Review of Till Duppe and E. Roy Weintraub's Finding equilibrium: Debreu, McKenzie and the problem of scientific credit. Princeton: Princeton University Press, 2014, 304 pp.In an all-night session in early 1697 Isaac Newton solved two problems posed by Johann Bernoulli and Gottfried Leibniz as a challenge to the mathematical community. Newton sent the solutions to the Royal Society for anonymous publication. Despite Newton's self-effacing gesture, Bernoulli recognized the author from the proofs, and proclaimed, tanquam ex ungue leonem: we know the lion by his claw. In Till Duppe and Roy Weintraub's engaging and illuminating history of the mid-twentieth-century proofs of competitive general equilibrium and the three authors associated with them, the issue of the personality behind the proofs appears again and again. In this case, authorship is well known to us. Yet the role of personalities is hardly clear. The authors raised an interesting problem, and enlighten us with their investigation.Duppe and Weintraub's clearest contribution is to reveal the richness of the recently available archival material that surrounds the proofs. They provide evidence for what many conjectured: that Arrow and Debreu, despite writing together one of the most famous papers in economic theory, had very different aims. Weaving together archival and interview material, the authors convincingly demonstrate that Arrow's goal in his joint work with Debreu was to stress 'economic meaning' and, at that point, 'verifiability', while Debreu stressed mathematical formalism, technique, and generality. They quote Debreu as later saying that such theorizing is not a statement about the real world but is only an evaluation of a model. These are commitments the two Nobel Prize winners carried throughout their careers. McKenzie's story is far less known and revelations about him and his work are particularly welcome. Duppe and Weintraub do a real service by showing the hesitations and setbacks McKenzie had to overcome to publish his paper, and the struggle for recognition that he engaged in only partly successfully. Duppe and Weintraub relate numerous pertinent and illuminating facts, events, and conversations that surround these authors and the circles in which they traveled.The authors' methodological points will be controversial than their expansion of the historical record. I will focus on three claims regarding the personality of authors and their work.The first derives from the Mertonian observation that science aims for impersonal authoritativeness, yet credit for scientific discoveries is perforce personal. This sets up a tension that our protagonists to address. Should they maneuver to gain credit or simply be pleased by their contributions to the advancement of an overarching enterprise? Arrow is the clearest exponent of the anonymity and sociality of the enterprise. He writes that economic research is more and a cooperative matter, requiring teams of individuals trained along similar lines. He says of the proof, I had not done it, somebody else would have (p. 235). Duppe and Weintraub show that while Arrow tended toward this self-effacing position, Debreu and McKenzie, confidentially but persistently, hungered for the recognition and respect that comes from priority in publication-credit for work, appointments and recognitions at prestigious institutions, and prizes for a lifetime of achievement, most notably the Nobel Prize.Duppe and Weintraub are successful at showing us the tensions that arise between the norms of science and personal ambition. As with Newton, personality seems hard to stamp out. If a claw can be seen, it denotes a lion, not a mere mortal. The authors take Arrow's attitude at face value. They write that in contrast to the backbiting of Debreu in his priority battle with McKenzie, Arrow, instead, remained generous (p. 212). Arrow may well displayed such characteristics regardless of circumstance, but it is fair to point out that he got recognitions that others may deserved, and got them easily and earlier than the other two. …