Robert Nozick

Robert Nozick was an American philosopher whose Anarchy, State, and Utopia argued for a minimal state — the libertarian alternative to Rawls's liberal egalitarianism. He defended individual rights as side constraints on state action and introduced the experience machine thought experiment.

Nozick's entitlement theory of justice held that a distribution is just if it arises from just acquisitions and voluntary transfers, regardless of its pattern. His subsequent work ranged widely, from epistemology (the tracking theory of knowledge) to the philosophy of life and a systematic philosophical investigation in The Nature of Rationality.