The idea of spontaneous order (or more accurately emergent order) was worked out by Proudhon. His motto "Liberty, not the daughter, but the mother of order" was used by Benjamin Tucker on the masthead of his anarchist periodical "Liberty."

Proudhon's economics was basically the same as Josiah Warren's. It held that labor was the only proper source of wealth or justification for property, and assumed the Labor Theory of Value in a normative sense. Proudhon, unlike Warren, emphasized the idea of federation, and was generally less averse to associations. Proudhon, like Warren, advocated the use of debt notes denominated in labor time for monetary purposes. While Warren started small and proved the viability of these notes at least on a local level, Proudhon had grander schemes of a national "mutual bank," and never successfully implemented his idea. Ironically for a self-labelled anarchist, Proudhon sought to use the French state as a source of startup capital.

Being working-class himself, a printer by profession, Proudhon tried to appeal to the working people and the proletarian mystique. In his day, "socialism" (so-called) was young and not yet dominated by statists. Proudhon and Karl Marx, friendly early on, soon parted ways due to the incompatability of Proudhon's anti-state and anti-authoritarian core and Marx's proposed capture and use of state power to achieve socialism. This anarchist versus authoritarian socialism schism would continue for half a century, with Bakunin succeeding Proudhon as the libertarian champion.

Proudhon was rather unique among anarchists, in that he was culturally conservative. He opposed equality for women, and was reputedly something of a misogynist. He was very nationalistic about France, and an ardent anti-Semitic. For these and other reasons, the ideological leadership of the anarchist movement in Europe soon changed to the Russian Michael Bakunin, though Proudhon remained the well-respected "godfather" of European anarchism.

Proudhon's anarchist legacy gets mixed marks. Although a great proselytizer, his proclivity for socialist class war notions and his catering to vulgar proletarianism has, in hindsight, given anarchism a bad name. To this day, many associate anarchism with braindead anti-capitalism rather than principled anti-statism. But to be fair, the blame for this should probably fall on his followers and later socialists who appeal to his name rather than Proudhon himself.