This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Property is theft is one of the most quoted and least understood sentences in political philosophy, mostly because it is usually repeated without the distinction Pierre-Joseph Proudhon built the whole argument of What Is Property? (1840) around. He was not attacking the idea that a person can rightfully hold and use a thing. He was attacking a narrower and, in his account, much newer legal invention: the right to draw an income, rent, interest, dividend, from a holding without working it yourself, purely because the law recognizes your title to it.
Proudhon called the first kind of holding possession and defended it without qualification. A farmer who works his own field, a craftsman who owns his own tools, a family that lives in its own house, all hold possession in his sense, and mutualism, the economic system he proposed in place of both private capitalism and state socialism, was built entirely around protecting exactly this kind of possession. What he called property, and condemned as theft, was the second kind: land held by an absentee landlord who collects rent from tenants who do the actual farming, capital lent at interest by someone who contributes no labor to what the loan finances, a factory owned by a shareholder who never sets foot on its floor. In each case, Proudhon argued, income flows to the titleholder not because of anything productive the titleholder does, but purely because the law lets one person claim a portion of the value another person's labor creates. That, and only that, was the theft.
The positive proposal built on this distinction was mutualism: workers organized into producer and credit cooperatives, exchanging goods and extending credit to one another directly, without a landlord, a capitalist, or a central planning state standing between them and the value they created. It put Proudhon at odds with both wings of the emerging left of his day, too committed to individual possession and free exchange to satisfy the state socialists who wanted collective ownership run through central planning, and too hostile to rent, interest and profit to satisfy the liberal defenders of capital he was writing against in the first place. The sentence outlived the argument that produced it, quoted by people on every side of debates Proudhon himself would have wanted no part of, but the book itself is a far more careful piece of reasoning than the slogan pulled from its title ever lets on.