ABSTRACT
Within the literatures of cognitive and developmental psychology, reasoning is generally construed as a process that takes place in an individual mind. An emerging literature, however, suggests that argumentation among people can be construed as a process of collaborative reasoning. This chapter reviews evidence that when small groups engage in reasoning they are sometimes more rational than any of their individual members. Of course it is also true that groups can be less rational than their members. Examination of the conditions that foster group rationality suggests the importance of respect for reasons and persons. It appears that rationality can be enhanced through argumentation, but the possibility and quality of argumentation depend on the size, circumstances, and functioning of the group, including the respect of group members for each other’s intellectual freedom.
