Proof Identity, Invariants and Hyperintensionality

March 7, 2017

Abstract: 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 – Aboutness (Princeton University Press, 2014), and truthmakers conceived of as situations, as discussed in my “Truthmakers, Entailment and Necessity.” I contrast this with the kind of inferentialist account of hyperintensionality arising out of the proof invariants I have explored in recent work.

This is a talk presented at the Hyperintensionality Afternoon, held by Francesco Berto’s project on the Logic of Conceivability.


I’m Greg Restall, and this is my personal website. I am the Shelby Cullom Davis Professor of Philosophy at the University of St Andrews, and the Director of the Arché Philosophical Research Centre for Logic, Language, Metaphysics and Epistemology I like thinking about – and helping other people think about – logic and philosophy and the many different ways they can inform each other.


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