One of the most outstanding intellectual achievements in the history of classical thought in social sciences which have remained influential up until today are undoubtedly associated with the name of Max Weber. Through a detailed text analysis and a conceptual mapping of the logic of the argumentation, this paper sets out to offer a profound insight into the classical German sociologist’s approach to science, both “early” (about 1903/4) and “late” (post-1913), in terms of some fundamental matters of epistemology and methodology. The first part of this paper investigates social economics in terms of its theoretical and methodological foundations and applicability, while the second part looks at interpretive sociology from the same perspectives, with an emphasis on the differences between the two approaches. We argue that Weber’s dualist methodological attitude became explicit and dominant in his later writings. In addition, as he brought in focus the theory of social action, he not only became an explicit proponent of methodological individualism, but he also revisited and specified the logic and role of “causal explanation” and “interpretation”. Interpretive sociology no longer seeks a causal explanation for individual historical events by applying nomological knowledge, but instead commits itself to finding “causally adequate” explanation for the course and consequences of different types of social actions. Interpretation, in turn, no longer means an analysis of effects concerning the cultural significance of individual historical events in a special sense, but an interpretive understanding of various types of social actions, rational or “irrational”, directly or in a motivation-like manner. The paper concludes with a summary designed to highlight key legacies of Weber’s oeuvre that have remained valid and valuable for any analytical and empirical research in sociology.