Abstract
This chapter discusses central views and debates about essence in medieval scholastic philosophy. Topics discussed include medieval views on the distinction between essential and accidental features, individual essences and the knowability of essences. The chapter also examines central debates about essence in the period. In light of their commitment to Aristotelian hylomorphism scholastic authors debated whether the essences of material substances were constituted by their forms alone or if their essences also contained matter. A second key debate about essence focused on the question of whether there is a real distinction between the essence of a created substance and its existence. The debate was about whether in addition to its essence a creature was composed by a distinct actualizing principle through which the essence was the essence of a real being, rather than a merely possible one. The chapter presents and analyzes positions and arguments advanced in these debates.