Abstract
In this paper I propose a notion of propria inspired by Aristotle, on which propria are non-essential, necessary properties explained by the essence of a thing. My proposal differs from the characterization of propria by Kit Fine and Kathrin Koslicki: unlike Fine, the relation of explanation on my account can’t be assimilated to a notion of logical entailment. In disagreement with Koslicki, I suggest that the explanatory relation at issue needs not be necessary. My account of essence is conceptually parsimonious: it illuminates the contribution of essence to explanation without relying on obscure notions such as Aristotelian form or identity.