ABSTRACT
This essay examines the metaphysical category of ‘music’ in the Western tradition with special reference to Augustine’s De Musica (composed in AD 391). In his treatise on ‘the science of proper modulations’, Augustine codified what Boethius was later to call the quadrivium, the ‘fourfold path’, according to which mathematics was subdivided into arithmetic, geometry, music and astronomy.1 This curricular articulation was centred upon sciences of measurement: geometry measured inert, inorganic, sublunary spaces; music measured the relationship between the soul and the body (i.e. the proportions between the psychic and the organic), and also proportions within the soul itself; astronomy measured the time and movements of the heavenly bodies (often regarded as moved by the World Soul); and arithmetic, the most abstract, was the science of numbers in themselves. The order of these disciplines-the higher liberal arts-ascended through increasing degrees of abstraction from material to incorporeal contemplation, encouraging the knower towards the vision of God.2 However, in the tripartition of music itself, the first category, the musica mundana, overlapped in its concerns with astronomy, as the heavenly spheres were thought to compose through their movements and ratios a music unhearable by us.3 Moreover, as we shall see, because musical measurement is applied by Augustine even to God, on account of the relationality between the persons of the Trinity, the supremacy of arithmetic as transcending measure is implicitly surpassed. In this way, music becomes the science that most leads towards theology, and it is, perhaps, not accidental that Augustine’s only lengthy treatise on a single liberal art concerns music.
