Published online by Cambridge University Press: 24 November 2021
As we celebrate the centenary of John Maynard Keynes’s Treatise on Probability (1921), we are still faced with unresolved, fundamental questions about his foray into the philosophy of probability. One of these unresolved questions concerns whether Keynes (1931) later changed his mind in response to intense criticism from Frank Ramsey (1922, 1931) and abandoned the logical theory of probability. This essay draws from Cheryl Misak’s recent biography of Frank Ramsey (2020) to argue that Ramsey had an even wider influence on Keynes’s work than has been recognized, and that this influence was not just on his philosophy of probability but also on his economics. Understood in this fuller context, it seems even more clear that Keynes embraced and built upon Ramsey’s subjective theory of probability in The General Theory of Employment, Interest, and Money (1936).
I would like to thank an anonymous referee and Pedro Duarte for comments on an earlier version of this essay. All remaining errors are mine alone.