In my first or second year of high school teaching — my memory is hazy on timing — I had an exceptional sophomore named Anna. Anna was a political radical, or so she said. She was an articulate critic and, for an unskilled teacher, kind of a pain. She wasn’t loud or disruptive, but she was better read than all of my other students, and talked past most of them. I was a lousy translator.

I did better with her one on one. Anna was keenly interested in Latin America. She told me that she wanted to write her research paper on the Cuban Revolution of 1959. Anna was going to explain why the Cubans revolted, she said. I asked her what her hunch was, her working hypothesis. She said that the Cubans revolted because they were poor and oppressed.

I didn’t know much about managing a heterogeneous group of 10th graders, but I’d just spent close to two decades working alongside political scientists. I’d absorbed from them a very unhealthy skepticism about narrative and storytelling, and a remarkably salutary skepticism about argument. Anna’s was a classic bad argument.

So I asked Anna, what proportion of Latin Americans, in her estimation, were poor and oppressed? Quite a few, she thought. And how many of those poor-and-oppressed Latin Americans actually staged revolutions? Anna got her thinking face on. She sat for a minute, and then said she’d work on it.

During my next one-on-one meeting with Anna, she reported that she’d changed her focus. She was now going to explain why Costa Rica had the best functioning democracy in Central America. She had gotten to this topic by reading more about Cuba, trying to figure out what made Cuba in the ‘50s different from other Latin American countries. Over and over, the sources she was reading kept telling her that Costa Rica was also an outlier. Now that she was on the trail of what, many years later, Jon and I would call Question Three, she wanted to pursue it to a satisfactory conclusion.

Anna was bright and diligent, but more important, she had an intellectual conscience. She discovered something that upset her, and pursued that discovery anyway. Costa Rica, she informed me, was the most ethnically homogeneous country in Central America. It had a vanishingly small indigenous population, unusual for the region. Costa Rica’s indigenous population had been exterminated or driven out. The result, Anna reluctantly concluded, was that it was easier to establish stable electoral institutions.

She was more diligent than I am. I never read enough to know whether her findings were robust or original. The paper was terrific, as I recall, though I no longer have a copy. At any rate, I did learn a ton from Anna. I learned, among other things, that the logic of comparative explanation — Question Three — is neither intuitive nor obvious, even to the very brightest students, or teachers.

Question Three Has No Verbs

You’ll notice that our current Question Three has the oddest syntax of all four questions. It’s the only one of the four that lacks a verb. The original and now-obsolete version of Question Three was, “Why did that happen?,” followed briefly by, “Why did that really happen?” Neither version gave adequate guidance. For people new to thinking like social scientists, the bland “Why did that happen?” didn’t remind them to avoid the trap that Anna first fell into. They thought that describing what people were thinking — that they were being treated unjustly, in the Cubans’ case — was the same as explaining what they did.

The current version of the question, Why then and there? — a brilliant suggestion from a colleague who once heard us muddle through a Question Three workshop — focuses attention on what your brain has to do when it wrestles with a puzzle about the conditions that make the patterns of events around us move and change. It’s worth sacrificing a verb to be reminded that, without comparison, you’re just not explaining things. We’ve even got our own mnemonic now, a chorus worth repeating whenever you ask Question Three: “Explain a change with a change and a difference with a difference.” And, for good measure: “Factors, not actors!”

Now that I know that I have to teach Question Three explicitly, and now that I’ve got some techniques for doing so, I don’t have to rely upon geniuses like Anna showing up in my classes in order to get good results. In my current US History class, I 4QM the whole research process. Students tell stories first. They share answers to Question One about their topic with their classmates. Then I encourage them to find a Question Two puzzle to dig into. Pick an important or curious decision made by a person or group in their story. Then find the resources that would help them to say, convincingly, what they were thinking.

My more ambitious and capable students can pursue Question Three puzzles, but they know in advance that those are more challenging. Question Three requires disciplined thinking and comparative case studies (or a trove of quantitative data, if you can find it). And when I get an Anna, as I did last year, the results are now quite remarkable.

Rebecca was interested in Native America politics. Her research narrative was about the Navajo. She was impressed, during her initial research, by how comparatively well developed Navajo political institutions were. She wondered why. So she found out. Along the way, she learned a ton about the history of government relations with Native tribes and about the ecology and economics of reservations — including a surprising amount about sheep herding! The final paper laid out the factors that distinguished the paths of political development of the Navajo and Lakota Sioux, with frequent references to other tribes. The result explained, with impressive clarity and persuasiveness, why Navajo political institutions are so much more robust than those of other tribes.

With my encouragement, Rebecca sent the essay to one of the scholars whose work informed her own. He wrote back — five single-spaced pages — praising her work and engaging her in scholarly conversation about it.

That experience meant something to Rebecca. Next year, she is heading off to Oxford University to study with their Human Sciences faculty. In a note she wrote me to thank me for my letter of support, she mentioned her “passion for social science.” Anna had that passion, too. But I wasn’t clear enough at the time in my own practice to make that way of speaking available to her. Rebecca, on the other hand, knows how to describe her intellectual curiosity, and to pursue it systematically.

We sometimes say, about students like Anna and Rebecca, that they could learn under a rock. In some sense, that’s true. Both of them are way smarter than I am, for sure. It’s possible that most of the classes they attended in high school, mine included, could have been replaced by independent reading time and they’d have been no worse off. But if you’re willing to impose discipline and clarity on your classroom questioning — the difference, for me, between the Anna Era and the Rebecca Era — you might fight that even your smarty-pants students will learn to think with greater discipline and clarity about the human world. As I’m confident Rebecca will prove in the years to come, that’s good for all of us.