Month: October 2023

Talk of interest on 10/27: Dorr and Mandelkern

Logic Colloquium talk this week

Cian Dorr and Matthew Mandelkern (NYU Philosophy)

“The Logic of Sequences”

Friday, October 27, 2:00pm – 3:30pm

hybrid: ROWE 320 and Zoom (link below)



In the course of proving a tenability result about the probabilities of conditionals, van Fraassen (1976) introduced a semantics for conditionals based on sequences of worlds, representing a particularly simple special case of ordering semantics for conditionals. According to sequence semantics, ‘If p, then q’ is true at a sequence just in case either q is true at the first truncation of the sequence where p is true, or there is no truncation where p is true. This approach has become increasingly popular in recent years. However, its logic has never been explored. We axiomatize the logic of sequence semantics, showing that it is the result of adding two new axioms to Stalnaker’s logic C2: one which is prima facie attractive, and one which is complex and difficult to assess.  We also show that when sequence models are generalized to allow transfinite sequences, the result is the logic that adds only the first (more attractive) axiom to C2.



Talk of interest on 10/25: M. Kaufmann

The Philosophy Brownbag on Wednesday, October 25, at12:15pm will feature our own Magdalena Kaufmann with a talk titled Conjunctions (in)forming Conditionals. The meeting is hybrid, in-person in the basement lounge of Manchester Hall and online via Zoom. Contact Stefan Kaufmann for login information.

Abstract: In many natural languages (including English), sentential conjunctions instantiating the schema `p and q’ can receive conditional interpretations similar to `if p, then q’ (“conditional conjunctions”). Empirical evidence from several languages suggests that this interpretation comes about when the first sentential conjunct is marked or interpreted as a topic. While this allows for a compositional interpretation of the phenomenon, it does not in itself explain puzzling restrictions on the kinds of conditional meanings that can be expressed by conjunctions: conditional conjunctions cannot normally be used to express generalizations and to make predictions about future sequences of events (roughly, generic and causal-like/metaphysical conditionals), but not to express epistemic conditionals (roughly, reasoning under uncertainty about current and past states of affairs). Special discourse settings can, however, overwrite this restriction and make conditional conjunctions felicitous as epistemic conditionals.