism combining co-operative and State ownership models with the free market exchange. This is unlike the earlier theoretical market socialist proposal put forth by Oskar Lange in that it allows market forces, rather than central planners to guide production and exchange. Anarcho-syndicalists, Luxemburgists (such as those in the Socialist Party USA) and some elements of the United States New Left favor decentralized collective ownership in the form of cooperatives or workers' councils.

Historical precedents

Socialist thought and organization predate Socialism as ideology, which emerged in the first-half of the nineteenth century. In fifth-century Persia, the Mazdak proto-socialists challenged Noble and Clerical privilege, criticized private property to achieve an egalitarian society. In sixteenth-century literature, Utopia (1519), by Thomas More, posits a socialist utopia. In the nineteenth century, as socialist thought coalesced to formal ideology and programme, William Morris denoted the priest John Ball (1331–1381) as the first socialist in England, for having been a leader of the Peasants' Revolt (1381); moreover, Ball is credited the saying: When Adam delved and Eve span, who was, then, the gentleman? In the mid-seventeenth century English Civil War, the contemporary political socialists include the Levellers, and the Diggers, advocating common tenancy of land. In eighteenth-century France, Enlightenment criticism of enforced socio-economic inequality is Jean Jacques Rousseau's gist in the Social Contract, that begins: Man is born free, and he is everywhere in chains. After the French Revolution, François Noël Babeuf advocated common land-ownership and politico-economic equality of Citizens.