Once you get past the spurious Ars musice of Thomas Aquinas, his references to music are elliptical and occasionally contradictory. One, however, may be brought into alignment with what we know about surviving music from the long thirteenth century. In the Sententia libri Ethicorum (Liber 10, Lectio 4), Aquinas’ gloss on Aristotle goes as follows: ‘ille qui non est iustus, non potest delectari delectatione quae est propria iusti, sicut nec ille qui non est musicus potest delectari delectatione musici’. Music is introduced as an exemplum to illustrate how the unjust can not enjoy the pleasures of the just in the same way that ille qui non est musicus can not enjoy the pleasures of the musician.
The association of music and pleasure opens up a route into thinking about surviving music – the symbols that live on in the medieval manuscripts from the most luxurious to the most ephemeral – and the ways in which ille qui est musicus might derive pleasure from this surviving music and the other arts. Aquinas only chose the musicus as his example because that is what is in Aristotle’s original text, but he might just as easily have chosen an artist or a poet; both author and commentator end ‘Et idem est de aliis delectationibus’ It is therefore in the links between music, painting and poetry – as well as a host of other arts – that we might be able to seek out what the pleasures of music might be.
The study of music has taken as read, if not for granted, the intertextual links between for example vernacular song and the prose romance or between Biblical texts, plainsong and the polyphonic music of the late twelfth century that took its name from the cathedral in which it was thought to be performed. But switching focus away from particular genres – organum, motet, conductus, rhymed office, sequence – and the ways in which we think they interrelate, and towards the actors and actants (terms borrowed from Becker and Latour) that enable and animate these intertextual links is to set up a very different history of music. Music and its sibling disciplines in the long thirteenth century can be seen to provide pleasure not only to concepts of the vernacular and of the liturgical, but also to Latin poetry and prose theory, the process of contrafactum (writing a new text often in a new language to existing music), as well as to such more technically musical questions as the emergence of metrical rhythm.