This course is the first of a two-semester sequence in which we will examine metaphysics from within the Aristotelian-Thomistic tradition. In order to explore just what metaphysics is, we will engage Aristotle’s texts, guided by St. Thomas’s commentaries, as well as writings by St. Thomas himself. In the first semester, we will begin with Aristotle’s Categories. We will then consider Thomas’s introduction to his commentary on Aristotle’s Metaphysics, as well as parts of several books of the Metaphysics itself: Alpha, Alpha elasson, Gamma, Delta, Epsilon, and Zeta. We will then work through Thomas’s early work De ente et essentia as a way to draw together many of the themes considered through this semester. In particular, we will consider first philosophy as wisdom and as a science, Aristotle’s emphasis on causal explanations, and the fundamental theme of substance.