In the winter of 1571, on his thirty-eighth birthday, one of history’s most original minds retreated to his castle tower. Michel de Montaigne had been a successful diplomat and businessman. He owned a winery, Chateau d’Yquem, that still makes pricey Sauternes. Now, with his life more than half over, Montaigne sat alone with his fifteen hundred books and his cat and his dog and began a series of experiments called “assays” (essais in French). He was making a deliberate metallurgy pun; an assay finds the components and value of a metal. But the word also means “attempt.” Montaigne’s as- says were an experiment on himself. They mentally weighed, melted down, and assessed the value of his own life. No one had ever conducted this kind of experiment before; and because of his essais, the world has never been the same. Montaigne’s writings ushered in the age of the Enlightenment, helped the Christian world recover from bitter religious wars, and became a chief inspiration for Thomas Jefferson.

And so Montaigne invented the essay, a genre of literature that has tortured students for many generations. Reading this funny, bawdy, conversational, ingenious man for the first time feels like meeting the greatest uncle you could imagine. You almost expect him to gently lift his cat off the chair and offer you a seat. He pours you a glass of his sweet golden wine and then tells you about the time he talked his way out of being held hostage by a group of bandits. But most readers don’t realize that Montaigne was doing something even more powerful than in- venting a new way of writing. His essays comprise one of the most effective arguments in human history. In a world that was tearing itself apart with conflicting eternal truths, Montaigne argued for a humble, science-loving, tolerantly curious view of humanity. His famous motto should begin every book: Que sais-je, “But what do I know?”

At a time when angry tribes are forming around conflicting certainties, Montaigne’s kind of persuasion offers more than a great way to improve your writing game. It can help you feel better about yourself, and maybe heal a whole society. So let’s get to assaying life through our own essays. While other books will tell you all the technical ins and outs of essay writing, here we will focus on three persuasive tools: ethos, pathos, and logos. Sound familiar?

Once we go through the essay techniques of the Big Three tools, we’ll watch them come together in a single college admissions essay. It just happens to be one my son, George, wrote.

Ethos: Quirk It

The most persuasive kind of essay is the personal essay. Its seduction comes through the relation- ship it establishes with the audience. By getting your readers to like and trust you, you can get them to agree with your essay’s point—the moral of your story.

But despite what your essay reveals about you, no matter how many intimate details you share, the personal essay isn’t really about you. This is worth repeating, because it states the central mantra of rhetoric: even if it’s about you, it’s not about you.

When you put yourself on a page, you display an example of humanity. An essay works like a laboratory experiment. When I was taking high school biology, each of us students had to dissect a frog—a practice that most schools mercifully no longer require. The point wasn’t to learn about my particular frog; it was to learn about frogs. That one sacrificial victim was supposed to teach me what any frog might look like inside. (My own frog seemed to have come from outer space; none of its organs looked any- thing like the pictures in the textbook.)

Writing yourself into an essay creates a character much like a laboratory frog. When you reveal your greasy, imperfect innards, you offer a lesson in humanity. Montaigne certainly thought so. His assays into his life fol- lowed the theory that the more he examined himself, the more he would learn about people in general. And, because he published his essays, he was showing humanity to humanity itself. The beautiful thing about his approach was that he was writing at an especially inhumane time, when religious zealots throughout Europe were slaughtering each other. By making his essay about a likable and trustworthy character—himself—he showed his fellow humans that they weren’t such a bad breed after all. In the most persuasive way, Montaigne helped invent humanism, the belief that people could get together and improve society on their own.

How did he describe himself? With all his good points and bad. His not- so-flattering side forms the best parts of his essays. He cheerfully admits to being a lazy student. “If one book does not please me, I take another,” he says. He adds that he never reads at all “until I’m tired of doing nothing.” This is quite an admission for a man fluent in Latin.

Montaigne is using a tool I introduced in my book: the tactical flaw. You gain the audience’s sympathy through your own imperfection. In a speech, your own obvious nervousness can suffice for the flaw. A great way to reveal your flaw in an essay is to use self-deprecating humor; Montaigne’s most charming moments have to do with his own quirks. One culprit that keeps Montaigne from his studies is his dog. He writes that he is not afraid to confess “the tenderness of my nature so childish that I cannot well refuse to play with my dog” when it asks him, no matter how bad the creature’s timing.

