In this paper I argue for the necessity of recognizing the epistemological basis of language (and hence of linguistic theory) for research in and theories of second language acquisition. In particular, I review the arguments for a generative approach to linguistic theory (e.g. Chomsky, 1965, 1975, 1981) and for why language as a system of knowledge must be distinct from other sorts of know ledge (Fodor, 1983), with the purpose of clarifying many misconceptions that seem to have arisen with respect to the work in generative grammar over the last 20 years. After doing this I argue that the null hypothesis for second language acquisition is, as concerns its mental representation of linguistic knowledge, that its epistemological status should be assumed to be the same as that of L 1 until proven otherwise. I then demonstrate how SLA theory (e.g. Krashen, 1981) can be elucidated by subsuming (parts of) L2 under linguistic theory with its firm epistemological basis, and how, in particular, one could empirically test Krashen's theory as well as any other theory of SLA that assumes L 1 and L2 to be epistemologically equivalent. In addition I discuss the need for researchers to consider the special epistemological status of linguistic knowledge before prescribing L2 pedagogy. In sum this is a paper that takes a step back into the philosophical debate concerning the mental status of language in general in order for us to be able to take a step forward in second language research in particular.
Linguistic Theory in Second Language Acquisition by Suzanne Flynn and Wayne O'Neil