Axiomathes

, Volume 21, Issue 4, pp 553–579

Models for Counterparts

Authors

Original Paper

DOI: 10.1007/s10516-010-9120-1

Cite this article as:
Torza, A. Axiomathes (2011) 21: 553. doi:10.1007/s10516-010-9120-1

Abstract

Lewis proposed to test the validity of a modal thesis by checking whether its possible-world translation is a theorem of counterpart theory. However, that criterion fails to validate many standard modal laws, thus raising doubts about the logical adequacy of the Lewisian framework. The present paper considers systems of counterpart theory of increasing strength and shows how each can be motivated by exhibiting a suitable intended model. In particular, perfect counterpart theory validates all the desired modal laws and therefore provides a way out of the logical objection. Finally, a weakening of perfect counterpart theory is put forward as a response to some metaphysical objections.

Keywords

Counterpart theory Modal logic Identity Intended model

Copyright information

© Springer Science+Business Media B.V. 2010