Avicenna on Essence: A Historico-Philosophical Examination

The notion of essence is arguably one of the cornerstones of Avicenna’s philosophical system. It performs important functions in his metaphysics, epistemology, theology, and even science. In this study, I examine and evaluate the metaphysical functions that Avicenna attributes to essence. One function that essence performs in Avicenna’s metaphysics is explaining the interrelated phenomena that are commonly discussed under the problem of universals, namely, the resemblance phenomenon, the one-over-many phenomenon, and the categorization phenomenon. Additionally, in Avicenna’s metaphysics, essence serves as the underlying substratum of individuals. Thus, in Avicenna’s view, each individual is an essence particularized in a certain way and the bundle of accidents that the particularized essence holds. Moreover, in Avicenna’s metaphysics, (metaphysical) modality is grounded in essence. For example, the necessity that human beings are rational is grounded in facts about the essence of humanity. However, Avicennian essence cannot perform some of these functions unless it is shared, in a real sense of the word, by its instances, and it is not clear at all in what real sense Avicenna takes essence to be shared by them. On the one hand, he rejects Platonic and Aristotelian realisms about essence, the two standard accounts of how essence is shared by its instances. On the other hand, it is unclear that his alternative account(s) of essence renders essence genuinely common. Drawing on some of Avicenna’s own ideas, I propose to solve the problem by understanding Avicennian essence and its relationship with its instances in terms of the determinable/determinate distinction. On this understanding, Avicennian essence is an extramental, determinable entity whose maximally specific determinates are its instances. Although this realist account is not explicitly endorsed by Avicenna, it is built on some of his ideas.