The theoretical significance of Universal Grammar in second language acquisition
The evidence that native language acquisition is possible only because children are born with an innately-determined language faculty - Universal Grammar - is considerable. The evidence that the same innate ability is involved in second language acquisition (SLA) by older learners is superficially less clear. There are differences both in the context of acquisition and the nature of development. One recent approach suggests that only ‘poverty of the stimulus’ phenomena - where neither the first language (L1) nor the second language (L2) are possible sources for L2 representations - can provide incontrovertible evidence for Universal Grammar (UG) in SLA. I argue that while ‘poverty of the stimulus’ phenomena are important landmarks in theory development in SLA research, they are not the most compelling reason for assuming the involvement of UG. More compelling are attempts to explain L2-L1 differences. The latter are likely to lead to real progress, not only in understanding the nature of SLA but also the structure and organization of the language faculty itself.