Speculations about the potestas litterarum in Medieval grammar (11th through 13th centuries)

The aim of this paper is to study the concept of potestas, one of the three 'accidents' of letters in the Roman tradition. More specifically, it intends to examine the way which the speculative grammarians from the 11th to the 13th centuries dealt with speech sounds and which issues were attached to it. To commentators of the beginning of this period mapped out to the route to be followed in the attempt at a through explanation and systematization of Priscian's adumbrations. To that purpose, they forged the successful term modus pronunciandi and classified to potestas into five types. This chapter was granted as much discussion as any other: some concepts and terminology of the Aristotelian universe were employed in it (e.g., the opposition substantial/accidental, potentiality/act). Nevertheless, some remarkable differences between the points of view of the 12th century grammarians and those of the 13th-century have been observed, among them the interest on the part of the latter in the generation of the sound. In this century, two works, the anonymous Tractatus de grammatica and John Dacus's modistic Summa, held for different reasons a very particular position in the evolution of the doctrine on the potestas. In this respect, the influence of the former on the latter has been noticed. With their speculations all these medieval grammarians succeeded in differentiating two levels within the realm of speech sounds.