Economics and Philosophy (2019), 35, 423–459 doi:10.1017/S0266267118000469 ARTICLE The Allais paradox: what it became, what it really was, what it now suggests to us Philippe Mongin GREGHEC, 1 rue de la Libération, F-78350 Jouy-en-Josas, France Email:
[email protected] (Received 11 June 2018; revised 24 August 2018; accepted 27 August 2018; first published online 30 January 2019) Abstract Whereas many others have scrutinized the Allais paradox from a theoretical angle, we study the paradox from an historical perspective and link our findings to a suggestion as to how decision theory could make use of it today. We emphasize that Allais proposed the paradox as anormativeargument, concerned with ‘the rational man’ and not the ‘real man’,touse his words. Moreover, and more subtly, we argue that Allais had an unusual sense of the normative, being concerned not so much with the rationality of choices as with the rationality of the agent as a person. These two claims are buttressed by a detailed investigation – the first of its kind – of the 1952 Paris conference on risk, which set the context for the invention of the paradox, and a detailed reconstruction – also the first of its kind – of Allais’s specific normative argument from his numerous but allusive writings. The paper contrasts these interpretations of what the paradox historically represented, with how it generally came to function within decision theory from the late 1970s onwards: that is, as an empirical refutation of the expected utility hypothesis, and more specifically of the condition of von Neumann–Morgenstern independence that underlies that hypothesis.