 This is a point usually stressed by critics of libertarianism on the ground that property rights are conventional, not natural, and so cannot morally prohibit redistribution (Murphy &amp; Nagel 2002). This passage suggests that Friedman’s political philosophy does not include a natural right of private property as an impediment to redistribution. Second, Friedman sees his defense of the welfare state as a part of his non-ideal theory, not his ideal. He supports vouchers and the negative income tax