In today's social and behavioral sciences, the complexity of many problems requires the development of a number of highly specialized disciplines. However, the cost of such development is the obscuring of the relationships between these disciplines. This dilemma calls for a "mixed strategy" that combines the advantages of specialization with those of a unified viewpoint. The purpose of this book is to provide the connective tissue that is needed to obtain an overall view. The principles of general system theory naturally lead to a framework that includes many known models and content areas; our intention is to strike a balance between generality and plain usefulness. The first part of this book introduces a social system as a network of inter­ acting decision makers. This general framework allows a classification of a num­ ber of more specific structures, which include autocratic and democratic systems, systems with collective and individual decision making, and systems with and without coalitions. In the second part, various psychological schools are seen as specific instances of a general paradigm, which is consequently a point of departure for a taxon­ omy of learning systems. For a full understanding of this matter, we recommend a careful study of the first four chapters as an introduction to the concepts elaborated in the second part of the book. ix PREFACE x Though the subject matter has a formal background, it does not require a mathematical knowledge in depth; familiarity with elementary probability theory and linear algebra is enough.