A familiar story about mid-twentieth-century American psychology tells of the replacement of behaviorism by cognitive science. Between these two, however, lay a borderland, muddy and much trespassed-upon. This paper relocates the origins of the Chomskyan program in linguistics there. Following his introduction of transformational generative grammar, Chomsky (b. 1928) mounted a highly publicized attack on behaviorist psychology. Yet when he first developed that approach to grammar, he was a defender of behaviorism. His anti-behaviorism emerged only in the course of what became a systematic repudiation of the work of the Cornell linguist C. F. Hockett (1916–2000). In the name of the positivist Unity-of-Science movement, Hockett had synthesize...