Quadrivium

 In liberal arts education, the quadrivium (plural: quadrivia^[1]) consists of the four subjects or arts (arithmetic, geometry, music, and astronomy) taught after 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.^[2][3] Together, the trivium and the quadrivium comprised the seven liberal arts (based on thinking skills),^[4] as distinguished from the practical arts (such as medicine and architecture) (Wikipedia).