ters. Also, the transition from older to new historiography involves many nuances, and the causes by which historians would represent more or less the new or the old historical tradition depend on what would be considered relevant to the discussion. I have tried to identify some features of new historiography according to Kuhn's writings and, based on them, show that Duhem was a real contributor to historiographic change. But, the question that can be asked is: when did the change to which Kuhn refers in SSR begin? Kuhn's review of Koyré's work allows us to temporarily locate what he called the "historiographical revolution": a movement that began with Koyré himself. Kuhn (1970a, 67) writes: "More than any other single scholar, Koyré was responsible for the first stage of the historiographical revolution". But, as we know, a revolution is not the work of a single man. Kuhn indentified in SSR a group of historians. It was a group of younger scholars that was presenting a "philosophical and analytical approach to the history of science" (Crombie 1959, 164). Mary Hesse's review of SSR corroborates Kuhn's identification with a group: "My own impression is that Kuhn's thesis is amply illustrated by recent historiography of science and will find easier accessibility among historians than among philosophers" (Hesse 1963, 286). In fact, when we observe the works Kuhn cites in SSR, we can see that most of them were published in the 50's. His more cited masters had works published since 1930. We may also recall that in 1957, Kuhn was among more than seventy participating historians of the University of Wisconsin Congress, critically discussing problems in the history of science. Among them, there were some of those cited in SSR, such as Mashall Clagett, Rupert Hall, Giorgio de Santillana, A. C. Crombie, Derek J. S. Price, Henry Guerlac, Charles C. Gillispie and Marie Boas.39 In different degrees, among other historians, they were making the historiographic revolution. And Kuhn saw himself as a participant of it. Retreat