Although Rothbard adopted Ludwig von Mises' deductive methodology for his social theory and economics, he parted with Mises on the question of ethics. Specifically, he rejected Mises' conviction that ethical values remain subjective and opposed utilitarianism in favor of principle-based, natural law reasoning. In defense of his free market views, Mises employed utilitarian economic arguments aimed at demonstrating that interventionist policies made all of society worse off. On the other hand, Rothbard concluded that interventionist policies do in fact benefit some people, including certain government employees and beneficiaries of social programs. Therefore, unlike Mises, Rothbard argued for an objective, natural-law basis for the free market. He called this principle "self-ownership", loosely basing the idea on the writings of John Locke and also borrowing concepts from classical liberalism and the anti-imperialism of the Old Right.