The 'Quatour pincipalia musicae': A critical edition and translation, with introduction and commentary

The dissertation is an examination, discussion, critical edition, and English translation with commentary of one of the most important music theory treatises written in Britain in the fourteenth century. Based on codicological evidence found in thirteen manuscripts, discussions of English Franciscan history, examination of one of the earliest convent library catalogues compiled by the Oxford Franciscans, and availability of sources in Britain at the time the Quatuor principalia was written, the dissertation proposes an authorship for a treatise commonly viewed as anonymous: it is the work of John of Tewkesbury, a Franciscan active at Oxford between ca. 1351 and 1392 who was also the maker and owner of the earliest extant copy of the treatise and the author of an astronomical work, De situ universorum.;The dissertation includes a discussion of the versions of the treatise, one lengthy and one contracted, and suggests that the lengthy version preceded the shorter one. The content and scope of the treatise are examined in light of the historical and philosophical context in which it was composed, and connections with other works of medieval music theory, both insular and Continental, are revealed.;A catalogue raisonne of the manuscripts of the treatise is included; the critical edition is based on the four English manuscripts that have preserved the text in its entirety and the one Continental manuscript that has preserved massive portions of the text.;The Quatuor principalia is a compilation of numerous earlier and contemporary sources and an important link in the transmission to Britain of Continental speculative music theory and the traditions of the ars antiqua and ars nova; it also includes the only known reference in an English source to an anonymous mid-fourteenth-century motet, Tant a souttille pointure/Bien pert qu'en moy n'a d'art point/Cuius pulcritudinem sol et luna mirantur. The Quatuor principalia is one of the several music theory treatises produced in England in the thirteenth and fourteenth centuries that can be used to argue in favor of a connection among the musical centers at Dover, Oxford, Bury St. Edmunds, and Canterbury.