The Logic of Conceivability

Talk by Bjørn Jespersen (Utrecht)

Bjørn Jespersen on Fregean semantics: LoC seminar: Wed, Oct 31, 2018, 2 pm-4pm at the ILLC
Location: F1.15
Time: 2 pm-4pm
Title: 'Vulcan revisited: is the  F  an  F ?'

Abstract: This paper shows how my broadly Fregean formal semantic theory, upon amendment, is able to solve three problem cases that are variations of the sentence "The  is an  F ". The amendment is the novel notion of so-called  hyperoffices . These are fine-grained modes of presentation or persons-in-intension and serve to logically model 'impossible individuals', which are, naively speaking, people who could not possibly exist. Hyperoffices are required for the third of the problem cases, whereas standard individuals-in-intension (so-called  offices) suffice for the first two cases. My theory is Tichý's Transparent Intensional Logic (TIL). I apply my amended version of TIL against the two neo-Meinongian theories of Zalta's object theory (OT) and Priest's modal Meinongianism (MM), which are contingently or necessarily non-existent individuals. Furthermore, the sentence "The  F is an  F " arguably lends itself to two importantly different readings. On one reading, property  F is predicated of the object, if any, that is the unique instance of  F . On the other reading, a necessary relation obtains between  F and the condition for being the unique  F . OT and TIL have each their own way of capturing these two readings, whereas MM denies that "The  F  is an  F "states a necessary truth. The main result of this paper is that there is a broadly Fregean theory that fares well on typically Meinongian territory, namely cases where the unique  F is non-existent .


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