The epideictic oratory, also called ceremonial oratory, or praise-and-blame rhetoric, is one of the three branches, or "species" (eidē), of rhetoric as outlined in Aristotle's Rhetoric, to be used to praise or blame during ceremonies.
The term's root has to do with display or show (deixis). It is a literary or rhetorical term from the Greek ἐπιδεικτικός "for show". It is generally pronounced ɛpᵻˈdaɪktɪk or ɛpᵻˈdeɪktɪk. Another English form, now less common, is epidictic ɛpᵻˈdɪktɪk.
This is rhetoric of ceremony, commemoration, declamation, demonstration, on the one hand, and of play, entertainment and display, including self-display. It is also the rhetoric used at festivals, the Olympic games, state visits and other formal events like the opening and closing ceremonies, and celebrations of anniversaries of important events, including illustrious victories, births, deaths, and weddings. Its major subject is praise and blame, according to Aristotle in the limited space he provides for it in the Art of Rhetoric (Freese translation).
This rhetoric deals with goodness, excellence, nobility, shame, honor, dishonor, beauty, and matters of virtue and vice. The virtues or the "components" of virtue according to Aristotle, were "justice, courage, self-control, magnificence, magnanimity, liberality, gentleness, practical and speculative wisdom" or "reason". Vice was the "contrary" of virtue.
In his book Rhetoric and Poetics in Antiquity, Jeffrey Walker claims that epideictic rhetoric predates the rhetoric of courts and politics, the study of which began in the 5th or 4th century BC with the Sophists. The other two kinds of public speech were deliberative or political speech, and forensic, judicial, or legal speech. Epideictic rhetoric or style is according to Aristotle most appropriate for material that is written or read. In the Art of Rhetoric, Aristotle stated that "The epideictic style is especially suited to written compositions; for its function is reading." (Book III, 12).