Comparing new theory with prior beliefs: market civilization and the democratic peace

Abstract

Stuart Bremer counseled against the falsificatiÖnişt convention of testing new models against the null hypothesis of no model. Instead, new models should be compared against prior beliefs, and theories should compete, whenever possible, on afield of equivalent test conditions. This article applies Stuart Bremer's notion of comparative theory testing by comparing a new model of contract norms with the prior institutionalist model of democratic peace. On afield of equivalent test conditions it is found that the hypothesis for contract norms (that the democratic peace is contingent upon economic development) is thousands of times more likely to be true than the hypothesis for institutionalist theory (that democracy pacifies all dyads regardless of economic conditions). Democracy appears to be a significant force for peace only in dyads that are above the median income: the richest 45%. The results indicate that scholars of war should update the widespread prior belief that democracy, alone, causes peace.