In liberal arts education, the quadrivium consists of the four subjects or arts, taught after teaching the trivium. The word is Latin, meaning four ways, and its use for the four subjects has been attributed to Boethius or Cassiodorus in the 6th century. Together, the trivium and the quadrivium comprised the seven liberal arts, as distinguished from the practical arts. according to geometric and harmonic principles, science – particularly geometry and astronomy – was linked directly to the divine. To seek these principles, therefore, would be to seek God. The quadrivium consisted of arithmetic, geometry, music, and astronomy. These followed the preparatory work of the trivium, consisting ofgrammar, logic, and rhetoric. In turn, the quadrivium was considered the foundation for the study of philosophy and theology. The quadrivium was the upper division of the medieval education in the liberal arts, which comprised arithmetic, geometry, music, and astronomy. Educationally, the trivium and the quadrivium imparted to the student the seven liberal arts of classical antiquity.
Origins
These four studies compose the secondary part of the curriculum outlined by Plato in The Republic and are described in the seventh book of that work. The quadrivium is implicit in early Pythagorean writings and in the De nuptiis of Martianus Capella, although the term quadrivium was not used until Boethius, early in the sixth century. As Proclus wrote:
The Pythagoreans considered all mathematical science to be divided into four parts: one half they marked off as concerned with quantity, the other half with magnitude; and each of these they posited as twofold. A quantity can be considered in regard to its character by itself or in its relation to another quantity, magnitudes as either stationary or in motion. Arithmetic, then, studies quantities as such, music the relations between quantities, geometry magnitude at rest, spherics magnitude inherently moving.
Medieval usage
At many medieval universities, this would have been the course leading to the degree of Master of Arts. After the MA, the student could enter for bachelor's degrees of the higher faculties. To this day, some of the postgraduate degree courses lead to the degree of Bachelor. The study was eclectic, approaching the philosophical objectives sought by considering it from each aspect of the quadrivium within the general structure demonstrated by Proclus, namely arithmetic and music on the one hand and geometry and cosmology on the other. The subject of music within the quadrivium was originally the classical subject of harmonics, in particular the study of the proportions between the musical intervals created by the division of a monochord. A relationship to music as actually practised was not part of this study, but the framework of classical harmonics would substantially influence the content and structure of music theory as practised in both European and Islamic cultures.