In 1691 Augustin-Charles D’Aviler published his Cours d’architecture qui comprend les ordres de Vignole. Ostensibly one of the many extended editions of Vignola’s Regola delli cinque ordini d’architettura (1562) that would appear over the course of the 16th and 17th century, D’Aviler’s Cours is in fact an expansive and not always systematic compendium on design and construction, covering subjects ranging from the design of locks to the layout of the princely residence. Still, the Cours opens with a short biography of Vignola and is dedicated for its first part to the five orders discussed by the Italian architect. But before D’Aviler dives into the proportions of the Tuscan order, the first and lowest of the five, he treats an altogether different subject: mouldings. Over three sections D’Aviler develops a small design theory of the subject: “des moulures, et de la manière de les bien profiler”, “des ornemens des moulures” and “du choix des profiles”. A closer look at these sections will show how D’Aviler deals with concerns and anxieties related to the two foundational creative acts of classicism: imitation and invention. The moulding is an architectural element that allows D’Aviler to explore the tension between these two creative acts, thanks to its intricate composition and its capacity to articulate the surface of a building. He does so in the pages of a printed treatise. This medium frames the matters of imitation and invention in terms of literacy and replication. D’Aviler constructs in words and image a vocabulary that allows for the reproduction of the principles he proposes. Thanks to the medium of the treatise, these principles can be taught and reproduced, an effect most apparent in the considerable afterlife of his theory of mouldings.