Abstract

The classification of 9/8 as epimoric ratio is not only a basic arithmetical notion, but also an important technical ground for Pythagorean- Platonic musical theory. Why then does Theon of Smyrna avoid this point? The common explanation, which refers to Theon's inadequate technical knowledge, is unsatisfactory and aprioristic. A better solution can be found in the exegetical nature of the Expositio. Theon's technical perspective is inspired by a distinctive understanding of the "musical theory'' of the Timaeus.