At the center of all medieval Christian accounts of both metaphysics and ethics stands the claim that being and goodness are necessarily connected, and that grasping the nature of this connection is fundamental to explaining the nature of goodness itself. In that vein, medievals offered two distinct ways of conceiving this necessary connection: the nature approach and the creation approach. The nature approach explains the goodness of an entity by an appeal to the entity’s nature as the type of thing (...) it is, and the extent to which it fulfills or perfects the potentialities in its nature. In contrast, the creation approach explains both the being and goodness of an entity by an appeal to God’s creative activity: on this view, both a thing’s being and its goodness are derived from, and explained in terms of, God’s being and goodness. Studies on being and goodness in medieval philosophy often culminate in the synthesizing work of Thomas Aquinas, the leading Dominican theologian at Paris in the 13th century, who brought together these two rival theories about the nature of goodness. Unfortunately, few have paid attention to a distinctively Franciscan approach to the topic around this same time period. My dissertation provides a remedy to this oversight by means of a thorough examination of John Duns Scotus’s approach to being and goodness—an approach that takes into account the shifting tide toward voluntarism (both ethical and theological) at the University of Paris in the late 13th century. I argue that Scotus is also a synthesizer of sorts, harmonizing the two distinct nature approaches of Augustine and Aristotle with his own unique ideas in ways that have profound implications for the future of medieval ethical theorizing, most notably, in his rejection of both the natural law and ethical eudaimonism of Thomas Aquinas. After the introduction, I analyze the nature of primary goodness—the goodness that Scotus thinks is convertible with being and thus a transcendental attribute of everything that exists. There, I compare the notion of convertibility of being and goodness among Scotus and his contemporaries. While Scotus agrees with the mainstream tradition that being and goodness are necessarily coextensive properties of everything that exists, he argues that being and good are formally rather than conceptually distinct. I argue that when the referents of being and good are considered, both views amount to the same thing. But when the concepts of being and good are considered, positing a formal distinction does make a good deal of difference: good does not simply add something to being conceptually, but formally: it is a quasi-attribute of being that exists in the world independently of our conception of it. Thus Scotus’s formal distinction provides a novel justification for the necessary connection between being and goodness. Furthermore, I argue that Scotus holds an Augustinian hierarchy of being. This hierarchical ranking of being is based upon the magnitude or perfection of the thing’s nature. But since goodness is a necessarily coextensive perfection of being, it too comes in degrees dependent upon the type of being, arranged in terms of the same hierarchy. This account, while inspired by Augustine’s hierarchical nature approach, is expressed in terms of Aristotelian metaphysics. But this necessary connection between being and goodness in medieval philosophy faced a problem: Following Augustine, medievals claimed that “everything that exists is good insofar as it exists.”’ But how is that compatible with the existence of sinful acts: if every being, in so far as it has being, is good, then every act, insofar as it has being, is good. But if sinful acts are bad, then we seem to be committed to saying either that bad acts are good, or that not every act, in so far as it has being, is good. This first option seems infelicitous; the second denies Augustine’s claims that “everything that exists is good.” Lombard and his followers solve this problem by distinguishing ontological goodness from moral goodness and claiming that moral goodness is an accident of some acts and does not convert with being. So the sinful act, qua act, is (ontologically) good. But the sinful act, qua disorder is (morally) bad. Eventually, three distinctive grades of accidental or moral goodness will be applied to human acts: generic, circumstantial, and meritorious. I argue that Scotus follows the traditional account of Peter Lombard, Philip the Chancellor, Albert the Great, and Bonaventure in distinguishing ontological goodness from moral goodness, and claiming that only the former converts with being, while the latter is an accident of the act. Aquinas, in contrast, writing in the heyday of the Aristotelian renaissance, focuses instead on the role of the act in the agent’s perfection and posits his convertibility thesis of being and goodness in the moral as well as the metaphysical realm. Thus, when one begins a late medieval discussion with Aquinas, and then considers what Scotus says, it seems as though Scotus is the radical who departs from the conservative teachings of Aquinas. And this is just false: we need to situate both Aquinas and Scotus within the larger Sentence Commentary tradition extending back to Peter Lombard and his followers in order to understand their agreement and divergence from the tradition. Next, I turn the discussion to Scotus’s analysis of rightness and wrongness. I first explore the relationship between rightness and God’s will, and situate Scotus’s account within contemporary discussions of theological voluntarism. I argue Scotus holds a restricted-causal-will-theory —whereby only contingent deontological propositions depend upon God’s will for their moral status. In contrast to Aquinas, Scotus denies that contingent moral laws—the Second Table of the 10 Commandments (such do not steal, do not murder, etc.)—are grounded in human nature, and thus he limits the extent to which moral reasoning can move from natural law to the moral obligations we have toward one another. In conjunction with these claims, I argue that Scotus distinguishes goodness from rightness: An act’s rightness will depend on its conformity to either (1) a necessary moral truth or (2) God’s commanding some contingent moral truth. The moral goodness of an act, in contrast, involves right reason’s determination of the suitability or harmony of all factors pertaining to the act. In establishing this, also argue that much of the disparity among contemporary Scotus scholarship on the question of whether Scotus was a divine command theorist or natural law theorist should be directly attributed to a failure to recognize Scotus’s separation of the goodness of an act from the rightness of an act. (shrink)