Practica Musicae utriusque cantus, excellentis Franchini Gaffori Laudensis quatuor libris modulatissima

Orators, Readers, Ambrosian, Gregorian

...expressing their concept in words rather than in melody, such as Orators and readers, and those who also modulate antiphons and psalms in divine services, which (though improperly) our Ambrosian and Gregorian clergy call plain chant, since they pronounce individual notes simply and plainly with an equal measure of short time. For it is not known to preserve the nature of concinnity, but rather that the limits and boundaries of certain modes themselves (which they also call tones), and the gatherings and transitions of voices, are known to be observed according to the natural disposition of the diatonic genus; the beginnings of the songs and of the entire modulation are for the most part proven in this. Hence, I call this plain chant a sound-bearing reading, as it were, sustaining sounds or substituted for the sounds themselves. The ancients, however, as Aristotle asserts in the twenty-eighth problem of the harmonic part, called the first observations of such voices, which they placed before adolescents who were being trained in music, the laws. The second genus is of those who pronounce not only the concept of the mind but also the syllables themselves, whether short or long (which is the way of poets), by metric consideration, about which there will be a free discussion in the first part of the second book. The third genus is of those who effect a melody and sweet song through either sonority or through certain dimensions of intervals; this is noted in the third volume of the present work, and these are properly called musicians and singers. The fourth genus is wont to be dedicated to the histrionic and mimic art, and to those who are moved by the gestures of the body to the imitation of the voice, such as in dances and choruses, to which Theophrastus ascribed a music approved in voice and body movement. But since this obscenity does not suit our ceremonies, we turn our mind to those things which concern divine praises. It is established, therefore, that Guido of Arezzo described his own fruitful introductory music with seven letters and six syllables naming the strings, adorned after the fashion of the fifteen strings of the natural and perfect diatonic system. It contributes indeed very much to the action of the human voice to imitate the concordant little strings struck on a lyre or cithara or monochord, of which the Greeks called some grave, others acute, and the rest middle. Truly, our ecclesiastics distinguish this tradition of Guido, which they call the hand, into grave, acute, and superacute, so that, with twenty-two lines and intervals or spaces inscribed alternately—having counted, of course, the tetrachord of the finemenon synemmenon / added string for the sake of imitation by joining two together—they call the first eight grave, as if closest to silence and taciturnity. They call the eight placed above these acute, and the remaining six superacute. Yet the acuteness itself exists in the eight grave strings, and gravity in the acute ones. Hence it is that a consonance springs from the heap of each of them, which Boetius used to define as the mixture of acute and grave sounds, falling upon the ears sweetly and uniformly. Therefore, the order of the voices deduced by seven letters through lines and spaces is taken as follows: for in the most grave place of the introductory, which a certain line marks, they have ascribed the Greek letter Γ Gamma and then the syllable ut. And in the nearer space, the letter A and the syllable re. In the second line following toward the acute, the square letter B conjoined with the doubled Γ conversely, and the syllable mi. But in the following interval toward the acute, they placed the letter C and the syllable fa. For I understand an interval or space as an empty margin interjected between two lines by acuteness and gravity. And they annotated the letters themselves and the seven syllables of the hexachord to the strings with a similar progression, but many things about these places would be sought here, which, since they have been clearly deduced in the fifth book of Theory, we have decided to pass over in silence for the sake of brevity. And let the diatonic introductory of Guido, with letters and syllables described by lines and spaces, be arranged in this paragraph.

Aristotle

Who are musicians and singers

Theophrastus

Guido

Greeks