'Communism' a theory or system of social organization based on the holding of all property in common, actual ownership being ascribed to the community as a whole or to the state...... in which all economic and social activity is controlled by a totalitarian state dominated by a single and self-perpetuating political party.
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'Socialism' a theory or system of social organization that advocates the vesting of the ownership and control of the means of production and distribution, of capital, land, etc., in the community as a whole.... procedure or practice in accordance with this (in Marxist theory) the stage following capitalism in the transition of a society to communism, characterized by the imperfect implementation of collectivist principles.