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The slave frees himself when, of all the relations of private property, he abolishes only the relation of slavery and thereby becomes a proletarian; the proletarian can free himself only by abolishing private property in general.

Karl Marx, Friedrich Engels, Philip Gasper (2005). “The Communist Manifesto: A Road Map to History's Most Important Political Document”, p.132, Haymarket Books
The slave frees himself when, of all the relations of private property, he abolishes only the relation of slavery and thereby becomes a proletarian; the proletarian can free himself only by abolishing private property