Individual Coherence and Group Coherence

Paradoxes of individual coherence (e.g., the preface paradox for individual judgment) and group coherence (e.g., the doctrinal paradox for judgment aggregation) typically presuppose that deductive consistency is a coherence requirement for both individual and group judgment. This chapter introduces a new coherence requirement for (individual) full belief, and it explains how this new approach to individual coherence leads to an amelioration of the traditional paradoxes. In particular, it explains why this new coherence requirement gets around the standard doctrinal paradox. However, it also proves a new impossibility result, which reveals that (more complex) varieties of the doctrinal paradox can arise even for this new notion of coherence.