Ancient Greek Music Theory in the Context of Historiography: Filling a Lacuna in the Study of the Greek Systema Teleion — The Music of Ancient Greece: An Encyclopaedia (1978) by Solon Michaelides

Ancient Greek Music in the Context of Its Revival During the Era of Humanism
During the era of humanism, spanning the period from approximately 1400 to 1600, people of various paths of life and disciplines displayed a keen interest in the discovery of the ancient fascination with learning, an endeavour which took those interested in this inquiry back in time to the centuries prior to the common era (B.C.E.), and as such to the Greek, Byzantine, Judaic, and Arabic traditions. 
This fascination and preoccupation with various disciplines, such as the quadrivium, comprising arithmetic, geometry, astronomy and music, and the trivium, comprising grammar, dialectics, and rhetoric, with the disciplines of the quadrivium and trivium also known as the artes liberales, key to the curriculum of the facultas artium, furthermore the artes mechanicae, 
and finally those disciplines located outside the realm of these two categories of classifications, such as theology, medicine, and law, all situated within the university curriculum, in turn rendered
invaluable insights into the theory and practice of each discipline identified during the Greek and Byzantine eras and also during the Middle Ages and the Renaissance.
With regard to the discipline of musica, the three strands of contemplation, that is, musica theorica, in reference to the abstract theory explored largely through Pythagorean arithmetic, musica practica, in reference to the art of composition and performance, and musica poetica were generally treated as separate entities in the written discourse, transmitted in manuscripts.
Even after 1480, the year of the publication of Franchino Gaffurio’s Theoricum opus musice discipline in Naples, the first published volume devoted to musica speculativa, as an alternative designation of musica theorica, to appear in print, theorists retained the strict separation of the two avenues of investigation, as is readily seen in the trilogy of Gaffurio (1451-1522), issued in Milan