Dilemmas of Rawlsian Opportunity

John Rawls's repeated assertions that the basic structure of society creates profound and inevitable differences in life prospects for people born in different starting places seems to contradict his assertions that, under fair equality of opportunity, a person's life prospects would not be affected by class of origin for those similarly endowed and motivated. This seeming contradiction seems to be resolved by Rawls's apparent belief that class of origin inevitably affects motivation. This reconciliation leaves us with a very weak conception of "fair equality of opportunity." Should Rawls have advocated something stronger? Within the constraints of his theory of justice nothing stronger seems possible. Still, his theory harbors highly implausible sociological assumptions. A more plausible sociology requires us to reject distributive justice in favor of contributive justice.