The psychological relevance of transformational grammar: a reply to Stabler.

In a recent reply to our article in Cognition (1984), E. Stabler criticized us on two main points: our construal of transformational grammar (TG) as a “first level” theory; and our claim that a first level construal of TG is crucial, for its psychological relevance. We’d like to dispute both of these points, and in so doing re-emphasize the psychological relevance of modern transformational grammar. First, some basic housekeeping: we must clear up the record by explaining our original position, which, contra Stabler’s interpretation, does not commit us to viewing a grammar as a first level approximation of a parser. Second, we outline Stabler’s reasons for thinking that grammars should be first level theories of this kind. We continue by examining Stabler’s claim that linguists judge their theories by the inherently nonpsychological criterion of relative simplicity. We argue that the psychological notion of learnability is actually the touchstone of comparison. In fact, given this criterion we shall see that one can understand just why linguistic grammars should form the abstract foundation of psychological parsing models.