by Karen Desmond
Paper Presentation, Annual Meeting of the American Musicological Society, Philadelphia, November 2009.
Within the last twenty-five years a handful of scholars have emphasized the necessity of reading the texts of late... more
Within the last twenty-five years a handful of scholars have emphasized the necessity of reading the texts of late medieval music theory within the context of learning at the medieval university. In this paper, I examine how two central metaphysical debates of the late thirteenth century impacted both the new systematization of mensural notation proposed by the musician and mathematician Johannes de Muris in his Notitia, and the subsequent attacks on this new system by Jacobus, author of Speculum musicae. While certain ars nova treatises circulated as guides to specific technical problems of notation, Muris’s Notitia represents a whole-scale overhaul of mensural notation, systematizing it within a particular ontological framework. It is imperative that we have a full understanding of the frameworks within which Muris and Jacobus were operating, for only then can we hope to appreciate the proposed innovations, and the reasons for the irreconcilable issues between the two men.
The first metaphysical debate concerned the unity of form within being. The question was whether there existed a single form within man (Aquinas, Godfrey of Fontaines), or whether a plurality of forms existed simultaneously within one being (John Duns Scotus). A related debate looked at how qualities were understood to change: the plurality-of-forms proponents outlined a theory of change known as the additive theory while the unity-of-form adherents rejected this additive theory of change, believing that it assumed characteristics of qualities that were really only predicable of quantities, and proposed an alternative theory known as the succession-of-forms theory. While the references within the more well-known Book 7 of Speculum musicae to these debates are somewhat oblique, Jacobus makes specific and detailed references to them within chapters of Book 1 and Book 4. I analyze these passages within the context of the Quodlibets by Godfrey, Walter Burley’s De intensione et remissione formarum and the Ordinatio of Duns Scotus. This analysis will show Jacobus clearly advocating the unity-of-form position, and a close reading of the Notitia in this context will show how Muris developed his new systemization for mensural notation based on the Scotist position (which was further developed by John Dumbleton) that a plurality of forms may exist within one being, and that qualities change through addition or subtraction of degrees. For Muris, there is but one species of tempus, and within this one species there is a plurality of accidental forms, which are measured along one dimension. There are not different species of times, just greater and lesser times. The individual notes are individuated by the quantity of their matter, and whether parts are added or taken away from this individuating quantity of matter. Jacobus, on the other hand, holds onto the traditional explanation of the mensural system, conceptualized as a Porphyrian tree (like the arbor of Johannes de Burgundia) of the different species and sub-species of note values, each being distinct in their name, definition and essence, and each having an indivisible unity of form.
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