In his book The Quest for Knowledge in International Relations, Richard Ned Lebow addresses foundational questions about the academic enterprise of international relations (IR). What counts as knowledge in the discipline? By which methods and approaches can it be pursued? And on which grounds can knowledge claims be made? These overarching questions structure Lebow's survey, while the topics of individual chapters are approached from the divide between positivism and interpretivism.

According to Lebow, positivism and interpretivism and their different approaches to acquiring knowledge constitute “a core cleavage among IR theorists” (14), a division that also supersedes and cuts across IR paradigms. Lebow defines positivism as “the search for scientific theories or rationalist models that aim to explain and predict,” (38) with King, Keohane, and Verba's Designing Social Inquiry as the most influential (and notorious) book in this tradition (143). Interpretivism, on the other hand, is defined as the “antithesis” to positivism, with a wide and diverse range of intellectual influences. What this perspective boils down to, according to Lebow, is the emphasis on intersubjective understandings and the notion that the social world cannot be studied in the same way as the physical world because cultural and h