Book review of Wolfgang Weidlich's Sociodynamics: A Systematic Approach to Mathematical Modelling in the Social Sciences

Abstract

This volume represents a magnum opus by Wolfgang Weidlich, summarizing his long work in the area of sociodynamics. It lays out the origins and development of his ideas on this topic, presents a variety of applications drawn from his previous work, and offers some new insights and suggestions. For those acquainted with Professor Weidlich’s work, it is a satisfying summing-up. For those unacquainted with it, the book provides a good overview and discussion of what is involved in it, both its weaknesses and its strengths. It has a definite predecessor,Weidlich’s 1983 book with his frequent coauthor, Gunter Haag, Concepts and Models of a Quantitative Sociology, but the book we are discussing here goes well beyond the arguments and models presented in that volume. The book contains three parts and twelve chapters. The first part, with three chapters, discusses general background issues. The first chapter provides the philosophical and historical origins, particularly from general systems theory and synergetics. Weidlich’s long association with the founder of synergetics, Haken [2], is discussed, with synergetics being seen as an extension of general systems theory (both of them were associated with the Institute for Theoretical Physics at the University of Stuttgart for many years). In turn, sociodynamics is seen as an extension of synergetics into the social sciences realm. The second chapter rather briefly discusses some criticisms of quantitativemodeling of the sociodynamics sort, including the especially “physicalist” critique, the argument that such models merely transfer physics ideas mindlessly into social sciences. Unfortunately, this chapter does not deal with some of the more substantive criticisms of sociodynamics to be discussed below. The third chapter presents the standard mathematics of the sociodynamics models of Weidlich. This ultimately involves a particular example deriving a master equation that describes the evolution of probability distributions. Particularly important is the evolution of the mean-value equations that can depict expected outcomes over time. These equations operate in a stochastic framework, which is supposed to represent the actions of the individuals or other lower-level units in the system. Following synergetics, trends in order parameters usually determine the overall outcomes. Also like synergetics, nonlinear interrelationships are assumed that allow for discrete phase transitions, a deep theme of sociodynamics and one of its more appealing aspects. Much of the emphasis is on these