Despite having put the concept of HPS on the institutional map, N.R. Hanson’s distinctive account of the interdependence between history of science and philosophy of science has been mostly forgotten, and misinterpreted where it is remembered. It is argued that Hanson’s account is worthy of renewed attention and extension since, through its special emphasis on a variety of different normative criteria, it provides the framework for a fruitful and transformative interaction between the two disciplines. This essay also examines two separate (...) threads of Hanson’s account of philosophy of science: his analysis of the conceptual dynamics of science and of the interrelation of the history and philosophy of science. While the two strands appear incongruent, and were perhaps inconsistent, a new interpretation of them is offered which is both consistent with Hanson’s fundamental intuitions and defensible in its own right. It is demonstrated that Hanson’s account compares favorably with those of Kuhn and Lakatos, and that it may provide a constructive means of scaling the barriers erected by fears of the genetic fallacy and ‘whiggish’ history. (shrink)