Why have some lines of inquiry in international studies exhibited consensus in their results, while others have not? Fred Chernoff hypothesizes that the use of divergent criteria of explanation may account for differing levels of consensus: if scholars researching some phenomenon do not operate with the same standards for what constitutes a good—or a better—explanation, it may be more difficult for those scholars to agree on which of several competing explanations is the best. To evaluate this hypothesis, Chernoff canvasses scholarly work on nuclear proliferation, alliance formation, and the democratic peace, recording the explanatory criteria used in the most influential work in each line of inquiry to determine whether disagreements about criteria of explanation and a lack of consensus findings go together and whether agreements about criteria and consensus findings go together. He concludes that these associations hold and that this helps explain why democratic peace research has achieved a general consensus “with regard to the power of the liberal explanation for the behavior of democratic dyads” (p. 233), while research on the other two topics has not achieved such consensus.

Chernoff makes a powerful case for the importance of “metatheory” in conducting and evaluating social scientific research. Without clarity abo