27 August 2013, Logic Tea, Kasper Christensen

Abstract

Etchemendy's claim, that Tarski's definition of logical consequence cannot serve as an analysis, rests on two essential tenets of Tarskis definition: (i) the definition is interpretational in character; two non-isomorphic models differ in the meaning assigned to at least one of the non-logical terms of the language, and (ii) Tarski's definition is reductive: each model represents actual truth.

To add weight to his claim, Etchemendy asks us to consider Kripke Semantics and claims that we cannot view this in line with Tarski's definition. Instead, Kripke Semantics must be viewed as a representational semantics where each model represents a certain way that the world could have been.

I will suggest that the best way to understand Kripke Semantics does not involve a rejection of (i) and (ii) -- although it does involve a modification of (ii).

The picture of Kripke Semantics that emerges presents us with a clear cut way to answer an attack on Kripke Semantics lead on by Hintikka and Cocchiarella, to the effect that Kripke Semantics illegitimately excludes some possibilities when the modal box is understood as logical necessity.

For more information, please contact Johannes Marti (johannes.marti at gmail.com), Sebastian Speitel (sebastian.speitel at gmail.com), or Matthijs Westera (M.Westera at uva.nl).