The concepts of rationality have always been and, we can assume, will always remain controversial in the social sciences in general and in sociology in particular. Schütz made an important contribution to this discussion in the context of the Schumpeter -Parsons Seminar at Harvard University in 1940. In this paper, he criticized any confounding of the levels of everyday life and scientific reasoning and elaborated the position that would come to form the basis of his phenomenologically based hermeneutical approach to the social sciences.