This paper, part of a multi–author project evaluating the evolution of theoretical paradigms in international relations (IR), evaluates the Liberal paradigm form a Lakatosian perspective. There is a distinct "Liberal" Scientific Research Program (SRP) in the study of international relations, based on three core assumptions. These Assumptions are shared by Ideational, Commercial and Republican variants of Liberal theory. The Liberal SRP is clearly progressive in the Lakatosian sense, that is, it explains a broad and expanding domain of empirical phenomena more accurately than competing research programs – and does so in such a way as to meet the specific Lakatosian criteria of "heuristic", "temporal" and "background theory" novelty. Liberal theory is thus among the most promising, perhaps the most fruitful and promising, of contemporary paradigms in IR theory. Yet legitimate doubts can be raised about the utility of Lakatosian theory as a means to evaluate research in IR. In particular, one might question its view that theories from competing paradigms are mutually excusive, which encourages one–on–one testing of unicausal theories, rather than estimation of the proper (and sometimes overlapping) scope of paradigms, or the construction of multi–paradigmatic syntheses. Given the current stage of IR theory, these two tasks may offer greater explanatory insight into world politics than unicausal theory testing. This conclusion does not undermine, however, the positive assessment of Liberal theory, which both supports clear empirical scope conditions and can play a foundational role in fruitful multi-theory syntheses.
Moravcsik, Andrew. "Liberal International Relations Theory: A Social Scientific Assessment." Working Paper 01–02, Weatherhead Center for International Affairs, Harvard University, April 2001.