Thinking Critically about Teaching Critical Thinking

A friend recently referred me to this online article (at bigthink.com) about this research study: the eye-catching phrase in both headlines being “Teaching Critical Thinking.”

(The online article is even more emphatic: “Study: There Are Instructions for Teaching Critical Thinking.”)

This headline sounds like great news. We can do it! Just follow the instructions!

We should, of course, be delighted to learn that we can teach critical thinking. So often, especially in upper grades, schools emphasize teaching “not what to think, but how to think.”

Every time we say that, we are—in effect—claiming to be teaching critical thinking.

The author of the BigThink article summarizes the societal importance of critical thinking this way:

We live in an age with unprecedented access to information. Whether you are contributing to an entry on Wikipedia or reading a meme that has no sources cited (do they ever?), your ability to comprehend what you are reading and weigh it is a constant and consistent need. That is why it is so imperative that we have sharp critical-thinking skills.

Clearly, students need such skills. Clearly we should teach them.

It Can Be Taught!

The study itself, authored by N. G. Holmes and published in the Proceedings of the National Academy of Arts and Sciences, follows students in a college physics course. The course explicitly introduced its students to a process for thinking critically about scientific data; it emphasized the importance of this process by grading students on their early attempts to use it.

For example (this excerpt, although complex, is worth reading closely):

“students were shown weighted χ2 calculations for least squares fitting of data to models and then were given a decision tree for interpreting the outcome. If students obtain a low χ2, they would decide whether it means their data are in good agreement with the model or whether it means they have overestimated their uncertainties.”

Early in the course, the instructors often reminded the students to use this process. By term’s end, however, those instructions had been faded, so the students who continued to use it did so on their own.

The results?

Many students who had been taught this analytical process continued to use it. In fact, many of them continued to use it the following year in another course taught by a different professor.

In other words: they had been taught critical thinking skills, and they learned critical thinking skills.

Success!

It Can Be Taught?

Sadly, this exciting news looks less and less promising the more we consider it.

In the first place, despite the title of his article, Holmes doesn’t even claim to be teaching critical thinking. He claims to be teaching “quantitative critical thinking,” or the ability “to think critically about scientific data and models [my emphasis].”

Doubtless our students need this valuable subset of critical thinking skills. And yet, our students think about many topics that defy easy quantification.

If we want our students to think critically about a Phillis Wheatley poem, or about the development of the Silk Road, or about the use of gerundives, we will quickly recognize they need a meaningfully different set of critical thinking skills.

How, for example, would a student use “weighted χ2 calculations for least squares fitting of data” to compare the Articles of Confederation with the Constitution of the United States?

To return to the examples offered in BigThink’s enthusiastic paragraph: despite this author’s enthusiasm, it’s not at all certain this procedure for analyzing “scientific data and models” will help us update a Wikipedia entry, or critique an unsourced meme.

(It might, but—unless we’re editing a very particular kind of Wikipedia entry, or reading a very statistical meme—it probably won’t.)

In brief: ironically, the headlines implying that we can “teach critical thinking” generally do not stand up to critical thought.

The Bigger Picture

Cognitive scientists, in fact, regularly doubt the possibility of teaching a general set of critical thinking skills. And here’s one big reason why:

Different disciplines require different kinds of critical thought.

Critical thinking in evolutionary biology requires different skills than critical thinking in comparative theology.

The field I’m in uses psychology and neuroscience research to inform teaching; hard experience has taught me that the fields of psychology and neuroscience demand very different critical thinking skills from their practitioners.

Perhaps your own teaching experience reveals the same pattern:

The English department where I taught included some of the sharpest minds I know: people who can parse a sonnet or map a literary genre with giddy dexterity. Their critical thinking skills in the world of English literature can’t be questioned.

And yet, many of these same people have told me quite emphatically that they are hopeless at, say, math. Or, chemistry. Or, doing their taxes. Being good critical thinkers in one discipline has not made them successful at critical thought in others.

Chapter 2 of Daniel Willingham’s Why Don’t Students Like School explores this argument at greater length.

The Smaller Picture

There’s a second reason that it’s hard to teach general critical thinking skills: knowledge of details.

To think critically about any topic, we need to know a very substantial amount of discipline-specific factual information. Finding those facts on the interwebs isn’t enough; we need to know them cold—have them comfortably housed in long-term memory.

For example: to use Holmes’s critical thinking technique, you would need to know what “weighted χ2 calculations for least squares fitting of data” actually are.

Even more: you’d need to know how to calculate them.

If you don’t have that very specific kind of detailed knowledge, you’re just out of luck. You can’t think critically in his world.

Another example. Much chess expertise comes from playing lots and lots of chess. As Chase and Simon’s famous study has shown, chess experts literally see chess boards differently than do chess novices.

You really can’t think like a chess expert (that is, you can’t engage in critical chess thinking) until you can see like a chess expert; and, seeing like a chess expert takes years. You need to accumulate substantial amounts of specific information—the Loomis gambit, the Concord defense—to make sense of the chessboard world.

Your own teaching experience almost certainly underlines this conclusion. Let me explain:

How often does it happen that someone learns you’re a teacher, and promptly offers you some heartfelt advice on teaching your students more effectively? (“I saw this AMAZING video on Facebook about the most INSPIRING teacher…”) How often is that advice, in fact, even remotely useful?

And yet, here’s the surprise: the person offering you this well-meaning advice is almost certainly an expect in her field. She’s an accomplished doctor, or financial adviser, or geologist, or jurist. In her field, she could out-critical-think you with most of her prefrontal cortex tied behind her occipital lobe.

Unfortunately, her critical thinking skills in that field don’t transfer to our field, because critical thinking in our field requires a vast amount of very specific teaching knowledge.

(By the way: twice now this post has assumed you’re a teacher. If you’re not, insert the name of your profession or expertise in the place of “teacher.” The point will almost certainly hold.)

Wishing and Thinking, not Wishful Thinking

As so often happens, I feel a bit like a grinch as I write this article. Once again, I find myself reading news I ought to find so very exciting, and instead finding it unsupported by research.

Truthfully, I wish we could teach critical thinking skills in general. If you’ve got a system for doing so, I genuinely hope you’ll let me know. (Inbox me: [email protected])

Even better: if you’ve got research that shows it works, I’ll dance a jig through Somerville.

But the goal of this organization—and the goal of Mind, Brain, and Education—is to improve psychology, neuroscience, and pedagogy by having these disciplines talk with each other deeply and knowledgeably.

And with that deep knowledge—with critical thinking skills honed by scientific research—we know that critical thinking skills must be taught discipline by discipline; and, they must be honed through extensive and specific practice.

This task might sound less grand than “teaching critical thinking skills.” And yet, by focusing not on lofty impossibilities, but on very realistic goals, we can indeed accomplish them—one discipline at a time.