Since I keep returning to the question of the relationship between rhetoric and music (particularly after seeing an opera such as George Frideric Handel's Ariodante, whose performance depends so heavily on its suasive capabilities), I realized that it was time for me to return to the "Rhetoric and music" entry, which George J. Buelow had contributed to The New Grove Dictionary of Music and Musicians of 1980 (edited by Stanley Sadie). Reviewing this material made me realize that my longstanding interest in using the medieval trivium of logic, grammar, and rhetoric as a framework for the examination of both composition and performance probably had its roots in my having read this entry, probably within the first ten years of its appearance. (I recall meeting Buelow at a musicology conference and telling him how delighted I had been with his work along these lines.)
As Buelow observed, there is a long tradition of trying to apply the classical principle of rhetoric to musical composition:
In 1739, in Der vollkommene Capellmeister, Mattheson laid out a fully organized, rational plan of musical composition borrowed from those sections of rhetorical theory concerned with finding and presenting arguments: inventio (invention of an idea), dispositio (arrangement of the idea into parts of an oration), decoratio (the elaboration or decoration of the idea) – called elaboratio or elocutio by other writers – and pronuntiatio (the performance or delivery of the oration). Dressler's structure of exordium, medium, and finis was only a simplified version of the more usual sixfold division of the dispositio, which in classical rhetoric as well as in Mattheson consisted of exordium, narratio (statement of facts), divisio or propositio (forecast of main points in a speaker's favour), confirmatio (affirmative proof), confutatio (refutation or rebuttal) and peroratio or conclusio (conclusion).
While neither Mattheson nor any other Baroque theorist would have applied these rhetorical prescriptions rigidly to every musical composition, it is clear that such concepts not only aided composers to a varying degree but were self-evident to them as routine techniques in the compositional process.
For the record, since I did not mention it in yesterday's account, Ariodante received in first performance in London on January 8, 1735; so there is a good chance that Handel was one of the composers that Buelow had in mind in describing rhetorical concepts as "self-evident to them as routine techniques in the compositional process."
I bring up these details because they may throw some useful light on how composers like Handel applied that da capo aria form in the overall narrative flow of the plot. If we think in terms of all six elements of the dispositio, then it makes sense to think of narratio being provided by the recitative that precedes the aria. (The usual approach is to provide all of the "plot facts" in recitative and use the more musical sections to reflect on those "facts.") To the extent that there is an exordium, it would lie in the orchestral introduction to the aria, which means that the classical ordering of the elements is not strictly honored. The first part of the aria's ternary form then provides the divisio. The second part can then provide either a confirmatio or a confutatio, but rarely (if ever) both. (We encounter both in Ariodante, and we never encounter them both in the same aria. There is also a heavy bias in favor of confirmatio.) The peroratio is then the da capo section, basically structured as an iteration of the divisio in the context of the affirming or refuting material and possibly capped off with a coda. As I see it, there is a lot of sense in assuming that these structural details are nothing more than an attempt to represent practices that were routine to a composer like Handel (just as the classic source for training in counterpoint, the Gradus ad Parnassum by Johann Joseph Fux is best viewed as an attempt to represent the practices of Palestrina).
The other element of rhetorical theory that figures very heavily in musical composition (and must therefore be grasped in the activities of performance) is the decoratio, which I have written about in terms of embellishment. In writing about Ariodante's mad scene I also cited a "sighing motif," which, in technical language, is called an "affection." Much has been written about the extent to which such motifs provided a systematic "vocabulary of affections." Buelow, however, is not convinced:
It has been assumed incorrectly, especially by writers such a Pirro and Schweitzer and those influenced by them, that composers worked with stereotyped musical-rhetorical figures – analogous to the Wagnerian leitmotif – in order to create a predetermined form of tone-painting. Other writers including Bukofzer continued to believe that such a stereotyped set of musical figures was an essential aspect of a Baroque Affektenlehre. More recent research has clearly shown that a concept of stereotyped musical figures with specific affective connotations never existed in the Baroque composer's mind or in theoretical explanations. Musical-rhetorical figures were devices meant only to decorate and elaborate on a basic affective representation and to add dramatic musical stress to words and poetic concepts. They functioned in music just as figures of speech function in oratory – as part of the decoratio.
My guess is that the jury is still out on whether there really was a "vocabulary of affections;" and it will probably stay out in the absence of any way to get into the mind of any deceased composer! My personal feeling is that it makes just as much sense to assume that composers like Handel had "routine techniques" of decoratio as they had for dispositio, which is why the figures invoked in Ariodante's mad scene share a "perceptual category" with those applied to Ginevra's corresponding aria. If Buelow is trying to take issue with those who have tried to catalog such motifs, then the real object of his criticism may be later composers who would try to use such catalogs in a prescriptive capacity, when, as was the case with Fux's treatise, they were documented only for the sake of describing the practices of past masters. Thus, an appreciation (if not a thorough understanding) of the principles of both dispositio and decoratio can contribute much to being a better listener to Handel's music, particularly his settings of texts that have a dramatic element, as long as we recognize that theory is never a prescription for practice!