Augustine has been neglected in contemporary moral philosophy, despite the rise to prominence of virtue-based approaches in ethics. This “virtue revival” has sparked extensive examination of ancient and medieval ethics, to the relative neglect of Augustine, who is an important figure in that tradition. This dissertation seeks to develop the outline of an Augustinian approach to ethics by bringing Augustine into contact with contemporary reflections on practical reason. In particular, it engages thinkers who seek to gain traction on issues of moral philosophy by examining the contours, requirements and presuppositions of successful human agency. The dissertation articulates an Augustinian understanding of practical reason by discussing ways that these debates can benefit from Augustine’s insight that all exercises of practical reason which fail to recognize that the human heart is restless until it rests in God are self-defeating.

The dissertation explores the usefulness of this Augustinian idea by examining the phenomenon of the defeasible goodness of the goods agents pursue in action. It suggests that the best way for agents to make sense of the defeasible goodness of good things is by rendering these goods commensurable in terms of the place they can play within a certain kind of “pilgrim” life described in the third chapter. However, the commensurability of goods must be understood as a result of practical deliberation, not a precondition of it. This approach requires taking seriously the possibility that practical reason comes along too late to be of any use. That is, agents typically possess the resources for successful deliberation only after making the relevant decisions. Chapter five discusses this problem, critiques an influential approach to it, and suggests an Augustinian approach to the problem.