ABSTRACT
Bridge hypotheses or bridge assumptions connect the macro-level of social structures with the micro-level of the subjective views of the actors and their actions. Bridge hypotheses formulate the result of what Karl R. Popper called "institutional analysis" in his concept of situational logic. The formulation of bridge hypotheses is one of the most important and difficult tasks for sociology. Bridge hypotheses are a necessary, although not sufficient, part of the fundamental elements of a sociological explanation. The solutions to the two problems of incompleteness and meaninglessness are closely related. They both depend on the "correct" and adequately refined formulation of bridge hypotheses. The bridge hypotheses translate the concrete, specific concepts from the structural level into the general, theoretical concepts of the abstract action theory, and—at the same time—empirically interpret the action theory. The independent variables of the action theory are the dependent variables of the bridge hypotheses.
