Victoria Kahn’s Rhetoric, Prudence, and Skepticism in the Renaissance is well worth the read for anyone interested in the topic of political theology, virtue ethics, or the Renaissance and Reformation more broadly. She describes the nature of Renaissance concepts of prudence and rhetoric and its importance for the debate between Erasmus and Luther on the freedom of the will. Kahn explains:
Whereas the classical orator was trained to argue in utramque partem, that is, on both sides of a question, in any particular case he argued on one side or the other. But when the Renaissance humanist adopted the Aristotelian and Ciceronian rhetorical skills, he was not constrained by the same immediate concerns as is the orator in the forum or the law court. As a result he could actually present both cases and, in so doing, persuade the reader not to any specific action, but to the exercising of the prudential judgment that is required for all actions […] The distinction between deliberative and demonstrative rhetoric breaks down in the works of Quattrocento humanists not only because epideictic can be viewed as urging course of action, but also because the deliberation involved in reading is itself understood as a form of the deliberation that leads to action. The Renaissance humanists thus go beyond their mentors in conceiving of literature not only as the cause and effect of prudence and right action (i.e., the writer is presumed to be prudent and to inspire prudence in others), but as a form of prudence itself. Rhetoric here is not primarily conceived of in terms of style or ornament, but in terms of its capacity to exemplify and encourage the activity of practical reasoning. 1
Coluccio Salutati is a prime example of one who made use of this sort of rhetoric of prudence. Kahn elaborates:
In the Trecento Coluccio Salutati, chancellor of Florence from 1375 to 1406, is particularly eloquent on this point. In his early letter in praise of Petrarch, he argues that moral philosophy is inseparable from rhetoric (Ep. 1.179-80) not only because both are concerned with the practical realm of human affairs, but because it is in language that this moral dimension is most fully realized: language raises man above the animals and enables him to create a consensus and community, and language allows for the persuasion of the will to action. Accordingly, the poet and the orator do not perform a merely aesthetic function; rather, the aesthetic dimension is the precondition of the political.
The humanist concept of the inseparability of rhetoric and prudence played a crucial role in the debate between Erasmus and Martin Luther on the freedom of the will. Luther sees Erasmus’s use of rhetorical prudence to persuade the reader to come to their own conclusion regarding the freedom of the will as a form of skepticism. Luther argues:
That prudence of yours makes you veer about, determined not to commit yourself to either side, but to pass safely between Scylla and Charybdis; with the result that, finding yourself battered and buffeted by the waves in the midst of the sea, you assert everything you deny and deny everything you assert. 2
Luther uses the familiar metaphor of Scylla and Charybdis to argue that Erasmus has not “hit the mark” or found the “golden mean” as Aristotle would put it, but has in fact turned prudence into the excess of recklessness in judgment. This is the case, Luther believes, because the freedom of the will is not an indifferent matter to be left open to the judgment of the interpreter but is essential to the Gospel, “since on it both knowledge of oneself and the knowledge and glory of God quite vitally depend.” 3This does not mean, however, that Luther thought persuasion a futile task or that he rejected prudence. As Kahn argues, Luther and Erasmus actually used similar methods:
[B]oth Erasmus and Luther are concerned with redefining the notions of persuasion and debate as they are commonly understood. Just as Erasmus engages in a skeptical effort to suspend argument by means of argument, so Luther has his own way of doing away with the conditions of legitimate disagreement. Whereas Erasmus separates the authority of Scripture from the reader’s grasp of its meaning, Luther refers the reader to a principle of interpretive authority so transcendent that it is immanent. Although God is obscure to human knowledge, he argues, the meaning of His Scripture is perfectly accessible to man. 4