Definition
The five canons of rhetoric are the sequential activities a classical orator was trained to perform when preparing and delivering a speech. They are inventio (invention), dispositio (arrangement), elocutio (style), memoria (memory), and pronuntiatio or actio (delivery). The Romans, especially Cicero in De Oratore and the anonymous Rhetorica ad Herennium, gave the canons their canonical form; Quintilian's Institutio Oratoria turned them into a complete pedagogical curriculum.
The canons map the workflow from idea to performance. Invention is the search for available arguments and appeals; arrangement is their ordering into a coherent structure (usually exordium, narration, proof, refutation, peroration); style is the choice of words, figures, and register; memory is the disciplined recall of the composed speech; delivery is voice, pace, expression, and gesture.
Why it matters
How it works
A practical use of the canons is as a sequential audit. Did I find the strongest available arguments and appeals? (invention). Did I order them so each clears the way for the next? (arrangement). Have I chosen words and figures that fit the audience and occasion? (style). Can I deliver this without reading verbatim? (memory). Will my voice, pace, and presence carry the substance? (delivery). A speech that scores high on three canons and fails on the other two will still fail overall — which is why the framework persists.
The 18th-century British elocutionists revived the fifth canon as a discipline of its own. The 20th-century new rhetoric of Perelman and others gave fresh attention to invention. The canons are flexible scaffolding, not a rigid sequence — which is why they still serve.