The Logic of Conceivability

Hyperintensionality: proof-theory and semantics



Hyperintensionality Afternoon

Please find some pictures of the Hyperintensionality afternoon with Prof. Greg Restall and Dr. Mark Jago here.


On Tuesday March 7th, the LoC will host two scholars giving talks on hyperintensionality: Professor Dr. Greg Restall (University of Melbourne) and Dr. Mark Jago (University of Nottingham).

Location: ILLC Seminar Room, F1.15

Date and Time: Tuesday March 7th, 14.15 - 17.30.




14.15 - 15.45

Speaker: Prof. Greg Restall

Title: Proof Identity, Invariants and Hyperintentionality



This talk is a comparison of how different approaches to hyperintensionality, aboutness and subject matter treat (classically) logically equivalent statements. I compare and contrast two different notions of subject matter that might be thought to be representational or truth first — the of subject matter introduced in Stephen Yablo’s Aboutness (Princeton University Press, 2014), truthmakers conceived of as situations, as elaborated in my “Truthmakers, Entailment and Necessity”  (AJP, 1996), and I contrast this with the kind of inferentialist account of hyperintensionality arising out of the proof invariants I have explored in recent work. 


15.45 - 16.00 Coffee break


16.00 - 17.30

Speaker: Dr. Mark Jago

Title: Meaning: between truth and proof



Meaning can’t be understood purely in proof-theoretic terms, but neither can it be understood without appeal to proof-theoretic structure. That’s the claim I’ll defend in the first half of this talk. In the rest of the talk, I’ll sketch an approach to meaning that overcomes this dilemma. On this approach, the content of a sentence is understood in terms of the situations according to which it takes a truth-value, as on the realist, truth-functional account of meaning. But those situations cannot all be possible worlds, on pain conflating distinct meanings. Meaning is hyperintensional, and so the situations in question must be drawn from impossible as well as possible worlds. Those worlds must bear logical relations to one another, on pain of trivialising our theory of meaning. I suggest that worlds are linked to one another in graph-like structures, which structurally resemble proof trees. This approach, I argue, resolves some of the problems of hyperintensional meanings.