ABSTRACT
… it seems to me that, if anything far-reaching and real is to be discovered about the actual grammar of the child, then rather devious kinds of observations of his performance, his abilities, and his comprehension will have to be obtained, so that a variety of evidence may be brought to bear on the attempt to determine what is in fact his underlying linguistic competence at each stage of development. Direct description of the child’s actual verbal output is no more likely to provide an account of the real underlying competence in the case of child language than in the case of adult language …Not that one shouldn’t start here, perhaps, but surely one shouldn’t end here. … (Chomsky, 1964, p. 36)
