Rawls argues that behind the veil of ignorance, the parties to the original position would agree on two principles of justice, arranged in lexical priority (the first must be fully satisfied before the second applies).
The First Principle (Equal Liberty): Each person is to have an equal right to the most extensive total system of equal basic liberties compatible with a similar system of liberty for all.
The Second Principle (Difference Principle and Fair Equality of Opportunity): Social and economic inequalities are to be arranged so that they are both (a) to the greatest benefit of the least advantaged members of society (the difference principle), and (b) attached to offices and positions open to all under conditions of fair equality of opportunity.
The lexical priority of the first principle means that basic liberties (freedom of conscience, speech, assembly, the rule of law) cannot be traded off against social and economic gains. A society cannot justifiably restrict political liberties to improve economic outcomes. The equal basic liberties must be secured first.
The difference principle is Rawls''s most original and most discussed contribution. It says that inequalities of wealth and income are just only if they benefit the least advantaged members of society. This is not a principle of strict equality: Rawls acknowledges that some inequalities can be justified if they create incentives that improve the overall productivity of the economy in ways that benefit even the worst-off. A society in which everyone is equally poor is not more just, on Rawls''s account, than one with inequality, if the inequality is what generates the resources that improve the position of the least advantaged.
But the difference principle is demanding. It is not enough that the least advantaged are better off in absolute terms than they would be under equality. They must be as well off as they could possibly be under any feasible arrangement. An inequality that benefits the worst-off by $1 is just on this principle; an inequality that benefits the wealthy by $1,000,000 while benefiting the worst-off by $0.50, when an alternative arrangement would have benefited the worst-off by $1, is unjust on this principle.
The difference principle is grounded in Rawls''s argument about the arbitrariness of natural talents. People who are more talented, more intelligent, or better endowed by nature did not earn those advantages: they are the product of what Rawls calls the ''natural lottery.'' Similarly, people born into more privileged social circumstances did not earn those advantages either. It follows that no one has a moral claim to the full product of their natural advantages. The talents of individuals are, in a sense, a ''common asset'': the naturally talented can use their talents to improve their own position, but only if doing so also benefits the least advantaged. This argument is at the center of Rawls''s dispute with Nozick, who argues in Anarchy, State, and Utopia (1974) that taxing the naturally talented for the benefit of others amounts to forced labor and a violation of self-ownership.
Quick reflection
Rawls argues that natural talents are, in a morally relevant sense, arbitrary and that the naturally talented have no full claim to the fruits of those talents: they are entitled to keep what is left after using their talents to benefit the least advantaged. Nozick responds that this is a violation of self-ownership: your talents are yours, not society''s. Think about this dispute in concrete terms. If you have a skill or talent that earns you significantly more than others, do you feel that you have a moral claim to the full return on that talent? Or does the fact that you did not choose to be born talented (or into circumstances that allowed the talent to develop) affect the strength of your claim? And does your answer depend on how you think about the relationship between the self and its natural endowments?