Although always about (1) the subject matter (2) the nature and (3) the ends, of the art, Mediaeval rhetoric was NOT a consistently unitary study. Nor have subsequent studies provided unitary and satisfactory understandings of the nuances of Mediaeval treatments. from Bradley.edu
I think this is an interesting idea. First, medieval rhetoric was no more consistent than the discipline of rhetoric is today–or, at least, as I perceive the discipline today.
The subject matter of rhetoric was a discussion in the Middle Ages, just as it is today. Which means that someone, at least rhetoricians, feel that rhetoric as a discipline is not as clearly understood as it ought to be.
The nature of rhetoric is also an interesting point, particularly if you look at different definitions of rhetoric, which I have done a little of and plan to do more of.
From the same post, “Rhetoric was used not only to discuss its own problems as subject matter, but also to work out disagreements in dialectic and theology.”
Many subordinated rhetoric to logic by finding it to be part of logic; or at least, by finding that it is about expression rather than discovery. Others by separating the differences between demonstration and probability. Others define the relationships among the various activities such that rhetoric simply gets “divided” out of important places.
Rhetoric was put to use in the Augustinian tradition as a way to further the work of divine eloquence and to further interpret their meanings. Especially as a way to re-align differences pointed out in textual hierarchies. In one of two ways: rhetoric becomes a part of logic (as that part of logic concerned with probabilities); or a part of theology (as the culmination of the trivium).
The ends of rhetoric are, obviously, the aims. Are we limiting rhetoric to persuasion or does rhetoric extend beyond persuasion?