Causal mechanism and explanation in social science

In the social sciences, the development of a specific social event or structure is often explained by a statistical correlation between an independent variable and a variable assumed to be dependent upon it. This mode of explanation is contested by a methodology of causal reconstruction that operates with the concept of mechanisms. A mechanism is a process in which a set of linked steps leads from initial conditions to an outcome or effect. Mechanisms are general concepts, subjecting individual cases to a general category. Except for the literature dealing specifically with the concept, the term 'mechanism' is often used without definition of its substantive content; there is no agreement with respect to the unique or plural character of the initial conditions, nor to the structure of the causal path leading to a specific outcome. Nevertheless, mechanisms have played a crucial role in detailed causal analysis of complex historical events, such as the financial crisis of 2008 and German unification of 1989.