Abstract

There is a form of argument for a certain kind of essentialist conclusion which appears not to depend upon any appeal to intuition. Identity statements involving natural kind terms are often adverted to in the literature as examples of the necessary a posteriori, and it can appear as though the essentialist is on very strong ground with respect to these claims. It is not merely that they are apt to strike one as plausible in the light of philosophical arguments or modal intuitions; rather, they appear to be provable, given only fairly trivial logical principles and uncontroversial scientific truths. This paper attempts to counter the claim, made particularly convincing by the work of Saul Kripke, that this indeed the case.