Language is the most fundamental institution of human society. It sets us apart from all other species, and our other institutions would be impossible without it. However, to call language an “institution” is already to take sides in a debate about what language is, one which implicates the agent–structure problem. In recent years the dominant view in linguistics has been to think of language as being in the heads of individuals, whether as a “mental organ,” “computational device,” or even “instinct.” On this view linguistics is essentially a branch of cognitive science. A very different view is taken by those who emphasize the supra-individual character of language. Saussure, Wittgenstein, Davidson, and Searle – to drop just a few names – have all highlighted the ways in which our use of language is constituted and regulated by norms shared by a community of speakers. From this perspective language is less a cognitive than institutional fact. Of course, institutions cannot exist apart from people, so “top-downers” would agree that what is in people's heads matters too, just as “bottom-uppers” would agree that language must be shared for communication to be possible. But, as in the agent–structure problem more generally, it is not obvious how to combine parts and whole.

Importantly, the interdependence between speakers and language communities means that an implicit subjective–objective polarity structures both perspectives. For social scientists the most familiar example of this polarity is probably Saussure's distinction between langue and parole, the former refer- ring to the structure of a language considered as an abstract system of signs, the latter to actual speech. As an institutionalist Saussure neglects speech, whereas as a cognitivist Chomsky neglects institutions, but his distinction between “competence” and “performance” reflects the same polarity. A speaker is competent if she can use a language's generative grammar (a kind of “langue in the head”) to communicate, while her performances actualize this potential in speech.