It may not always seem obvious to begin a study of French music in the Renaissance with a reference from the theoretical field. By entitling his study ‘Ut musica poesis’ Howard Mayer Brown attempted to remedy this shortcoming. However, without in any way disparaging his work, this results in a series of paradoxes and uncertainties about the links which in France during the Renaissance period unite musical practice and musical thought, whether this be philosophical or theoretical. It is true that expressions like ‘musical renaissance’ or ‘musical humanism’, easy and pernicious terms, have a hard time in the French field. And it is precisely because these terms are easy and pernicious that they can be used in this way. For while there has never been any question of doubting the role of French composers in constructing the musical landscape of the Renaissance, it has never, on the other hand, been imaginable to write a history of humanism in French musical thinking of the Renaissance. It is rather as if, causing a sudden break in the course of history, French writers and theorists of the fifteenth and sixteenth centuries had abandoned the art of sound to the practitioners, composers and performers alone. But no Western culture exists which can have a musical life without thought, and without the will to discover in it a pretext, a paradigmatic function or even an experimental field.