The authors offer a theory concerning the nature of a linguistic description, that is, a theoretical statement about the kind of description that a linguist is able to give of a natural language. This theory seeks to integrate the generative conception of phonology and syntax developed by Chomsky and Halle, with the conception of semantics proposed by Katz and Fodor. The authors demonstrate that the integration within one theory of these conceptions of phonology, syntax, and semantics clarifies, further systematizes, and justifies each of them. They also show that such integration sheds considerable light upon the nature of linguistic universals, that is, upon the nature of language. Primary focus is placed on the relation between the syntactic and the semantic components of a linguistic description.