Alan Gewirth begins by distinguishing two models of self-fulfillment - aspiration-fulfillment and capacity-fulfillment - and shows how each of these contributes to the intrinsic value of human life. He then distinguishes between three types of morality - universalist, particularist, and personalist - and shows how each contributes to the values embodied in self-fulfillment. Building on these ideas, he develops a 'dialectical' conception of reason that shows how human rights are central to self-fulfillment. Gewirth also argues that self-fulfillment has a social as well as an individual dimension: that the nature of society and the obstacles that disadvantaged groups face affect strongly the character of the self-fulfillment that persons can achieve.