This chapter summarizes what is known of Augustine's access to the text of the Nicomachean Ethics (N.E.) and, in general, Aristotle's naturalistic account of human agency and happiness. It considers the impact of the Aristotelian conception of eudaimonia on Augustine's own treatment of human beatitude. The appropriation of this Aristotelian notion of eudaimonia is already evident in Augustine's early philosophical dialogues. Yet, in the same works one also finds a transformation and extension of Aristotle's philosophical conception of happiness. The chapter provides a paradigmatic account of the role Aristotle's ethics played in Augustine's thought. Among Latin Christians of the fourth century, Aristotle's reputation was largely that of a dialectician. Aristotle provided the necessary ontological connection in N.E., where he establishes the nature of the highest human good on the foundation of a functional analysis of human nature in terms of the capacity for rational activity.

This chapter deals with John Locke's teaching and his theory. The real ground of Locke's teaching is found in his understanding of the conditions of human happiness. Locke gives us two arguments that profess to explain how we know that we are governed by the law of nature, and part of what that law requires of us. Locke's awareness of inequality of parts leads him to revise the ground of the teaching of the law of nature regarding "the equality, which all men are in, in respect of jurisdiction or dominion one over another". Locke provides as little evidence for his divine workmanship argument as he does for his argument from equal talents. Locke's treatment of the parental desire to have children, "propagating their kind, and continuing themselves in their posterity", is similar to Aristotle's. Locke shows that nature by itself is too ambiguous to guide human life.

This chapter explains what Aristotle intends by the essentially "political" orientation of the activity of virtue, that is, of the activity constituting human happiness. Aristotle holds that to think assertively of something as being good is to be moved thereby toward it: this being moved is part of or an immediate effect of that thought itself. Due to the essential connection to motivation implied in the very act of understanding something good as good for oneself as a human being, this is a special sort of understanding. Aristotle's analyses and arguments in the Nicomachean Ethics about virtue and its place in a well-lived life. Aristotle reasonably thinks that that way of common living is impossible without the possession and use of the full knowledge of political science. His account in the Politics of the polis "as it exists according to nature" describes such a community.