Abstract
Thagard provides a review and assessment of central aspects of rationality in science, dealing first with the traditional question: What is the nature of the reasoning by which individual scientists accept and reject conflicting hypotheses? He also discusses the nature of practical reason in science and then turns to the question of the nature of group rationality in science. In this latter context, Thagard discusses, among other matters, his CCC model, which shows how epistemic group rationality can arise in agents who communicate with each other while focusing on the explanation of observed phenomena. In the remainder of the chapter he examines whether scientists are in fact rational, that is, whether they conform to normative standards of individual and group rationality. He considers various psychological and sociological factors that have been taken to undermine the rationality of science.