Langford and Ramachandran on Occasional Identities

Abstract

In their ‘Rigidity, Occasional Identity and Leibniz’ Law’, The Philosophical Quarterly, 50 (2000), pp. 518–26, Steven Langford and Murali Ramachandran argue that my defence of the transiency and contingency of identity given in my Occasions of Identity is flawed. In that work I supported what I called the Occasional Identity Thesis by defending certain theses about rigid designation and time-indexed properties. Langford and Ramachandran argue that the theses in question have unacceptable consequences. I attempt to show that their argument fails, and that their alternative proposal concerning Leibniz' Law does not work.