Abstract

I defend a unified fictionalism about modality and mathematics. First, I defend each view separately against internal objections. Then, I attempt a unified fictionalism by giving an analysis of truth in fiction which is neither modal nor platonistic. Finally, I explore the prospects for nominalistic unified fictionalism. ;In the first chapter, I defend modal fictionalism: the view that statements about possible worlds are best understood as claims about the content of a fiction, the 'many-worlds story'. I address the Brock-Rosen objection that the fictionalist is a modal realist despite himself. I argue that Noonan's solution, the best response so far, is inadequate, and then offer an alternative fictionalist translation scheme for modal statements. ;In the second chapter, I defend mathematical fictionalism. Mathematical fictionalism is the view that mathematics is best understood as a fiction whose value is quite independent of its truth-value. Field argues for fictionalism in this sense by constructing nominalistic alternatives to standard physical theories. The aim is to establish that mathematical entities are 'dispensable for the purposes of science', and so to undermine the only reason we might have for believing in the literal truth of standard mathematics. I address an objection that the nominalization of current science would not suffice to establish the 'dispensability' of mathematical entities in the epistemologically relevant sense. I argue that there is a plausible interpretation of the indispensability argument according to which successful nominalization would establish that it is unreasonable to believe in mathematical entities. ;The most important challenge for any attempt at a unified fictionalism is to provide an account of truth in fiction that is neither implicitly modal nor implicitly platonistic. To this end, I offer in the third chapter an analysis of truth in a story which is based on a modified version of Walton's account of truth in fiction. ;A second challenge is to show that the timelessness and necessity of modal truth are compatible with the view that fictions are contingent and temporally restricted entities. In the final chapter, I argue this problem constitutes a genuine obstacle for a unified nominalistic fictionalism