Habermas introduces the concept of “reconstructive science” with a double purpose: to place the “general theory of society” between philosophy and social science and reestablish the rift between the “great theorization” and the “empirical research”. The model of “rational reconstructions” represents the main thread of the surveys about the “structures” of the life-world (“culture”, “society” and “personality”) and their respective “functions” (cultural reproductions, social integrations and socialization). For this propose, the dialectics between “symbolic representation” of “the structures subordinated to all worlds of life” (“internal relationships”) and the “material reproduction” of the social systems in their complex (“external relationships” between social systems and environment) has to be considered. This model finds an application, above all, in the “theory of the social evolution”, starting from the reconstruction of the necessary conditions for a phylogeny of the socio-cultural-life forms (the “hominization”) until an analysis of the development of “social formations”, which Habermas subdivides into primitive, traditional, modern and contemporary formations.
This paper is an attempt, primarily, to formalize the model of “reconstruction of the logic of development” of “social formations” summed up by Habermas through the differentiation between vital world and social systems (and, within them, through the “rationalization of the life-world” and the “growth in complexity of the social systems”). Secondly, it tries to offer some methodological clarifications about the “explanation of the dynamics” of “historical processes” and, in particular, about the “theoretical meaning” of the evolutional theory’s propositions. Even if the German sociologist considers that the “ex-post rational reconstructions” and “the models system/environment” cannot have a complete “historiographical application”, these certainly act as a general premise in the argumentative structure of the “historical explanation”.