The Structure of Scientific Revolutions, by Thomas Samuel Kuhn (1922–1996), descended upon us like a whirlwind; it utterly transformed pivotal issues in the history and philosophy of science, especially in the field of methodology. Just a list of the terms Kuhn introduced – pre-paradigm, paradigm, normal science and puzzle solving, anomaly, crisis, revolutionary change, incommensurability, textbook-derived tradition – tells by now an old and familiar story. I have little to add to that story – not directly, anyway. This is not because that story led to settled conclusions; hardly any book of any significance does that, let alone Kuhn's book. Rather, what I want to do, in this chapter, is to use some of Kuhn's intriguing concepts and theories in order to fashion out of them – something Kuhn himself never did – a theory of group rationality. My hope is that this will lead to a reexamination of his beguiling texts, for this reason: Kuhn's distinctive subjectivist view of group rationality offers a unique – startling, truth to tell – view of the philosophical landscape.

In Section I, I turn my attention to Kuhn's subjectivist view and discuss the role of five key values in scientific decision making and the impact of these values on the group of scientists. In Section II, I delineate how the group makes transitions to various stages that are epistemically interesting and how the group effectively distributes the epistemic risks among its individual members.