Jehan des Murs, Astronomer and Music Theorist

GB-Lbl Burney 275, f. 390v. For full size image and detail, click here:









At the recent 2015 International Medieval Congress in Kalamazoo, Michigan, I had a chance to present some of my new work on Jehan des Murs, astronomer and music theorist, that I’m working on as a chapter of my monograph Greedy for New Things: Novelty in Music c. 1300-1340. Serendipitously, I presented my paper on May 14. On the afternoon of that exact date 632 years ago, Jehan observed a solar eclipse in the presence of Jeanne de France, the twenty-one-year-old Queen of Navarre – I opened my paper with a description of this event. They observed the eclipse in a castle that Jeanne had commissioned to be built in Saint-Germain, Évreux, but reportedly had named ‘Navarre’ (this name might give musicologists pause, given that minims were supposedly ‘invented’ in Navarre!).

In my paper I addressed the chronology of Jehan’s writings on music theory in light of revised chronologies of his astronomical and astrological works, and I also considered two aspects of Jehan’s scientific orientation that contextualise his work in music theory-namely, how he negotiates the novelty of his work with respect to that of prior authorities (his auctoritates), and his propensity for continuously revising and recasting his writings in order to cater for particular audiences.  An abstract of the paper follows, and stay tuned for more in my forthcoming book!

Although he wrote at least two and possibly four substantial music treatises in the 1320s, Jehan des Murs’s primary preoccupation at the beginning of his career appears to have been with figuring out and disseminating within Paris a new system of astronomy devised in the court of Alfonso X in Toledo. Recent scholarship on Jehan’s writings on astronomy offers a more accurate chronology of his output and activity than was the case in 1970 when Ulrich Michels published on the music treatises. We now have a greater understanding of Jehan’s central role in the introduction and development of Alfonsine astronomony in Western Europe—a system that was to hold say until the revolution of the Copernican heliocentric model. This paper reconciles the facts we know of Jehan’s biography with these new assessments of Jehan’s activity as an astronomer in the 1320s. Jehan’s tables of the stars’ and planets’ positions, based upon the experiential data gathered from his own observations made using the latest technologies, along with the new methods he devised for allowing others to easily calculate planetary longitudes, finally offered the possibility of a more precise and accurate calendar. And although Jehan nominally acknowledges his debt to older scholars (in much the same way as he does in Notitia artis musicae), he is more concerned with recording the true positions of the celestial bodies and precisely measuring reality than he is in ‘standing on the shoulders’ of those who have gone before. His writing betrays a confidence (and some might say arrogance) about the veracity and importance of his work and his conclusions. This paper contends that a similar attitude pervaded Jehan’s work as a music theorist where the aim is to more precisely measure, and indeed reform the entire system of musical time with one more clearly based upon the physical reality of sound and time as a sensibly perceived, and a lack of concern with appeasing those invested in older, less accurate, systems.

The ‘Partes prolationis’ of Jehan des Murs

I delivered a paper on a newly-transcribed fourteenth-century treatise on mensurable music (possibly written by Jehan des Murs) at the 42nd Medieval and Renaissance Music Conference held at the University of Birmingham, 3-6 July 2014. I hope to put the text of the treatise online when I have it fully transcribed: so far I have about 85% of its text deciphered. What follows below is the paper abstract, a works cited list, and a video of my presentation slides with an audio recording of my paper.


Within the mid-fourteenth century Parisian manuscript F-Pn lat. 7378A, three as yet unedited music treatises are found, copied in a tiny, highly abbreviated script in a section of the manuscript devoted mostly to the music treatises of Jehan des Murs. The incipits of the three treatises are as follows: ‘Omnes homines scire desiderant’; ‘Partes prolationis quot sunt’ and ‘Celebranda divina sunt officia in ecclesia’. Lawrence Gushee suggested that Jehan des Murs may be their author, since des Murs listed a book loan of a work authored by him with incipit ‘Omnes homines’ in the Escorial manuscript (O.II.10) that contains his autograph annotations. This paper considers the content of the second treatise, which appears to be closely related to Jehan des Murs’s own Compendium artis musicae. The Compendium begins: ‘Partes prolationis quot sunt? Quinque’ whereas the answer to the same opening question posed in the F-Pn lat. 7378A treatise is ‘Quattuor’. The text of this treatise is considered as a witness to early Ars nova theory as it relates to des Murs’s early works and to the transmission of these texts within the layer of F-Pn lat. 7378A that is devoted to works by des Murs (on both music and astronomy) and his contemporaries in these fields.

