1 Pierre Dockès In the past, it was common to make public confessions about the seven deadly sins, especially in Calvinist country. So, why did I study the history of economic thought? Of course, greed was an essential motive. We all know how easy it is to become rich by practicing this subject! Besides, devouring Léon Walras' hundreds of pages is surely proof of gluttony. Honestly, there must also be a bit of sloth, this intellectual apathy in preferring to dig over ancient fields rather than clearing new ones. And a touch of lust, although always in a limited sense (even Casanova's economic works are deceptive in this respect), at least an attraction, an irresistible desire for an art that is caught between sport, play and the resolution of murder mysteries. Envy as well, the sort that is felt when looking at a neighbor's flourishing fields. Of course, since Bernard de Chartres’s time, we console ourselves by claiming to see further by standing on the shoulders of giants. When we see that today the dwarfs have come down, wrath arises! Finally of course, pride! But although I had given up hope of one day being crowned in a laurel wreath, happily, thanks to you, I have become an honorary member of ESHET. But, to be completely honest, I ask myself whether chance was responsible for my orientation. As is often the case, chance presided over my choice of thesis topic, L'espace de la pensée économique, simply because, in Lyon, Claude Ponsard was the supervisor you had to work with. He steered me towards spatial theory. To tackle this magnificent subject, I realize that I must go back to not only Thünen but much further than that, to authors from the 17th and 18th centuries who thought about economy in space. I started by writing a first historical chapter, and passion overcame intellectual sloth, so I continued and it became a thesis. Chance also steered me towards Léon Walras because, around the same time, I met William Jaffé on his final visit to Lyon. He told me that in 2 the damp university basements there were shoe boxes filled with Walras' archives; what we call the Lyon Collection. It was completely forgotten and nobody cared about it. I remember that I was shocked at such a disregard, but did not think to do something about them myself. It wasn't until two decades later, in 1983, that along with Potier, Goutte, Hébert, Mouchot and Servet, we were able to found the Centre Walras, what is now known as Triangle. At first, we only wanted to save and classify these archives. But, while researching Walras' unpublished works, we found two works in Montpellier that Léon Walras had prepared. They were bound in just a little piece of string and completely forgotten. Mélanges and Associations populaires had been waiting there for seventy years for us to open and publish them. Jean Pavleski offered to publish not only these two unpublished pieces but the whole work, and according to Léon's wishes, those of his father Auguste. That was in 1986 and we didn't finish until 2006. Twenty years! It was an exciting collective project, even if I sometimes regretted training the team in a trade that is academically undervalued. But this allowed me to write Society is not a picnic. Ah Léon Walras! Our relationship is like Charles Swann's love for Odette de Crécy in Proust's Swann's Way: "To think that I've wasted years of my life, that I've experienced my greatest love, for an economist who didn't appeal to me, who wasn't even my type. " “My type” at this time ? That was Marx and Schumpeter, two authors whose mistakes were as great as their genius! What irritated Bernard Rosier and me about Marx and Schumpeter was their “economism”, their dated fascination with "productive forces" and technological innovations. What interested us in them, though, was their "historical economics". In Capitalism, Socialism and Democracy, Schumpeter had this broad perspective "the economic theory of the future […] will be a theory […] of the economic process as it goes on, under its own steam, in historic time, producing at every instant that state which will of itself determine the next one. " In other words: "how economic theory may be turned into historical analysis and how the historical narrative may be turned into ‘histoire raisonnée’". I wrote Medieval Slavery and Liberation from this perspective. Similarly, along with Bernard Rosier, we wrote Rythmes économiques, which was Schumpeterian in subject and anti-Schumpeterian in analysis, as well as L'histoire ambiguë, a way of challenging the hubris of the philosophies of history. Hence my relationship with historians, with Duby, Braudel, Wallerstein, and finally an approach that is closer to Schmoller's or Karl Polany's school than what we expected! 3 This "reasoned history" and "historical economics" could not have been achieved without "intellectual history", in the words of Jean-Claude Perrot. As you know "For good or evil, the ideas of economists and political philosophers, both when they are right and when they are wrong, are more powerful than is commonly understood". Above all, today more than ever, we are looking for economic theory in the works of past authors. I have always thought that in the writing of authors of the “dead army”, sometimes even ancients ones, you could find theories that they were the only people to write or are still the only people to have explored them in depth. The phenomenon is even more striking as there has been a spectacular de-theorization, especially in comparison to the "high theory" period. In a first step, while modeling allowed precision and a certain amount of scientific legitimacy, it came at the price of a considerable simplification of the theory. In a second step, econometrics was carried out by abandoning the theory. And contemporary researchers must be content with this. The result is that in the rare instances where theory is still discussed, it is often at seminars on the history of economic thought. It seems quite telling to me that many economists who have become well-known in other fields come back to the history of thought as if they can finally come back to the essential questions. After my confessions about "why history of economic thought? " come the question of "how" ? To me, Richard Rorty and Mark Blaug's old distinction between historical and rational reconstructions seems weak for a number of reasons. Firstly because there are other possible reconstructions: that which revolves around the genealogy of ascending or descending concepts ; a reconstruction of the social or psychological conditions which explain the work's characteristics ; Michel Foucault's structural reading and Derrida's deconstruction. Next because an absolutist reconstruction assumes prior "contextualization" of any text to decode it, replacing the contemporary facts. You must always first try to understand what the author wanted to say, avoid misinterpretations, and, one by one, remove the "layers" of successive interpretations that the text gave rise to. We know that Blaug changed its position. It is also a public confession: “Although I have been guilty myself of the very sin I have just deplored, I have come to the conclusion that the only approach to the history of economic thought that respects the unique nature of the subject material […] is to labor at historical reconstructions, however difficult they are”. 4 The various approaches or reconstructions are all hermeneutics. As Carlo Guinzburg explained, historical research is like a police investigation. Finally, it is always about solving riddles. Rediscovering what an author wanted to say is like a puzzle. There are new puzzles that we can solve or put into perspective by searching in old texts. There are old puzzles which are still relevant today. There are even solutions which have only been provided by thinkers from the past. This is why I was passionate about Thomas Hobbes; because he gave me a solution to the problem of co-ordinating the agents that mobilize strategic analysis and the theory of agency. When you approach questions of power and authority in economics from a strategic point of view, Hobbes is still the authority. Not as a precursor to contemporary theory, not by dissecting rational reconstruction, but because he effectively provides a solution to the journey from a non-cooperative game to a cooperative game. Unlike philosophers or "hard" scientists, historians in economic sciences must have two irons in the fire. For philosophers, the thinkers of the past are just as alive as those from the present day. Philosophy is partly a history of philosophy. We are philosophizing when we read Platon or Spinoza. The rational approach is thus natural. When looking at the past, historians in "hard" sciences will generally only find "dead" segments, or analyses which only survive if integrated into modern theories. All is already in the present day science! So, there is no place for a rational history as the history of scientific thought is inevitably relativist. By reading Galileo or Newton, you are not performing astronomy or physics, just history. For the mathematician and philosopher Alfred Whitehead "A science which hesitates to forget its founders is lost". Economists are in an in-between situation; past knowledge is the "living dead". Many of the problems that they presented are ours too; the analyses that they developed are not all integrated into contemporary knowledge or they merit being revived. Some dishes are best when gently reheated. When contemporary economists ignore or look down on past, they are depriving themselves of an essential part of living economic knowledge which is just waiting to be revived. I conclude by asking for an epistemology that incorporates a large dose of methodological anarchism, à la Feyerabend : to recognize his "anything goes" which in the end is not far from : "It doesn't matter whether a cat is white or black, as long as it catches mice".