ABSTRACT
For a number of years, researchers on language behavior have believed that it involves the interaction of different kinds of partially autonomous systems of general and specific knowledge. That is, language is a modality, a natural kind of mental organization. The differentiation of such modalities as language, vision, taste, is pre-theoretically satisfying, but requires scientific explanation. How is it that they coalesce and emerge? How does the child know that aspects of his or her early experience are interrelated together and which motor patterns are related to them?
