The Knowledge Machine and the role of confirmation theory in science

The Knowledge Machine and the role of confirmation theory in science

Abstract

The inferential engine of science is the logic of evidential support, aka "confirmation". In 1945, Carl Hempel proposed a simple theory of confirmation that eventually came to be seen as unacceptably unsophisticated: it failed to incorporate the impact of epistemic context, of the "superempirical virtues" (such as simplicity, unity, explanatory elegance, and so on), and it was purely qualitative, telling you when a piece of evidence supported a hypothesis but without quantifying the degree of support. Drawing on ideas in The Knowledge Machine, I will propose that Hempel's theory, precisely because it is simplistic, comes much closer to capturing the logic of evidential support in science than is commonly supposed. From a philosophical perspective it is indeed unacceptable, yet it reflects many aspects of scientific practice very well. Or more exactly, what it reflects is the role of evidential support in scientific publication (as opposed to private scientific reasoning). Using the case of theoretical beauty, I will argue that the way support works in scientific publication is, indeed, strictly speaking irrational. Yet that irrationality, I will suggest, is critical to the success of modern science.