Abstract

This is a three paper dissertation. ;for paper 1. Quine held that quantifying into modal contexts is illegitimate. It is sometimes thought that if he is right about this, then essentialist claims make no sense. Perhaps as a consequence of this thought together with the current prominence of essentialist views, there have been two good fairly recent attacks on Quine's argument against quantifying into modal contexts: Neale's revival of Smullyan's points and Kaplan's paper "Opacity". I first argue that Quine's view is not refuted by Neale or Kaplan. I next explain that nonetheless, essentialists need not surrender in the face of Quine's injunction against quantifying in. Quine's work does not rule out the intelligibility of essentialist theses; it does however issue a challenge to explain the mysterious notion of metaphysical necessity. ;Abstract for paper 2. I examine the case that has been made for origin essentialism and find it wanting. I focus on the arguments of Salmon and Forbes. Like most origin essentialists, they have been concerned to respect the intuition that slight variation in the origin of an artifact or organism is possible. But, I argue, both of their arguments fail to respect this intuition. Salmon's argument depends on a sufficiency principle for crossworld identity, which should be rejected, if---as Salmon concedes---a given artifact might have been originally made from slightly different material. Similarly, Forbes's argument succeeds only if essentially the same argument can be used to establish a claim that---by his own admission---is too strong, namely that no variation, however slight, in an organism's origin is possible. ;Abstract for paper 3. Chisholm's Paradox suggests that origin essentialism is incompatible with the view that some variation in the origin of a given thing is possible. Since the latter view is strongly supported by intuition, origin essentialists have been eager to offer solutions to the paradox. In this paper I look at three allegedly different solutions to the paradox: Forbes's, Salmon's, and Lewis's. I give new criticisms of Forbes's view and offer new defenses of what I call the "Salmon-Lewis solution"