 One apparent corollary of this is significant for those many philosophers of language who have agonized over how to construct a theory of meaning for English. A common thought is that such a theory ought to take the form of a statement of the referential properties of the expressions of English—a link between words and objects in the world—from which the truth conditions of all English sentences can be derived (e.g., Davidson 1970, Montague 1970; see the entries for  theories of meaning  and  reference).  Echoing P.F. Strawson (1950), Chomsky suggests that referring is something people do. They use words in doing so, it is true, but referring is not something that words somehow do by themselves, through some fantastical medium, English (2000: 40–1). If referential properties of expressions amount to anything, rather than being relational properties between expressions and external objects (or “word-world” relations) they should be thought of as embodying instructions to the individual’s conceptual system, one of the performance systems with which the language faculty interfaces (an idea explored in Jackendoff 2002). If Chomsky is right, a great deal of the philosophy of language is either radically off beam or needs considerable re-interpretation (see Hornstein 1989, Ludlow 2003, Pietroski 2003, Stainton 2006).