Decision Theory as Philosophy

Abstract

It is not easy to assess the extent to which decision theory constitutes a contribution to philosophy. On the one hand, the enthusiasts seem tirelessly to churn out highly technical Bayesian reconstructions of scientific practice. On the other hand, their opponents dismiss the result as a body of theory that is overidealized and falsely precise, bearing no important relation to the actual conduct of inquiry. And most philosophers seem happy to ignore the debate altogether and pursue a theory of inquiry as best they can. I take the opponents’ criticism seriously, but I am still an enthusiast. The aim of this paper is to explain why. The paper consists of an accessible argument for a Bayesian decision theory designed to enable any interested philosopher to see how the insights of decision theory provide, without idealization or false precision, a fundamental (and somewhat revolutionary) contribution to our understanding of the enterprise of rational inquiry.