This brief biography of J.-B Say puts in its context the thought of an author who was twenty-three years old in 1789. His social background is that of the Protestant Geneva. In the first part of his life, he founded a newspaper La Décade. His political action took the form of comments, reviews of articles and political statements published in La Décade. The originality of this action lies in the fact that he sought to invest the field of ideas in all its dimensions : the one of institutions, of elites and of the places of scientific research. J.-B. Say continues the tradition of the ideologists, through teaching activities. The Great Revolution demonstrates the power of people and of ideas on the course of events. The elaboration of the Traité d?Economie Politique and of the Cours Complet, cannot be understood without taking into account the various influences that contributed to shape the thought of Jean-Baptiste Say. JEL Codes : B12
