One of the most striking trends in contemporary international law (IL) scholarship is the turn to empirical research methods. Some see this as sign of progress, whereas others call for caution or even show hostility. With a view to the future of IL scholarship, however, all sides in this at times heated debate seem to have considerable problems keeping a clear focus on the key question: What are the implications of this empirical turn in terms of philosophy of legal science, of the social understanding of IL, and, not least, of the place of doctrinal scholarship after the alleged Wende? What is needed, we argue, in order to answer this question is not yet another partisan suggestion, but rather an attempt at making intelligible both the oppositions and the possibilities of synthesis between normative and empirical approaches to law.

Based on our assessment and rational reconstruction of current arguments and positions we outline a taxonomy consisting of the following three basic, ideal-types in terms of the epistemological understanding of the interface of law and empirical studies: toleration, synthesis and replacement. This tripartite model proves useful with a view to teasing out and better articulating implications of and interrelations between positions. As such the model: i) provides a framework to better situate arguments about the role of empirical studies in IL; ii) helps identify real epistemological stakes in order to overcome ‘trench wars’ – or worse: absence of dialogue and genuine argument; and iii) thus ultimately contributes to the development of a genuine basic science-of-law.