[A]n entire community of highly trained professionals, bringing to bear years of conscious attention and sharing of information, has been unable to duplicate the feat that every normal child accomplishes by the age of ten or so, unconsciously and unaided . (Jackendoff 1994: 26)
Large-scale sensory deficit seems to have limited effect on language acquisition. Blind children acquire language as the sighted do, even color terms and words for visual experience like “see” and “look.” There are people who have achieved close to normal linguistic competence with no sensory input beyond that can be gained by placing one’s hand on another person’s face and throat. The analytic mechanism of the language faculty seem to be triggered in much the same way whether the input is auditory, visual, even tactual, and seem to be localized in the same brain areas , somewhat surprisingly.
These examples of impoverished input indicate the richness of innate endowment — though normal language acquisition is remarkable enough, as even lexical access shows, not only because of its rapidity and the intricacy of result. Thus very young children can determine the meaning of a nonsense word from syntactic information in a sentence far more complex that they can produce.
A plausible assumption today is that the principles of language are fixed and innate , and that variations is restricted in the manner indicated. Each language, then, is (virtually) determined by a choice of values for lexical parameters: with the array of choices, we should be able to deduce Hungarian; with another, Yoruba. … The conditions of language acquisition make it plain that the process must be largely inner-directed, as in other aspects of growth, which means that all languages must be close to identical, largely fixed by initial state . (Chomsky 2000. New Horizons … : 121-2)
Greenberg's reputation rests in part on his contributions to synchronic linguistics and the quest to identify linguistic universals . In the late 1950s, Greenberg began to examine corpora of languages covering a wide geographic and genetic distribution. He located a number of interesting potential universals as well as many strong cross-linguistic tendencies.
In particular, Greenberg invented the notion of "implicational universal" , which takes the form, "if a language has structure X, then it must also have structure Y." For example, X might be "mid front rounded vowels" and Y "high front rounded vowels" (for terminology see phonetics ). This kind of research was taken up by many scholars following Greenberg's example and remains important in synchronic linguistics.
Like Noam Chomsky , Greenberg sought to discover the universal structures underlying human language. Unlike Chomsky, Greenberg’s approach was empirical rather than logico-deductive. Greenberg’s approach, often characterized as " functionalist ", is commonly opposed to Chomsky’s rationalist approach. An argument to reconcile the Greenbergian and Chomskyan approaches can be found in Linguistic Universals , edited by Ricardo Mairal and Juana Gil (2006).
Many who are strongly opposed to Greenberg's methods of language classification (see below) nevertheless acknowledge the importance of his typological work. In 1963 he published an article that was extremely influential in the field: "Some universals of grammar with particular reference to the order of meaningful elements" .
“ An I-language approach [ i.e. a Chomskyan approach … ] sees language acquisition as a logical problem that can be solved in principle without looking at the development of actual children in detail. ”