(fl mid-12th century). Cistercian music theorist and monk. He is believed to be the author of Regule de arte musica, the earliest Cistercian treatise on music theory.
The mid-12th-century Cistercian tonary Tonale Sancti Bernardi advises anyone seeking more information on certain theoretical topics to consult ‘the book on music’ that Guido of Eu wrote for his mentor, Guillaume, Abbot of Rievaulx. A music treatise is also attributed to Guido of Eu in the 13th-century catalogue of Richart de Fournival’s library. There is strong evidence that this book should be identified with a treatise Regule de arte musica (in F-Psg 2284), attributed in its explicit to an abbot Guido (‘Expliciunt regule domni Guidonis abbatis de arte musica’). Besides the suggestive coincidence of the name Guido, the Regule is addressed to a distinguished cleric, a master of the novices at Clairvaux, who had encouraged the author’s chant studies, which fits with the tonary’s mention of a dedicatee. The connection between Guido of Eu and the Regule is further strengthened by a 15th-century English treatise that quotes extensively from the Regule and credits that material to Guido of Eu (see Sweeney, 1982, p.90). There is thus strong circumstantial evidence to link the music theorist Guido of Eu, named in the Cistercian tonary, with the Abbot Guido, named in the explicit to the Regule de arte musica in its sole surviving source.
There is some question whether Guido of Eu should also be credited with another central Cistercian document on music, the official Preface to the Cistercian Gradual (Prefatio seu tractatus de cantu). This preface transmits doctrines of the Regule, in more condensed form and in heightened rhetorical language. Relying on attributions in late manuscripts, scholars of the 17th to 19th centuries assigned it to an Abbot Guido of Cherlieu (Guido Cariloci). In his edition of the Regule, Coussemaker appropriated the attribution of the preface, but misread the place name as Caroli-loco and thus inadvertently assigned the treatise to an undocumented Abbot Guido of Châlis. The traditional attribution of the preface concords with records from Cherlieu Abbey, which document an Abbot Guido there from 1132 to 1157. However, the most recent editor of the preface (Guentner, 1974) cautiously identified the author as an anonymous Cistercian.
The view that Guido of Eu (to whom the Regule is ascribed) and Abbot Guido of Cherlieu (to whom the preface to the Cistercian Gradual is ascribed) were the same person has gained wide acceptance. Admittedly, the tendency of the 12th-century Cistercian writings on music to present their distinctive doctrines as impersonal, institutional and grounded in authentic tradition has obscured the identities of those specific individuals who carried out radical chant reforms based on prescriptive theoretical doctrines. What is clear is that the Regule, which dates from the early 1130s, lays the foundation for the Gradual preface as well as for all the other official Cisterian music treatises, and that its premises guided the reform of the Cistercian Antiphoner and Gradual. The consistency of doctrine between the Regule and the preface favours a single author with dual names, one reflecting his place of origin (Guido of Eu), the other indicating a monastic career (Abbot Guido of Cherlieu), but it is also possible that the author of the preface was a disciple of Guido of Eu.
The Regule
concentrates on plainchant theory. It begins with the gamut, tetrachords,
intervals and species of consonance, and proceeds to an extensive discussion of
mode, or, to use the author’s term, maneria. The premises put forth in
this treatise, which include acceptance of all seven pitches as finals,
avoidance of B
and
limitation of the ambitus of any regular chant to ten pitches, provided the
foundation for an extensive revision of the Cistercian chant repertory. It is
highly probable that Guido of Eu was involved in the movement for reform, which
sought to correct the corrupt received repertory by bringing all chants sung in
the Cistercian liturgy into accord with authoritative theoretical principles.
In the sole extant manuscript (F-Psg 2284), the Regule is followed by a brief discant treatise that puts forward rules for the movement of two voices from one perfect consonance to another. The typical rule is framed thus: ‘If the cantus ascends a 2nd and the organum begins at the octave, when the organal voice has descended a 3rd, it will be at the 5th’. Since the discant rules begin after the explicit, and since the Cistercians looked unfavourably on the practice of polyphony, this section is generally regarded as a late accretion, to be separated from the Regule and its author. Yet it would seem to be at least coeval with the Regule, for its content and formulaic rules for two-part voice-leading ally it with other discant manuals from the mid-12th century. The evidence does not permit a firm conclusion about how this modest discant supplement came to be associated with the Regule or who was responsible for it.
See also Cistercian monks and Discant.
FasquelleE
CoussemakerS, ii, 150–91 [edn of Regule de arte musica]; 191–2 [edn of discant treatise]
GerbertS, ii, 265–77 [edn of Cistercian tonary, Tonale Sancti Bernardi]
J. Canal: ‘Sobre el autor del antifonario cisterciense’, Ephemerides liturgicae, lxxiv (1960), 36
K.-J. Sachs: ‘Zur Tradition der Klangschritt-Lehre: die Texte mit der Formel “Si cantus ascendit …” und ihre Verwandten’, AMw, xxviii (1971), 233–70
F.J. Guentner: Epistola S. Bernardi et Tractatus, CSM, xxiv (1974) [edn of preface to the Cistercian gradual, Cantum quem Cisterciensis ordinis]
C. Sweeney: ‘John Wylde and the Musica Guidonis’, MD, xxix (1975), 43–59
C. Maître: ‘Recherches sur les Regule de Arte Musica de Gui d’Eu’, Les sources en musicologie (Paris, 1981), 79–86
C. Sweeney: Johannis Wylde Musica Manualis cum Tonale, CSM, xxviii (1982)
C. Sweeney: ‘The Regulae Organi Guidonis Abbatis and 12th Century Organum/Discant Treatises’, MD, xliii (1989), 7–31 [edn of discant treatise]
C. Maître: La réforme cistercienne du plain-chant: étude d’un traité théorique (Brecht, 1995) [edn of Regule de arte musica, pp.108–233]
SARAH FULLER