Proof in Rhetoric

Glossary of Grammatical and Rhetorical Terms

"Someone walked on the snow. The footprints are the proof.".

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In rhetoric, proof is the part of a speech or written composition that sets out the arguments in support of a thesis. Also known as confirmation, confirmatio, pistis, and probatio.

In classical rhetoric, the three modes of rhetorical (or artistic) proof are ethos, pathos, and logos. At the heart of Aristotle's theory of logical proof is the rhetorical syllogism or enthymeme.

For manuscript proof, see proof (editing)


From the Latin, "prove"

Examples and Observations

  • "In rhetoric, a proof is never absolute, since rhetoric is concerned with probable truth and its communication. . . . The fact is that we live much of our lives in the realm of the probabilities. Our important decisions, both at the national level and at the professional and personal level, are, in fact, based on probabilities. Such decisions are within the realm of rhetoric."
    - W. B. Horner, Rhetoric in the Classical Tradition. St. Martin's Press, 1988
  • "If we regard confirmation or proof as the designation of that part where we get down to the main business of our discourse, this term can be extended to cover expository as well as argumentative prose. . . .
    "As a general rule, in presenting our own arguments we should not descend from our strongest arguments to our weakest. . . . We want to leave our strongest argument ringing in the memory of our audience; hence we usually place it in the emphatic final position."
    - E. Corbett, Classical Rhetoric for the Modern Student. Oxford University Press, 1999

Proofs in Aristotle's Rhetoric
"The opening [of Aristotle's Rhetoric] defines rhetoric as the 'counterpart of dialectic,' which seeks not to persuade but to find the appropriate means of persuasion in any given situation (1.1.1-4 and 1.2.1). These means are to be found in various kinds of proof or conviction (pistis). . . . Proofs are of two kinds: inartistic (not involving rhetorical art—e.g., in forensic [judicial] rhetoric: laws, witnesses, contracts, torture, and oaths) and artificial [artistic] (involving the art of rhetoric)."
- P. Rollinson, A Guide to Classical Rhetoric. Summertown, 1998

Quintilian on the Arrangement of a Speech

"[W]ith regard to the divisions which I have made, it is not to be understood that that which is to be delivered first is necessary to be contemplated first; for we ought to consider, before everything else, of what nature the cause is; what is the question in it; what may profit or injure it; next, what is to be maintained or refuted; and then, how the statement of facts should be made. For the statement is preparatory to proof, and cannot be made to advantage, unless it is first settled what it ought to promise as to proof. Last of all, it is to be considered how the judge is to be conciliated; for, until all the bearings of the cause be ascertained, we cannot know what sort of feeling it is proper to excite in the judge, whether inclined to severity or gentleness, to violence or laxity, to inflexibility or mercy."
- Quintilian, Institutes of Oratory, 95 AD

Intrinsic and Extrinsic Proofs

"Aristotle counseled the Greeks in his Treatise on Rhetoric that the means of persuasion must include both intrinsic and extrinsic proofs.
"By extrinsic proof Aristotle meant direct evidence that was not the creation of the speaker's art. Direct evidence could include laws, contracts, and oaths, as well as the testimony of witnesses. In the legal proceedings of Aristotle's time, this kind of evidence was usually obtained in advance, recorded, put in sealed urns, and read in court.

"Intrinsic proof was that created by the art of the orator. Aristotle distinguished three kinds of intrinsic proof:

(1) originating in the character of the speaker;

(2) resident in the mind of the audience; and

(3) inherent in the form and phrase of the speech itself. Rhetoric is a form of persuasion that is to be approached from these three directions and in that order."

- Ronald C. White, Lincoln's Greatest Speech: The Second Inaugural. Simon & Schuster, 2002

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Your Citation
Nordquist, Richard. "Proof in Rhetoric." ThoughtCo, Apr. 5, 2023, Nordquist, Richard. (2023, April 5). Proof in Rhetoric. Retrieved from Nordquist, Richard. "Proof in Rhetoric." ThoughtCo. (accessed June 5, 2023).