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Universal Grammar and Second Language Acquisition Theory

Second language acquisition (SLA) is characterized by extreme interlearner variation in rate of acquisition, styles and strategies of learning, motivation and goals, and eventual success. It is a daunting task to adduce principles that would make all this disorder seem orderly. Fortunately, there are limits to the apparent chaos. SLA is not infinitely variable; certain kinds of deviant sentences are not produced or fossilized, certain infelicitous hypotheses are not entertained. This suggests that the problem of finding order may not be intractable after all. However, we may have to make our goals somewhat more modest. We should perhaps be content to look for common denominators—features of SLA shared by all learners. We should try, in other words, to discover the mechanisms that constrain the chaos. Such thinking is at the heart of investigations of the possibility that the source of constraints on SLA is the same as the source that many believe constrains first language acquisition (FLA). The most conspicuous theoretical orientation to this possibility is derived from Chomsky's theory of Universal Grammar (UG), which attempts to identify those elements that are common to all natural languages and to spell out the nature and the form of grammatical constraints. According to UG theory (e.g., Chomsky, 1981), the human mind is in possession of grammars characterized by inviolable principles.