The history of the relationships between rhetoric and music remains in part still to be written for the late Middle Ages. If music historians have investigated the autonomization of a musical theory starting from linguistic bases, the study of the Ars dictaminis demonstrates that in the thirteenth century, the thought, use, and ideology of dictamen were strongly conditioned by a perception of rhetoric as a musical art. The study of the theoretical explanations and of notarial practice suggests two possible approaches: the thought and practice of rhythmic ornamentation; the representation of dictamen as the music of notarial self-presentation.