Consequence theoretic semantics and entailment

David Ripley (Monash University)

Dave Ripley (Monash) will present "Consequence theoretic semantics and entailment" at 11 in Old Arts 152 on 1 March.

Abstract: The purpose of this talk is to present and begin to articulate an alternative to both model-theoretic and proof-theoretic semantics: consequence-theoretic semantics. On this approach, both proofs and models are mere technical auxiliaries, without any direct connection to meaning. Meaning is rather located in the consequence relation itself. The key theoretical notion I will use, borrowing from Greg Restall, is that of a position---a collection of assertions and denials. Some positions are ruled out, and others are not.

On this basis, a consequence-theoretic semantics, like any semantics, owes (among other things) an account of entailment. But while consequence is a matter of ruling out, entailment seems to be a matter of guaranteeing or ruling in; it's not immediately obvious how to use a position-theoretic framework to understand entailment. This talk shows how to do it, by developing a notion of equivalence between positions, and using this to understand when assertions and denials can be implicit in a position. Seen this way, entailment and consequence might have the same extension, or they might not; it depends on what structural features consequence itself has. I'll show a few examples of this dependence.