E-language, I-language and the Order of Parameter Setting

1 The problem: learnability of underlying structure All the various grammatical characteristics of adult grammar will eventually appear in child language. They will do so successively, and reveal a learnability hierarchy that holds for all primary learners of the language. As a matter of fact Brown (1973:313ff) showed how 13 grammatical morphemes of English obey such an order of appearance. What we value in Brown is his attention to the order of learning step and his attempt to derive that order from the interaction of system factors and input factors. The first grammatical characteristics in child language are not arbitrary choices. They remind one of a Greenberg-like language typology. An explanatory relation between language typology, child language and universal grammar was brought to the fore in Jakobson (1942) for phonological features and, as he pointed out, the same relationship is likely to appear in syntax as well. Chomsky (1981) has proposed that primary language acquisition might be seen as a stepwise procedure that sets yes/no parameters in an a priori frame. This tallies well with Jakobson’s conception of language acquisition. The parameters of grammar are set according to a kind of learnability hierarchy. The setting of some typological parameters should be understood as a precondition for the setting of other more language specific parameters. Since child language acquisition is responsive to the typological features of the target language, it must be successful in picking up evidence from the input. However, there is a paradox here. The right selection of evidence must often abstract away from other construction specific and language specific features. For example, a so-called V-second language like Dutch moves all finite verbs into an operator position <+C>, where <+C> is defined as the first position c-commanding the predication IP/VP on the righthand side. The X <+C> head marks a prospective operator head and Spec,C a prospective operator phrase, as in (1). The V-second rearrangement of the finite verb V<+fin/+C> takes place only in root sentences and not in subordinates. Yet, as we will show in detail, practically all sentences addressed to the child are root sentences and these invariably have the finite verb in the <+C> position.