Abstract
This paper defends the view that the Faculty of Language is compositional, i.e., that
it computes the meaning of complex expressions from the meanings of their immediate
constituents and their structure. I fargue that compositionality and other competing constraints on the way in which the Faculty of Language computes the meanings
of complex expressions should be understood as hypotheses about innate constraints
of the Faculty of Language. I then argue that, unlike compositionality, most of the
currently available non-compositional constraints predict incorrect patterns of early
linguistic development. This supports the view that the Faculty of Language is com-
positional. More generally, this paper presents a way of framing the compositionality
debate (by focusing on its implications for language acquisition) that can lead to its even-
tual resolution, so it will hopefully also interest theorists who disagree with its main
conclusion.