Natural kinds

Abstract

I have tried in this paper to dispose of some of modern essentialism’s newer and more seductive arguments. Putnam’s twin earth tales do not, as he supposes, dispose of Fregean alternatives to essentialist theory. His own account of the extension of natural kind terms is false of nearly all natural kinds and would not yield essentialism even if it were true. Kripke’s theory of the reference of kind terms likewise fails to yield essentialism as a product of the necessary self-identity of natural kinds. The stock candidates for essential properties, moreover, are either not even shared in this world by all things of the kind, or their status is evidently more a feature of our theories than of the world itself. In short, our essentialists’ premises are false, their arguments invalid, and the plausibility of their conclusions specious. Their essences can go back in their Aristotelian bottles, where they belong.