The claim that human agents are vulnerable to tragic conflict, situations in which one cannot help but do wrong, is a commonplace in contemporary moral philosophy. This book draws on Thomas Aquinas’s moral thought in order to delineate an alternative view. While affirming that the human good can be attained only through difficulty, including the difficulty of moral conflict, it argues that Aquinas’s understanding of a natural, hierarchical ordering of human goods allows for the rational resolution of moral conflict in a way that avoids tragic necessity.