- Rhetoric & Dialectic in the Time of Galileo
The core of this book consists of introductions to and abridged translations of six Renaissance works in Latin by Italian authors. Five are by Ludovico Carbone (1545-1597): Introduction to Logic (1597); The Tables of Cypriano Soarez's Art of Rhetoric (1589); On the Art of Speaking (1589); On Oratorical and Dialectical Invention (1589); and On Divine Rhetoric (1595). The sixth is Aristotle's Art of Rhetoric (1579) by Antonio Riccobono (1541-1599). The subject matter is clearly that cluster of fields known by such labels as logic, dialectic, and rhetoric; here logic means the theory and practice of demonstration, dialectic the theory and practice of probable reasoning, and rhetoric the theory and practice of persuasive argument. There is also a general introduction with two aims: (1) to contextualize these works in the history of logic-dialectic-rhetoric, by discussing the Aristotelian and medieval traditions and such other Renaissance authors as Lorenzo Valla, Rudolph Agricola, and Peter Ramus; (2) to apply these ideas to the Galileo affair (1613-1633) and advance an account I would label rhetorical. [End Page 323]
This book is clearly written, well documented, skillfully argued, and attractively produced. For this alone the authors should be commended. But it has other merits. One is that the material has greater significance than they realize insofar as it is of some relevance to that philosophical and cultural movement labeled informal logic and critical thinking. For example, the following definition of logic by Carbone would find favor with scholars in that field: "Logic is a habit that directs the operations of the mind; or, it is a science of beings of reason as they are directive of the intellect's operations. Or, it is a faculty that treats of the method by which things that are obscure are manifested by defining, things that are confused are discerned by distinguishing, and truths are confirmed and errors refuted by arguing" (p. 61).
A second merit is that their account of the Galileo affair is relatively novel and original, and this is no mean accomplishment in light of the countless pronouncements about this cause célèbre that have been advanced in the past four centuries. Thus their account deserves a brief summary: In 1616 the Church issued a decree forbidding Catholics to defend Copernicanism as true, because it was contrary to Scripture. After one of Galileo's admirers became Pope Urban VIII in 1623, Galileo felt he could resume his pro-Copernican cause as long as he did it discreetly. He tried this with the Dialogue on the Two Chief World Systems, Ptolemaic and Copernican (1632). Paying lip service to the decree, he claimed he was defending Copernicanism only as probable. He worked on three levels. Dialectically, he examined both Ptolemaic and Copernican arguments, concluding that the latter were stronger than the former. Logically, he argued that only the earth's motion could provide a physical explanation of why the tides occur, and that the demonstrative certainty of this argument could be undermined only by invoking divine omnipotence and saying that God could have created tides on a motionless earth. Rhetorically, Galileo disparaged Ptolemaic ideas, arguments, and authors with "figures such as ridicule, irony, analogy, metaphor, metonymy, prosopopoeia, and more" (p. 10). The effort did not succeed: Church authorities found his comparison of the relative merits of arguments on both sides biased toward Copernicanism; his tidal argument was found invalid; and his rhetoric was found offensive, especially by the pope. More generally, the authorities found the book to violate the separation among the three domains of demonstration, dialectic, and rhetoric. I would want to question several parts of this account, but that is beyond the scope of a brief review.