Rawls himself says surprisingly little by way of justification of fair equality of opportunity. In his theory of justice, justice concerns are nested in strict lexical priority relations. First priority is assigned to a principle that demands equal basic liberties such as freedom of speech for all. Second priority goes to fair equality of opportunity, which is interpreted as a prerequisite for justified inequalities in the distribution of social primary goods, basic resources suitable for advancing a wide range of plans of life. Inequalities in people's holdings of primary social goods must (a) be attached to positions and offices open to all according to fair equality of opportunity and (b) must work to the maximal advantage of the least advantaged social group. In Rawls's system, (a) takes strict lexical priority over (b).  In broad terms, Rawls insists that fair equality of opportunity rules out improving the condition of the worst off by instituting practices that generate inequalities that fail to satisfy FEO.