Abstract

The aim of this paper is to examine in detail the similarities and dissimilarities between Werner Heisenberg’s account of closed theories and Thomas Kuhn’s model of scientific revolutions. My analysis draws on a little‐known discussion that took place between Heisenberg and Kuhn in 1963, in which Heisenberg, having just read Kuhn’s Structure of Scientific Revolutions, compares Kuhn’s views to his own account of closed theories. I conclude that while Heisenberg and Kuhn share a holist conception of theories, a revolutionary model of theory change, and even a notion of incommensurability, their views diverge fundamentally when it comes to the issue of scientific realism. I show that, contrary to popular opinion, Heisenberg is not an instrumentalist, but rather a pluralistic realist.