When it comes to rhetoric, Plato was right and Aristotle — not so much.

Distilled, Aristotle thought rhetoric good for democracy, though his definition of “by the people” was closer to our Founding Fathers’ intent of only certain people than to today’s more-the-merrier model. Given this assumption of a narrow, educated, self-governing populace, Aristotle likely envisioned that those practicing rhetoric would be guided by accepted rules of argument and engagement, emphasizing ethos (trust and credibility), pathos (appropriate use of emotion) and logos (logical argument and facts).

Plato, who was Aristotle’s mentor, thought otherwise — that rhetoric, or the art of persuasion, in the wrong hands was dangerous and likely to be abused to appeal to people’s base motives. He foresaw the unethical, dishonest uses that a skilled but immoral speaker could put his persuasive powers to, with credulous people eager to believe or buy whatever he was selling.

Which brings us unavoidably to Donald Trump, as if you hadn’t guessed.

Donald Trump said after the April 26 primaries that he sees no reason to change his personality, despite receiving criticism for not "acting presidential." (Peter Stevenson/The Washington Post)

We at least owe Trump thanks for bringing these two ancient philosophers out of history’s woodwork and back into the conversation. Trump also has inspired reconsideration of rhetoric’s rightful place in the classroom, where it was once considered an essential component of “a gentleman’s” education.

One such classroom can be found at the University of Virginia School of Law, where I was recently a guest lecturer. What better time to be reviewing rhetoric’s ancient rules and modern applications than during a presidential election that features one of the most blazing examples of unsavory rhetoric since Clark Stanley boiled a live rattlesnake at the 1893 World’s Fair in Chicago?

It turned out that “Stanley’s Snake Oil” had nary a drop of reptile adipose but was instead a mixture of beef fat, red pepper and turpentine. Even if it had contained l’huile de serpent, the liniment would have been ineffective as a curative. Rattlesnake oil contains only a third of the vital acid found in the widely popular Chinese snake oil of the time, which was made from water snakes. Thought you’d like to know.

So, the question for today’s class: Is Trump the huckster that Plato predicted would someday organize an angry mob into a proud army of anti-intellectual patriots inoculated to facts and reason?

Why, yes! But don’t take my word for it. Consider instead the appraisal of U-Va. law professor Robert Sayler, who has co-written a book with Molly Bishop Shadel, “Tongue-Tied America,” as a template for would-be high school rhetoric teachers. Using Aristotle’s aforementioned framework, Sayler divined the Greek philosopher’s answer to the question: “Trump’s buffoonery and unhinged chatter reduces to utter catastrophe.”

Let us count the ways.

First, in the matter of ethos, or earning the trust of one’s audience, Trump is as big a prevaricator as he accuses “Lyin’ Ted” Cruz of being. PolitiFact gave Trump its 2015 award for the most fibs. In distrust do us part.

Second is pathos, which Sayler defines as the sparing appeal to emotions. For The Donald, another “F.” Says Sayler: “Trump routinely rages, flush-faced, anger-spewing, sputtering, especially when challenged.” He has spoken of people leaving his rallies “on stretchers” or deserving a “punch . . . in the face,” while promising to pay assailants’ legal fees.

Third and last, Trump also flunks logos. Channeling Aristotle, Sayler opines that Trump’s logic, common sense and factual argumentation are “a minefield of chaos.” Rather than advance positive proposals, Trump spends most of his time railing against what he opposes: the Geneva Conventions, NATO, world trade, the United Nations, the president, “experts” and, of course, “the establishment.”

Otherwise, he operates in a substance-free zone of narcissistic fantasy. “They love me,” he insists. “I could stand in the middle of Fifth Avenue and shoot somebody, and I wouldn’t lose any voters.”

Sayler describes several of Trump’s other anti-logos traits, with amusing categories such as “The Bonkers,” which covers the mogul’s remark about Hillary Clinton’s “disgusting” bathroom break. Under “The Frightening,” Sayler points to Trump’s wish to be “unpredictable,” including firing off possible nuclear attacks. Trump, concludes the professor, is a world-class demagogue and blunderbuss.

It’s little wonder that the “Stop Trump” movement has gained traction, leading recently to an obstructionist partnership between Cruz and John Kasich. It is also highly unlikely that Trump supporters give a hoot. Plato, Aristotle and Sayler are all elitists, aren’t they? But what should be plain to everyone else is that the study of rhetoric is essential to an educated populace, lest rising generations fall prey to future demagogues and the perilous fates that await the unwitting.

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