Pierre-Joseph Proudhon (French pronunciation: [pjɛʁ ʒɔzɛf pʁudɔ̃]; 15 January 1809 – 19 January 1865) was a French politician, mutualist philosopher and socialist. He was a member of the French Parliament, and he was the first person to call himself an "anarchist". He is considered among the most influential theorists and organisers of anarchism. After the events of 1848 he began to call himself a federalist. He considered the Spanish politician Juan Donoso Cortés to be a personal adversary, since their belief systems were so diametrically opposed.
Proudhon, who was born in Besançon, was a printer who taught himself Latin in order to better print books in the language. His best-known assertion is that Property is Theft!, contained in his first major work, What is Property? Or, an Inquiry into the Principle of Right and Government (Qu'est-ce que la propriété? Recherche sur le principe du droit et du gouvernement), published in 1840. The book's publication attracted the attention of the French authorities. It also attracted the scrutiny of Karl Marx, who started a correspondence with its author. The two influenced each other: they met in Paris while Marx was exiled there. Their friendship finally ended when Marx responded to Proudhon's The System of Economic Contradictions, or The Philosophy of Poverty with the provocatively titled The Poverty of Philosophy. The dispute became one of the sources of the split between the anarchist and Marxist wings of the International Working Men's Association. Some, such as Edmund Wilson, have contended that Marx's attack on Proudhon had its origin in the latter's defense of Karl Grün, whom Marx bitterly disliked but who had been preparing translations of Proudhon's work.
Proudhon favored workers' associations or co-operatives, as well as individual worker/peasant possession, over private ownership or the nationalization of land and workplaces. He considered that social revolution could be achieved in a peaceful manner. In The Confessions of a Revolutionary Proudhon asserted that, Anarchy is Order Without Power, the phrase which much later inspired, in the view of some, the anarchist circled-A symbol, today "one of the most common graffiti on the urban landscape." He unsuccessfully tried to create a national bank, to be funded by what became an abortive attempt at an income tax on capitalists and stockholders. Similar in some respects to a credit union, it would have given interest-free loans.