ABSTRACT
Putnam argued that underlying features of referents determine reference for natural kind terms. Many philosophers quickly agreed. Nearly fifty years later, this externalism about natural kind terms is the dominant view. Superficial kind terms developed their natural kind senses owing to metaphysically contingent facts about the world. This chapter provides an account, suggesting that natural kind terms have the semantics Putnam says they do because the concepts develop in a way that conforms to our demand for simple, powerful explanations and natural kind terms label kinds that are important even if their referents have nothing deep in common. It explains why natural kind terms have the semantics that they do without making a similar presupposition.
