The study seeks to uncover the musical thinking that produced three texts by different musical communities within a single historical period. Starting from the premise that in musical treatises such thinking may be revealed or concealed—that is, explicitly present, implicitly present, or excluded from consideration altogether—it aims to determine to what extent the musical dimension is preserved in scholarly texts. The three music treatises presented are: (1) a Latin Anonymous, (2) Book II (“Harmonics”) of the Treatise on the Four Sciences, or Quadrivium, by George Pachymeres, and (3) the Book of Circles by Safi al-Din al-Urmawi. Historically, the relationship between disciplina musica and musical thought is examined with reference to a period that was exceptionally formative for the entire Mediterranean and, in particular, for the interpretation of musical experience and for musical thought. The central question to which I seek an answer—philosophically, theoretically, and pedagogically—is why the Latin, Greek, and Arabic texts, all of which begin with the division of the string and thus appear to profess fidelity to ancient Greek musical science, are in their outcomes so different—indeed, different to the point of estrangement.