Habent sua fata libelli.
--Maurus, De litteris, syllabis et metris
Traditional textual scholarship regarded manuscript witnesses as degenerate copies of the text the author intended; the critic's task was to eliminate the dross and recover the original. In his Essai de poetique medievale, however, Paul Zumthor saw the variation among manuscript copies of the "same" text as an essential characteristic of medieval writing; (1) as Bernard Cerquiglini put it in his Eloge de la variante, the task of the medieval scribe was not to copy but to rewrite. (2) Present-day textual scholarship, accordingly, sees surviving witnesses not as deficient copies but as versions of a text valid in their own right, whose meaning is determined not only by the words that make them up but by the company in which they are placed and the manner in which they are presented; as Andrew Taylor notes in Textual Situations, the "meaning" of a text is not fixed but evolves diachronically. (3) Though a lost original may be said to have a destiny, in fact that destiny consists of multiple threads. Each copy of a text acquires a destiny bound to the physical document that contains it and subject to reinterpretation by later generations, based not only on its original creation but also on the conditions under which it has survived.
Traditional historiography of music theory placed such value on the lost original that it not only devalued variants, but also typically ignored those compendia that are dependent almost exclusively on sources recognized as significant, most particularly when these bear attribution to a named author. The fame of the parent work that originally assured their creation and preservation would today assure their virtual anonymity.
Divina auxiliante gratia (hereafter Divina) is a fifteenth-century music theory compendium whose content is drawn exclusively from the Lucidarium of Marchetto of Padua, a seminal work on plainchant theory by the leading music theorist of the Italian Trecento. Traditional views would dismiss Divina as a mere stepchild of its distinguished parent, likely undeserving of an edition of its own. Should it be deemed to merit one, the convention of tradition would certainly relegate its variant readings to the bottom of the page. Yet a study of its six surviving sources clearly shows that in the fifteenth century, Divina could literally stand in for its famous parent, was indeed considered a viable substitute, and was generally given a privileged position and enhanced decoration in its host manuscripts. Moreover, two redactors treated the text with exceptional liberty; their treatments (discussed below) are noteworthy, but cannot easily be accommodated in a conventional edition.
Divina's six manuscript sources confirm the distinction of Marchetto's reputation; in addition, they further corroborate the importance and necessity of the plainchant theory during the late Middle Ages and the Renaissance--importance and necessity that, though long recognized, have often been obscured by scholarly fascination with the concurrent development of polyphony. These sources also provide important evidence that compendia often have intentional design and purpose (though both may appear haphazard at first glance), as do the manuscripts that house them; and that a text's physical position in a manuscript and the size and decoration of its initials not only reflect the redactors' plans but also reveal a sense of the importance of particular works.
Marchetto of Padua and his French contemporary Johannes de Muris were the preeminent music theorists of the fourteenth century. Both were influential for centuries, and the manuscript traditions of their works are entwined; the manuscripts considered here are typical in that respect. As I will make abundant reference to both in this essay, I will sketch their careers and influence at the outset, (4) beginning with Johannes, since the brief biography of Marchetto directly returns the discussion to Divina. …