Arguing about innateness

This paper lays out the components of a language acquisition model, the interconnections among the components, and the differing stances of nativism and empiricism about syntax. After demonstrating that parsimony cannot decide between the two stances, the paper analyzes nine examples of evidence that have been used to argue for or against nativism, concluding that most pieces of evidence are either irrelevant or suggest that language is special but need not invoke innate ideas. Two pieces of evidence - the development of home sign languages and the acquisition of Determiners - do show not just that language is special but that the child has innate syntactic content. The existential claim that nativism makes - there is at least one innate syntactic idea - is an easier claim to verify than the universal claim that empiricism makes - there are no innate syntactic ideas.