In the introductory post, I mentioned how the first pentatonic example I wrote, combined with the free flow of the melody, somehow ended up resembling a Western chant, which inspired me to start this research and brought me to a stream of scholarly thought, where pentatonic scale is seen as the underlying framework of the Gregorian chant.
This link is not surprising, since, as I’ve mentioned before, pentatonic scale is common to early cultures through the world. Beside the Far Eastern and Celtic cultures, Engel (1870: 138, 153-57), Gavaert (1875: 4-5), Helmholtz (1890: 257-258), Riemann (1916), Sachs (1943: 204, 218-221) and others suggest its relationship in the antiquity with the West and the Middle East, including the Greek, Assyrian and Egyptian music. Also, authors like Szabolcsi (1948: 309-13) and Sendrey (1969: 212) argue that early Hebraic melodies appeared to have been based largely on the pentatonic scale. Furthermore, Glantz (2008: 192-193) points out that the Nusach service for the weekday morning Amidah is based on the pentatonic scale – its original mode, and his theory asserts that Ashkenazi liturgical music repertoire is almost entirely under the pentatonic scale.
Regarding the Gregorian chant, Chailley proposes that its modality was an outgrowth of a pentatonic scale-structure (Porterfield, 2014: 144), in other words, that the traditional eight modes are extensions of pentatonicism. Saulnier (2003: 42-43) writes that it is especially seen in the oldest cantillations of the Latin repertoire, whose musical material is rudimentary, limited in the number of its scale degrees and in its ambitus:
“In these primitive melodies, a single degree assumes all architectural functions: it is the dominant of the composition, the final of the piece, and possibly the tenor (reciting note) of the Psalm.”
As he continues, if we group their most important degrees – first, second, fourth, fifth and sixth, there appears to be what he calls a pentatonic “mother-cell”. Saulnier (2003: 50-52) further describes the three middle degrees of the pentatonic scale as the three notes of the “mother-modes” of archaic psalmody, from which developed the modal evolution into the eight modes; The two lower degrees are the first finals to which the evolution of the archaic modality leads by means of the descent of the final, and the two higher degrees are the first dominant peaks reached by the ascent of the tenor.
As for Chailley’s ideas of the evolution from pentatonic scale to the eight modes, Shepherd (1977: 87-88) cites some of them:
Continuing on, drawing the analogy from the old Chinese music theory, the remaining tones and their half-steps are seen as ornamental, secondary tones called pien. While the five main, pentatonic tones represent the tonal relaxation, pien are characterized as non-structural, often absent or with a negligible weight. They are unstable tones with regard to intonation, with the half-steps representing tension. (Hansen, 2006: 112) Along this line, Reese (1940: 160-161) mentions how the pien-tones provide the reason for B-flat other than that of euphony and avoiding the tritone:
“The pien-tone theory, when its implications are fully worked out, shows that B flat is not merely a faintly undesirable substitute for B natural… but its peer: and the melodies themselves, with their frequent use of B flat, bear this out”
Although, purely pentatonic melodies, like Anima nostra, are rare in the Gregorian repertoire (Hansen, 2006: 112), as Reese (1940: 159-160) writes:
“Whether or not virtually the entire ancient repertoire was based on a pentatonic groundwork… the fact remains that a considerable number of Gregorian melodies are clearly pentatonic”.
Quoting Yasser, Shepherd (1977: 84-85) argues that even without displaying pure pentatonic formulae, there is often convincing evidence from opening phrases and subsequent motives that the pentatonic structure plays a generative role in that chant:
Of course, with many opposing this theory, the role of pentatonicism in the Gregorian chant is quite debatable. For example, among many attacks on this theory is that the passing, pien-tones are bound to destroy any feeling of pentatonicism, to which Shepherd (1977: 86) responds by drawing the parallel with the existence of chromatic passing notes in tonal music, which does not always imply the destruction of tonality and creation of atonality.
Without getting into these arguments, the same way we cannot deny that at least some pentatonic motifs are found not only in the Gregorian chant, but also other European and Oriental traditions, we cannot completely contradict that there isn’t at least some pentatonic idea in the Gregorian chants and the formation of the eight church modes. Even without being really pentatonic, there are evident layers of pentatonicism, at least in terms of the Gregorian chant being marked by a high degree of pentatonic feeling (Jeppesen, 1939: 69), which can be heard in chants like Communion In splendoribus, Gloria XV and many other.
Finally, what should be understood is that the Gregorian chant tradition is in reality the result of a long evolutionary process, its finalization being the concretization of the repertoire. (Schaefer, 2008: 161) Hence, depending on the specific chant and its place on this path of musical development, the sense of pentatonicism will also vary.
With that said, I conclude my six-part research. Next, you can take a look at my example of the pentatonic plainchant here.
 In this post, I will be looking only at the relationship between pentatonic scale and Gregorian chant, and not the Ambrosian and other chant traditions, because there is more material and discussion available for the former.
Engel, C. (1870) The Music of the most ancient nations, particularly of the Assyrians, Egyptians and Hebrews; with special reference to recent discoveries in Western Asia and in Egypt. (2nd ed.) London: John Murray, Albemarle Street.
Gevaert, F. A. (1875) Histoire et théorie de la musique de l’antiquité, Livre I: Notions générales. Gand: Typographie C. Annoot-Braeckman
Glantz, J. (2008) Leib Glantz, the man who spoke to God. Tel Aviv: Tel Aviv Institute for Jewish Liturgical Music.
Hansen, F. E. (2006) Layers of Musical Meaning. Denmark: Museum Tusculanum Press.
Helmholtz, H. L. F. (1895) On the Sensations of Tone as a Physiological Basis for the Theory of Music. (3rd ed.) Edited and translated by Ellis, A. J. London, New York: Longmans, Green, and Co.
Jeppesen, K. (1939) Counterpoint: The Polyphonic Vocal Style of the Sixteenth Century. Translated by Haydon, G. (1992) New York: Dover Publications, Inc.
Saulnier, D. (2003) Gregorian Chant: A Guide. Translated by Schaefer, E. Solesmes: Abbey St. Pierre.
Schaefer, E. (2008) Catholic Music Through the Ages: Balancing the Needs of a Worshipping Church. Chicago, Ill.: Hillenbrand Books.
Sendrey, A. (1969) Music in Ancient Israel. London: Vision.
Shepherd, J. (1977) ‘The Musical Coding of Ideologies’ In: Shepherd, J. et al. Whose Music? A Sociology of Musical Languages. London: Latimer.
Szabolcsi, B. (1948) ‘About Five-tone Scales in the Early Hebrew Melodies.’ In: Lowinger, S. and Scheiber, A. Ignace Goldziher Memorial Volume I. Budapest.