Functional Differentiation and the Public Sphere: An Attempt in Theoretical Formalization for Historical and Comparative Research

This study elaborates on the concept of functional differentiation as a structural feature of modern society. Methodological criteria to judge whether society is differentiated functionally remain elusive, although these must be presupposed when the concept of functional differentiation is applied to the comparison of societies. Certainly, a society is not functionally differentiated if judicial decision, for example, is always dependent on external conditions, whether power or wealth of parties, and hence, the legal system cannot operate according to its own logic. Conversely, however, the autonomy and independence of a functional system never imply the functional differentiation of society as a whole because the case where other functional logics can be violated directly by political or monetary power is not completely excluded. The existence of some functional institutions, for example, the parliament, bureaucracy, courthouse, market, and educational system, does not guarantee a functionally differentiated structure. To exploit this concept for a comparative survey, the inquiry must focus not only on differentiation itself but also on preconditions leading to such a structural change and the formalization of this relationship in general terms. This study underlines one of the formal features of functional differentiation, namely, the idea of horizontal heterogeneity, the emergence of which assumes the societal spread of the tolerance for diversity and rejection of the omnipotent instance that orders the world hierarchically. In addition, the public sphere in Western modernization is highlighted as one of the significant places where these collective mentalities and expectations were cultivated. On the basis of this theoretical consideration, previous historical and sociological studies on East Asian civilization processes, especially the Japanese case, are revisited.