De ratione disserendi.
The Parts of Reasoning
Reasoning comprises invention and judgment as integral parts and demonstration, the probable, and the sophistic as divisive parts, with invention and judgment found together across all species of discursive reasoning.
The method of reasoning has two integral parts—invention and judgment—and two divisive parts: demonstration, the probable, and the sophistic. Demonstration deals with necessary arguments and belongs to philosophers. The probable belongs to dialecticians and rhetoricians; the sophistical, to sophists and quibblers. The probable is divided into dialectic and rhetoric, each of which has the integral parts, invention and judgment. For because they constitute the very genus—that is, the discursive—as a whole, it is necessary that in the combination of all its species they are found together at the same time. Invention is what teaches how to find arguments and construct lines of reasoning. Judgment is the knowledge of judging, which teaches how to evaluate each of those two. It can be asked whether invention and judgment are contained under philosophy.
Can Philosophy Contain All Knowledge?
Invention and judgment do not fit neatly under any of philosophy's recognized branches, prompting a distinction between knowledge as a discipline and knowledge as any cognition.
For they seem to fall under neither theoretical, nor practical, nor mechanical, nor logic — under which they might especially seem to fall. They are not contained under logic, because not through grammar and not through the disputative. They are not contained through the disputative, since they constitute it as a whole. But nothing can be at once an integral and a divisive part of the same genus. And so philosophy does not seem to contain every knowledge. But it must be known that knowledge is customarily taken in two ways: that is, for some discipline, as when I say dialectic is a knowledge, meaning an art or discipline; and for any cognition, as when I say someone who knows something has knowledge. For example: if I know dialectic, I have knowledge; and if I know how to swim, I have knowledge; and if I know that Socrates is the son of Sophroniscus, I have knowledge. And universally, everyone who knows something can be said to have knowledge.
Knowledge, Discipline, and Parts of a Whole
Every discipline and every cognition belongs to philosophy, though not in the same way; invention and judgment are parts of the discipline of disputation rather than self-contained disciplines themselves.
But there's a difference between saying 'dialectic is a branch of knowledge'—that is, an art or discipline—and saying 'knowing that Socrates is the son of Sophroniscus is a branch of knowledge,' that is, a piece of cognition. It's true to say that any branch of knowledge that is an art or discipline is a divisive part of philosophy, but it can't be said universally that every branch of knowledge that is a cognition is a divisive part of philosophy. Still, every branch of knowledge—whether it's a discipline or any kind of cognition whatsoever—is entirely a part of philosophy, either divisive or integral. A discipline, however, is a branch of knowledge that has its own self-contained end, in which the purpose of the art is fully worked out—something that doesn't apply to the branches of knowledge concerned with discovery or judgment, since neither of those is self-contained in itself, and therefore they can't be called disciplines, but rather parts of a discipline, that is, disputation.1 Again, it's asked whether discovery and judgment are the same parts of dialectic and rhetoric — which seems implausible, that two opposite kinds would be constituted by exactly the same parts. So it can be said that these two terms are used equivocally for the parts of dialectic and rhetoric—or, perhaps better, let's say that discovery and judgment are properly parts of disputation, and that under these terms they are used univocally, yet in the lower-level instances of this kind they differ from one another in certain specific respects.2 Yet those specific differences aren't picked out by these terms, because the terms don't refer to them insofar as they constitute species, but insofar as they are parts of a genus. Grammar is the knowledge of speaking without error; dialectic is sharp disputation that distinguishes true from false.
Rhetoric's Aim
Rhetoric is defined as the discipline directed toward persuasion in whatever form suits the task.
Rhetoric is the discipline aimed at persuasion — whatever form of it is suited to the task.
Read the original Latin
Ratio disserendi integrales partes habet inventionem et iudicium, divisivas vero demonstrationem, probabilem, sophisticam. demonstratio est in necessariis argumentis et pertinet ad philosophos. probabilis pertinet ad dialecticos et ad rhetores; sophistica, ad sophistas et cavillatores. probabilis dividitur in dialecticam et rhetoricam, quarum utraque integrales partes habet inventionem et iudicium. quia enim ipsum genus, id est, dissertivam, integraliter constituunt, necesse est ut in compositione omnium specierum eius simul inveniantur. inventio est quae docet invenire argumenta et constituere argumentationes. scientia iudicandi, quae de utroque iudicare docet. quaeri potest, si inventio et iudicium sub philosophia contineantur.
videntur enim neque sub theorica, neque sub practica, neque sub mechanica, neque sub logica, de qua magis videretur contineri. sub logica non continentur, quia neque per grammaticam neque per dissertivam. per dissertivam non continentur, cum integraliter eam constituant. nulla autem res esse possit simul integralis et divisiva pars eiusdem generis. sicque philosophia non omnem scientiam continere videtur. sed sciendum quod scientia duobus modis accipi solet, id est, pro aliqua disciplinarum, sicut cum dico dialecticam esse scientiam, id est, artem vel disciplinam, et pro qualibet cognitione, sicut cum dico scientiam habere eum qui scit aliquid. verbi gratia, si scio dialecticam, scientiam habeo, et si scio natare, scientiam habeo, et si scio Socratem esse Sophronisci filium, scientiam habeo. et universaliter omnis qui aliquid scit, potest dici scientiam habere.
sed tamen aliud est, cum dico, dialectica est scientia, id est, ars vel disciplina, atque aliud cum dico, scire quod Socrates est Sophronisci filius est scientia, id est, cognitio. de omni scientia quae est ars vel disciplina, verum est dicere quod sit pars philosophiae divisiva, non autem universaliter dici potest, quod omnis scientia quae est cognitio, pars sit philosophiae divisiva. est tamen prorsus omnis scientia sive disciplina sive quaelibet cognitio pars philosophiae, vel divisiva vel integralis. disciplina autem est scientia quae absolutum finem habet, in quo propositum artis perfecte explicatur, quod scientiae inveniendi vel iudicandi non convenit, quia neutra per se absoluta est, et ideo disciplina dici non possunt, sed partes disciplinae, id est dissertivae. rursum quaeritur si inventio et iudicium eaedem sint partes dialecticae et rhetoricae, quod inconveniens videtur, ut duo opposita genera eisdem prorsus constituantur partibus. dici ergo potest has duas voces aequivocas esse ad partes dialecticae et rhetoricae, vel, quod fortassis melius est, dicamus inventionem et iudicium proprie partes esse dissertivae et sub his vocibus univocari, in inferioribus tamen huius generis quibusdam proprietatibus, a se invicem differre. quae tamen differentiae per has voces non discernuntur, quia per eas non secundum hoc quod species componunt, sed secundum hoc quod partes sunt generis significantur. grammatica est scientia loquendi sine vitio; dialectica, disputatio acuta verum a falso distinguens.
rhetorica est disciplina ad persuadendum quaeque idonea.
Notes
- 1 ↩The Latin dissertivae is rendered here as 'disputation' following the context of dialectical/rhetorical method; the term carries a technical sense of argumentative discourse rather than the modern academic sense of a formal thesis defense.
- 2 ↩The distinction between aequivocas (equivocal) and univocari (univocal) usage is a technical point from Aristotelian logic; the author is arguing that 'discovery' and 'judgment' apply to dialectic and rhetoric not in the same sense but in related yet distinct senses.
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