<p>Music was central to the medieval church's public worship: it was the essential medium of the Mass and the Divine Office. In this new critical edition, T. J. H. McCarthy presents the Latin text and the first English translation of Aribo's musical treatise, De musica and Sententiae. Written between 1070 and 1078, it is concerned with the workings of the liturgical music that Aribo and his contemporaries called Gregorian chant, and builds off of...