The Department of Philosophy is hosting a talk on the philosophy of language being given by Zsófia Zvolenszky of the Slovak Academy of Sciences and Eötvös Loránd University in Hungary: "A common problem for possible-worlds analyses of deontic and fictional discourse." This will be taking place on Monday, April 11, from 3:15 PM to 5:00 PM in room 418 of the Jackman Humanities Building.
In my talk, I will bring together considerations from formal semantics and philosophy of language about two seemingly very different types of discourse: deontic modal discourse (about what is necessary and possible according to a certain set of rules, for example, rules of etiquette or U.S. traffic laws), and discourse about fiction (claims like 'Anna Karenina is Russian', true in the work of fiction but not true simpliciter). My aim is to draw out commonalities of these two types of discourse, and lessons they hold for one another. Specifically, I focus on (i) a common problem that affects influential possible-worlds-based accounts of the two types of discourse; and (ii) the advantages of an alternative, operator-based approach to the two types of discourse. I'll say a bit more about these in reverse order.
A fiction-operator ("in/according to the relevant work of fiction") is widely used in analyses of fictional discourse; I argue that an analogous corpus-operator ("according to the relevant corpus of rules/laws") has advantages when accounting for deontic modal discourse. Crucially, neither operator should be cashed out in terms of truth with respect to possible worlds—for short, neither should be pw-based. The reason: a thorny problem (about intuitively false deontic modal claims that nonetheless come out as logical truths: for example, many claims of the form ‘if p then it ought to be that p). I (and others) have been discussing this problem over the past decade and a half in the context of deontic modal discourse, showing that it afflicts a benchmark pw-based analysis of modality due to Angelika Kratzer (she discusses the problem in her 2012 book Modals and Conditionals). I will argue that the thorny problem is even more general than previously thought (indeed applicable to deontic claims that aren’t conditional) and calls for giving up a basic tenet of pw-based analyses of deontic modality (like Kratzer’s): that the universal truth of p across a selected set of possible worlds is sufficient for ‘it ought to be that p’ to be true. A corpus-operator—if it steers clear of possible worlds—promises to avoid the various versions of the thorny problem at hand. Yet if we look to fashion the corpus-operator based on its far more widely discussed cousin, the fiction-operator, we find that one prominent approach to it, David Lewis’s (in his classic 1978 "Truth in Fiction"), gives a pw-based account of the fiction-operator. I argue that it is well to steer away from a Lewisian approach in the fictional discourse realm due to an analog of the thorny problem already familiar in the deontic modal discourse realm.
My conclusion is that there are reasons—in many ways parallel reasons—for adopting a non-pw-based operator approach to analyzing fictional discourse as well as deontic modal discourse.