Collective Rationality's Roots

This chapter argues that group actions are rational if the individual acts that constitute them are rational. It observes that individuals sometimes have conflicting goals and desires when they make decisions. The chapter goes on to acknowledge that some of the requirements that individuals can face align well with group efficiency, but that satisfying them can conflict with desires that the individuals may have quaqua individuals. The reverse is also possible. The chapter denies, however, that such cases reveal genuine conflicts between individual and collective rationality. Collective rationality does not demand individual efficiency in conditions that are not ideal for joint action. Furthermore, it is not irrational for individuals to make a trade-off between competing goals. In line with this, it argues that in the context of judgment aggregation, individuals can tolerate occasional inconsistencies without this entailing irrationality. The chapter concludes that individual rationality entails collective rationality.