 A major theme across many varieties of Edo-period Confucianism was a focus on language. As mentioned above in the discussion of the fundamental ideas of Confucian philosophy, a basic assumption is that an understanding of a term for a human relation entails a recognition of how that relation should be enacted. To know fully what the term friend means, for example, is to know how a friend ought to act. That is the principle of the trueing up of terms, or the rectification of names. Previous to the Edo period in Japan that was about as far as the analysis went. With the expanded range of issues addressed in the new forms of Confucianism, however, the question was whether that same principle could be applied beyond the five binary human relations. For example, do the essential meanings of terms like human nature, mind, harmony, principle, or learning also entail normative behaviors? Can a philosophy of education, for example, be generated out of a close analysis of the meaning of the ancient word for “learning” (gaku) in the classic Chinese texts? To what extent do words have individual meanings and to what extent is there a core of terms that are in internal relation to each other that can be understood only together? And so forth. Such themes became the center of attention in the Confucian academies and they raised questions about the nature of language and how to study it.