John Rawls

In A Theory of Justice, published in 1971, Rawls asks us to imagine people choosing principles of justice from an original position behind a veil of ignorance. They do not know their class, talents, religion, or social status, so the choice is meant to be fair.

The difference principle says social and economic inequalities are acceptable only if they benefit the least advantaged members of society. It is one of Rawls's two principles of justice and became central to modern liberal political philosophy.

Robert Nozick challenged Rawls in Anarchy, State, and Utopia, published in 1974. Nozick defended a libertarian theory of rights and entitlement, making his book one of the most famous replies to A Theory of Justice.

Political Liberalism, published in 1993, responds to the problem of deep disagreement in democratic societies. Rawls shifted attention toward how citizens with different religious, moral, and philosophical views can still share a political conception of justice.