But he doesn’t offer this confession just to seem like a regular person. He also shows how many traits he shares with other people. After talking about his dog in an essay titled “Of Cruelty,” he follows up with a list of the ways other cultures have coddled animals. The Turks have hospitals for beasts, he says. Roman citizens paid taxes to feed geese. The Athenians had a temple where mules got all the food they wanted. The ancient Egyptians gave animals decent burials and mourned their death. In other words, being an animal lover was nothing unique to Montaigne or his time. His flaw is our flaw. He’s like the comedian who jokes about all the failed diets she tried, getting a knowing laugh from all us failed dieters in the audience. We frogs have all the same innards.

It can be hard to talk about yourself in less than flattering terms, in a way that avoids hunblebragging. (“I’m such a geek I get straight A’s!”) But with telling detail and a generous sense of humor, you can pull off the biggest ethos trick of all, decorum. You make your audience think you are one of them. If the noble winemaker/diplomat Michel de Montaigne can do it, so can you.

Every month, I try to follow Montaigne’s lead in a regular three-hundred-word personal essay I write for a magazine. Each essay gently attempts to persuade the reader about something; I use the tactical flaw to sweeten the message. Though I’ve written more than 120 of these essays, I still find plenty of material, having no lack of flaws to draw upon.

Here’s one such essay I wrote about the importance of thanking the people around you. I could have sermonized: “The world would be a better place if we made an effort to say thanks to each other more often.” But where’s the ethos in that? Instead I describe myself (truthfully) as a thankless spouse trying to keep up with his better half. Note the details about dishes and laundry, a bone of contention in almost every marriage. By describing my flaws, I’m describing at least half of humanity.

Gratitude has been getting a lot of attention these days. Many people have come to consider it a form of self-help. Sure, counting your blessings does do you good. But my wife, Dorothy, takes gratitude to a new level. She uses it to manipulate her husband.

It started when she returned to a salaried career after 20 years of raising children. I was home writing a book (on persuasion, ironically) and began doing household chores. The first night she came home, Dorothy said, “Thanks for doing the laundry.”

It occurred to me that I had never thanked her for doing that. So I committed myself to the laundry operation.

Then there were the dishes. Personally I prefer letting them stack over a day or two, for efficiency’s sake. But knowing her strong preference for an empty sink, I bowed to her wish. She thanked me the first time, and so I became master of dishes.

I came to realize she had been thanking me all along: for read- ing to the children every night, for being kind to her relatives, for sometimes doing yard work. And every time she had thanked me for something, I did more of it.

Two can play at this game, I figured. I began thanking her for earning a paycheck, for cooking occasionally, for building a fire in the fireplace, for letting me buy the latest electronic gadget without her getting sarcastic.

It wasn’t exactly a gratitude arms race. I believe she was genu- inely grateful when she thanked me. For my part, as I tried to keep up with her, I began noticing more of the many things she does for me.

This spring we celebrate 35 years of marriage, and I find I can’t thank her enough.

A few pointers that I’ve picked up from writing essays like that:

Set your topic right off the bat.

Every essay explores a point. Your reader will get frustrated and leave you if she can’t figure out that point from the get- go. You especially need to introduce your approach in a short essay, which offers no room to mess around. Get your topic down in the first or second sentence.

Give your theme a twist.

Thankfulness is good. Uh-huh. Thanks for sharing; now go needlepoint it on an ugly pillow. Every essay, even the most political, humanity-is-in-peril essay, has to entertain. A boring point that people have heard since time immemorial may earn the praise of your mother, but you’ll lose your reader. My essay starts with the assertion that gratitude is a thing these days, but then it spins off into gratitude as a form of persuasion. (Having read this book so far, you may not be surprised by this veer into persuasion, but most other audiences won’t expect it.) My hope is that my reader will want to see how this whole cynical-thanks affair turns out.

Try an epiphany.

Instead of banging your point home, show yourself discovering it. Just as a TED talk employs inductive reasoning (see the third edition of my book), an effective essay can work the same way.

Show your flaws.

I failed to thank Dorothy, neglected to do the dishes promptly, and turned her gratitude into an arms race. But I hope the reader will see redemption in my discovering these flaws for myself and trying to improve.

Ideally, by the end of the essay the reader should conclude that if gratitude can help this jerk stay married, maybe the rest of us can, do. Persuasion accomplished.