Blau, Peter

Peter M. Blau (1918–2002) was a twentieth-century, Austrian-born, American social theorist who contributed [Page 55]widely to sociology in the areas of organizational theory, exchange theory, social mobility, stratification, and macrostructural theory. Committed to a nomothetic approach to social science, Blau developed insightful and creative theory, which he rigorously tested through the innovative use of previously underutilized data sources. His empirical work often revealed new insights inspiring modifications to his original theories; this explains the broad scope of Blau's work. The publication of The American Occupational Structure (1967), with Otis Dudley Duncan, demonstrated the effectiveness of linear regression and path analysis, thus popularizing those techniques now considered indispensable for statistical analysis in sociology. Two themes that run through Blau's research are the interrelationship between the individual and society, the micro-macro link, and an interest in stratification and equality. In his early work on bureaucracy, exchange, and status attainment, Blau focused on the effect of the individual on macrostructures. Later work focused on the constraints imposed on individuals by society, culminating in a deductive macrostructural theory that conceptualizes social structure as a multidimensional space of social positions characterized by group affiliation, known as “Blau-space,” which demonstrates how population structures constrain the choices of individuals and affects their chances for intergroup affiliation, intermarriage, and status attainment.

Blau received his bachelor's degree in sociology from Elmhurst College and his doctorate in 1952 from Columbia University, working with Robert K. Merton. His dissertation was a field study of officials in a federal law enforcement agency modeled on the design of Roethlisberger and Dickson's work on the Western Electric Company. Contrary to the prediction of Weber that the bureaucratization and rationalization of modern life constrained individual freedom, Blau found that officials often circumvented bureaucratic prescriptions and discovered creative informal ways to deal with their cases. The most well-known illustration of this was that agency officials who were officially prohibited from discussing cases with anyone but their supervisors used their lunch hours to discuss cases and exchange advice. This observation became the cornerstone of Blau's exchange theory. Despite the identification of social mechanisms that allowed bureaucrats to create an alternative to proscribed channels, Blau's focus on only one case precluded his ability to generalize or to make any claims about the attributes of bureaucracy characterized by Weber: growth, division of labor, hierarchy, and impersonal automated decision making.

In “A Formal Theory of Differentiation in Organizations” (1970), Blau presented a theory, based on data from 53 state employment security agencies, that explains why the rate of differentiation in organizations declines for large organizations. He found that although differentiation increases in large organizations, it does so at a reduced rate.

The reason: Differentiation creates a need for additional administrative overhead, which undercuts the advantage of the economy of scale provided by a large organization. Reducing differentiation reduces organizational complexity, which eliminates the need for additional administrative costs. Data from other organizations collected over the years have confirmed these relationships.

In 1964, while at the Center for the Study of Behavior Science at Stanford University, Blau turned his attention to exchange theory. At that time, recent work by George Homans and Richard Emerson on exchange relations made exchange a popular topic. Blau's observation about the exchange of advice for deference among officials in the law enforcement agency forced him to think about the relations between the specific personal microlevel exchanges and general exchange patterns inherent in society. In Exchange and Power in Social Life (1964), Blau argued that the person-to-institution and institution-and-institution relationships in society are emergent properties of exchange patterns at the microlevel. Blau's work differed from that of Homans's and Emerson's in that his interest in the individual was secondary; his goal was not to develop a microtheory about exchange and status among individuals, but to focus on the sociological level of the institution.

...