||The interplay of essentialism and modal logic is a major topic in the logic and metaphysics of modality. Quine 1953 argued that quantified modal logic (QML) entails essentialism, the view that an object can have a property essentially, independently of how it is referred to. Since he found essentialism to be unintelligible, Quine concluded that QML should be rejected. Kripke 1963 and Marcus 1967 have contributed to the rehabilitation of QML by showing how it can be made sense of within a suitable semantic framework. Others, such as Parsons 1969 and McKay 1975, have argued that QML is not committed to the thesis of essentialism in the way Quine thought. Now that the intelligibility of QML is no longer at issue, a central problem in the contemporary debate is whether the notion of essence can be understood in modal terms. A classical modalist analysis of essence is due to Moore 1920: x is essentially P iff x is necessarily P (or, in conditional form: iff x is necessarily P, if existent). This reduction of essence to pure QML has been found wanting by Fine 1994. A general argument against modal characterizations of essence has been proposed by Torza 2015. As a consequence, the Moorean definition has been mostly abandoned (but see Cowling 2013). Some proposals have emerged that attempt to understand essence by means of revisions or extensions of standard QML. Zalta 2006 and Wildman 2013 have proposed to reduce essence to a combination of modal and non-modal notions. Correia 2007 has put forward an analysis of essence carried out in a modal logic which is more fine-grained that standard QML. Fine 1995, 2000 has formulated a quantified intensional logic for the notion of essence.