As in many other social sciences, in international and comparative education there is an epistemological schism between two main approaches, one of which is traditional whose methodology and methods are historical-hermeneutical, while the other is empirical and oriented towards the natural sciences. In international and comparative education, these two orientations are represented by one scientific community which is devoted to historical approaches--the idiographic orientation, and another community which represents the nomothetic orientation. The epistemological differences between both run too deep to be overcome by normative appeals for mutual understanding and for using all methods available and not only those which are preferred by the respective scientific community. A further problem is that studies on methodology and methods usually look for differences. Instead of causing new dichotomies by looking at differences, in this paper possible common characteristics between both positions will be sought. This will be reached by using a "tertium comparationis." It is based on the "systematicity" of the leading epistemological positions. Systematicity is a philosophical concept developed by Paul Hoyningen-Huene which describes "what makes scientific knowledge special". It will be demonstrated that the main epistemological positions are all systematic. On this basis, a new approach for a joint systematicity is developed, grounded in the generalizability of the research question. This approach may help both of the scientific communities and their respective research to contribute collectively to social problems with their findings, without giving up their specific epistemology.