The five canons of classical rhetoric are perhaps summed up best in this quote from the late Gerald M. Phillips, professor of speech from Pennsylvania State University:
"The classical Canons of Rhetoric specify the components of the communication act: inventing and arranging ideas, choosing and delivering clusters of words, and maintaining in memory a storehouse of ideas and repertoire of behaviors…
This breakdown is not as facile as it looks. The Canons have stood the test of time. They represent a legitimate taxonomy of processes. Instructors in our own time can situate their pedagogical strategies in each of the Canons."
The words of the Roman philosopher Cicero and the unknown author of "Rhetorica ad Herennium" break down the canons of rhetoric into five overlapping divisions of the rhetorical process:
1. Invention (Latin, inventio; Greek, heuresis)
Invention is the art of finding the appropriate arguments in any rhetorical situation. In his early treatise "De Inventione" (c. 84 BCE), Cicero defined invention as the "discovery of valid or seemingly valid arguments to render one's cause probable." In contemporary rhetoric, invention generally refers to a wide variety of research methods and discovery strategies. But to be effective, as Aristotle demonstrated 2,500 years ago, invention must also take into consideration the needs, interests, and background of the audience.
2. Arrangement (Latin, dispositio; Greek, taxis)
Arrangement refers to the parts of a speech or, more broadly, the structure of a text. In classical rhetoric, students were taught the distinctive parts of an oration. Although scholars didn't always agree on the number of parts, Cicero and the Roman rhetorician Quintilian identified these six:
- Exordium (or introduction)
- Partition (or division)
- Peroration (or conclusion)
In current-traditional rhetoric, arrangement has often been reduced to the three-part structure (introduction, body, conclusion) embodied by the five-paragraph theme.
3. Style (Latin, elocutio; Greek, lexis)
Style is the way in which something is spoken, written, or performed. Narrowly interpreted, style refers to word choice, sentence structures, and figures of speech. More broadly, style is considered a manifestation of the person speaking or writing. Quintilian identified three levels of style, each suited to one of the three primary functions of rhetoric:
- Plain style for instructing an audience.
- Middle style for moving an audience.
- Grand style for pleasing an audience.
4. Memory (Latin, memoria; Greek, mneme)
This canon includes all the methods and devices (including figures of speech) that can be used to aid and improve the memory. Roman rhetoricians made a distinction between natural memory (an innate ability) and artificial memory (particular techniques that enhanced natural abilities). Though often disregarded by composition specialists today, memory was a crucial aspect of classical systems of rhetoric, as English historian Frances A. Yates points out, "Memory is not a 'section' of Plato's treatise, as one part of the art of rhetoric; memory in the platonic sense is the groundwork of the whole."
5. Delivery (Latin, pronuntiato and actio; Greek, hypocrisis)
Delivery refers to the management of voice and gestures in oral discourse. Delivery, Cicero said in "De Oratore," "has the sole and supreme power in oratory; without it, a speaker of the highest mental capacity can be held in no esteem; while one of moderate abilities, with this qualification, may surpass even those of the highest talent." In written discourse today, delivery "means only one thing: the format and conventions of the final written product as it reaches the hands of the reader," says the late English professor and scholar, Robert J. Connors, from the University of New Hampshire.
Keep in mind that the five traditional canons are interrelated activities, not rigid formulas, rules, or categories. Though originally intended as aids to the composition and delivery of formal speeches, the canons are adaptable to many communicative situations, both in speech and in writing.
Connors, Robert J. "Actio: A Rehetoric of Written Delivery." Rhetorical Memory and Delivery: Classical Concepts for Contemporary Composition and Communication," edited by John Frederick Renolds, Lawrence Erlbaum Associates, 1993.
Phillips, Gerald M. Communication Incompetencies: A Theory of Training Oral Performance Behavior. Southern Illinois University Press, 1991.
Yates, Frances A. The Art of Memory. University of Chicago Press, 1966.