Very briefly. Marx (1818–1883) wrote to him after What is Property? (1840) was published and they became friends in Paris, where Marx was then living in exile. But Marx responded to Proudhon’s subsequent The Philosophy of Poverty (1847) with The Poverty of Philosophy (1880). The ensuing dispute divided the anarchists from the Marxists in the International Working Men’s Association. Proudhon also had a dispute with Mikhail Bakunin’s (1814–1876) followers, who objected to his idea of worker’s cooperatives and peasant ownership of land and factories after a peaceful revolution.