A minimal class of cybernetic models needed in making the transition from a description of control systems to a description of social systems is discussed. Several applications are considered in connection with studies of learning and creativity in individuals and small groups. Possible extrapolations of these to social systems are suggested. Bases for the need of an elaborate structure are given. A class of models is proposed that consists of a pair of logically distinct and differently identified components. One component represents a hierarchically organized set of linguistic constraints on discourse, and the other represents a hierarchic structure of mechanisms. A concept such as homeostasis can be applied to it that enables analogies to be made between elements in one component and subsets of elements in the other component. Thus, discourse can affect the development of a mechanism, and the mechanism can affect discourse. A composite model of this kind appears suited to developmental systems of psychology. (Author)