Works Cited

Chabás, José, and Bernard Goldstein. “John of Murs Revisited: The Kalendarium solis et lune for 1321.” Journal for the History of Astronomy 43 (2012): 412-37.
Chabás, José, and Bernard R. Goldstein. The Alfonsine Tables of Toledo. Vol. 8, Archimedes: New Studies in the History and Philosophy of Science and Technology. Dordrecht: Kluwer, 2003.
———. “Early Alfonsine Astronomy in Paris: The Tables of John Vimond (1320).” (2009): 207-94.
———. “John of Murs’s Tables of 1321.” Journal of Astronomy 40, no. 3 (2009): 297.
Desmond, Karen. “New Light on Jacobus, Author of Speculum musicae.” Plainsong and Medieval Music 9, no. 1 (2000): 19-40.
Goldstein, Bernard R., and David Pingree. Levi ben Gerson’s Prognostication for the Conjunction of 1345. Vol. 80/6, Transactions of the American Philosophical Society Held at Philadelphia for Promoting Useful Knowledge. Philadelphia: The American Philosophical Society, 1990.
Gushee, Lawrence. “Jehan des Murs and his Milieu.” In Musik – und die Geschichte der Philosophie und Naturwissenschaften im Mittelalter, edited by Frank Hentschel, 339-72. Leiden: Brill, 1998.
———. “New Sources for the Biography of Johannes de Muris.” Journal of the American Musicological Society 22 (1969): 3-26.
Hugonnard-Roche, H. L’oeuvre astronomique de Thémon Juif, maître parisien du XIVe siècle. Genève/Paris1973.
Jacquart, Danielle. “Rapport de la Table ronde Les disciplines du quadrivium (Paris et Oxford, XIIIe-XVe siècles).” In L’Enseignement des disciplines à la Faculté des arts, edited by Olga Weijers et al., 239-47. Leuven: Brepols, 1997.
Michels, Ulrich. Die Musiktraktate des Johannes de Muris. Vol. 8, Beihefte zum Archiv für Musikwissenschaft. Wiesbaden: F. Steiner, 1970.
Poulle, Emmanuel. “The Alfonsine Tables and Alfonso X of Castille.” Journal for the History of Astronomy 19 (1988): 97-113.
———. “Jean de Murs et les tables alphonsines.” Archives d’histoire doctrinale et littéraire du moyen âge 47 (1980): 241-71.
Rico, Gilles. “Music in the Arts Faculty of Paris in the Thirteenth and Early Fourteenth Centuries.” D. Phil. diss., Oxford University, 2005.
Ristory, Heinz. Denkmodelle zur französischen Mensuraltheorie des 14. Jahrhunderts. Vol. 81, Musicological Studies. Ottowa: The Institute of Mediaeval Music, 2004.
Thomson, Ron B. Jordanus de Nemore and the Mathematics of Astrolabes: De plana spera. Toronto: Pontifical Institute of Mediaeval Studies, 1978.
Tomasello, Andrew. Music and Ritual at Papal Avignon, 1309-1403. Ann Arbor, Michigan: UMI Research Press, 1983.
Wathey, Andrew, and Margaret Bent. “Vitry, Philippe de.” Grove Music Online. Oxford Music Online,
Werner, Eric. “The Mathematical Foundation of Philippe de Vitri’s “Ars nova”.” Journal of the American Musicological Society 9 (1956): 128-32.