Proudhon
French mutualist theorist (1809–1865), born in Besançon into a modest family of peasants and shopkeepers, self-taught, who worked as a printer before winning a scholarship that allowed him to study formally, and the first thinker in history to call himself an 'anarchist' — a term previously used only pejoratively — reclaiming it with defiant pride as his own label. His work that brought him immediate and scandalous fame, What Is Property? (1840), answers the title question with his most famous and incendiary formula: 'property is theft', a thesis that does not reject all forms of possession but specifically the property that generates income without labour — what he called 'property-sovereignty', which allows its owner to exploit the labour of others — while defending 'possession', a worker's right to use and enjoy the fruits of their own effort. He developed mutualism, an economic system based on reciprocity among independent producers, the establishment of interest-free popular credit banks to finance cooperatives and small producers, and the gradual replacement of the centralised state with voluntary federations of communes and self-managed professional associations — a vision that profoundly influenced Bakunin and all subsequent anarchism, though Proudhon himself rejected revolutionary violence and advocated gradual, peaceful change. His intellectual rivalry with Karl Marx, who harshly criticised his economics in The Poverty of Philosophy (1847) in response to Proudhon's book The System of Economic Contradictions, or the Philosophy of Poverty, marked the beginning of the lasting split between Marxist socialism and anarchist and libertarian traditions within the international labour movement.