Abstract

Alik Pelman proposes a sceptical challenge to the widely accepted thesis that theoretical identities are necessary. His argument relies on the possibility of the manifest criterion of identity. In this article, we argue that given the necessity of the obtaining of the identity criterion, Pelman’s sceptical argument against the necessity of theoretical identities cannot be effective. By comparing Pelman’s sceptical argument with classical sceptical arguments, it is demonstrated that there is a sense in which classical arguments are effective but not Pelman’s.