We are very happy to announce a guest talk, which will take place on Wednesday, July 17, 2 – 4 pm in IG 4.301.

Kai Wehmeier (UCI) will present „On Boxes and Quantifiers“.


Whether operations such as necessitation or universal quantification create extensional or intensional contexts depends on what counts as an extension. In „Pragmatics and Intensional Logic“ (1970), Montague proposes an asymmetric approach that makes the box an intensional but the standard first-order quantifier an extensional context. In this talk, I will investigate whether there are any formal grounds for such differential treatment of boxes and quantifiers. To this end, I develop some general theory of notational variance between interpreted formal languages. I show that extant results do indeed point to a lack of complete correspondence between modal operator and ordinary first-order languages. Nevertheless, a single notational innovation reveals that modal languages really are notational variants of (compositional fragments of) certain first-order languages in a very strict sense. I conclude that differentiating between boxes and quantifiers in terms of extensionality is ill motivated from a formal perspective.

You are cordially invited!