Louis Couturat as a Historian of Logic

Louis Couturat (1868-1914) is well known as the editor of Leibniz’s Opuscules et Fragments Inédits and for his study La Logique de Leibniz, which is often wrongly associated with his interpretation of Leibniz’s metaphysics. The confusion is twofold since both his book and his interpretation of Leibniz’s metaphysics are equally often identified with Russell’s famous interpretation, despite their remarkable differences. The purpose of this essay is to show that such confusions have obscured Couturat’s role as a historian of logic and, in particular, in relating the emerging systems of logic in the 19th century with the Leibnizian project of a characteristica universalis and a calculus ratiocinator. Couturat must therefore be seen as the oldest pioneer of van Heijenoort interpretation, according to which the new logic arises under two traditions, one with the idea of logic as a language and the other with the idea of logic as a pure logical calculus.