A former partner at McKinsey & Company, Bouygues has helped transform more than 25 firms. Over the course of a twenty-year career, she has raised hundreds of millions of dollars in capital, renegotiated billions of dollars in debt, and brought dozens of companies into the black.
Consider the following problem:
“A treasure hunter is going to explore a cave up on a hill near a beach. He suspected there might be many paths inside the cave so he was afraid he might get lost. Obviously, he did not have a map of the cave; all he had with him were some common items such as a flashlight and a bag. What could he do to make sure he did not get lost trying to get back out of
the cave later?”
The question, many will notice, bears a striking resemblance to the story of Hansel and Gretel. And the solution is basically the same: put some sand from the beach in the bag and leave a trail, just as Hansel and Gretel left a trail of breadcrumbs to the witch’s house.
The example comes from an article by cognitive scientist Daniel Willingham about how to teach critical thinking (1). The study he describes (2) illustrates two things about critical thinking: the need for robust background knowledge and the importance of deep structure. A study showed that American students, who are generally familiar with the Hansel and Gretel story, were more likely to solve the problem than students from other cultures, who hadn’t been exposed to the story. “The deep structure of the problem is so well represented in their [American
students’] memory,” Willingham writes, “that they immediately saw that structure when they read the problem.”
Teaching background knowledge is relatively straightforward with the right level of material and good teaching. But how do educators teach the habits of mind that involve being active and creative in the analysis and application of background knowledge as students are acquiring that knowledge?
Before trying to answer that question, let’s step back for a second. What exactly is critical thinking? The question itself is a little misleading. It’s an error to think of it as a single content area like Russian history or chemistry. Although there’s overlap between different types of critical thinking, thinking like a good scientist involves a different set of skills than thinking like a good literary critic or historian. Critical thinking is domain-specific, and determining exactly what those skills are takes time and investigation (3).
That might make it seem like it’s impossible to teach — or that teaching it would be no different than teaching the domain itself. But critical thinking skills do not come along “for free” with good domain instruction: explicit critical thinking instruction is needed.
Moreover, while critical thinking is domain-specific, there are certain broader modes of thinking and dispositions — taking steps to identify and remediate bias, considering alternative points of view, applying the principle of charity, for example — that cut across domains. Being able to apply those skills widely is not just incidental to critical thinking; it’s arguably at the core of critical thinking. Critical thinking skills, if acquired, should help students succeed in many
different domains, from their careers to their personal lives to their civic contributions.
Research has shown that the best way to teach these skills is through what’s sometimes called “direct infusion” (4). This means neither teaching critical thinking in the abstract, nor expecting students to acquire critical thinking skills “for free.” Rather, explicit critical thinking instruction is incorporated into subject-matter instruction, leading to gains in critical thinking without sacrificing domain knowledge acquisition (5).
For example, a recent study divided similar groups of college students studying psychology into three groups: one receiving supplementary direct-infusion critical thinking instruction, one receiving only subject-matter instruction, and another receiving subject-matter instruction supplemented by memory improvement skills (6). All the groups of students studied from the same textbook. The critical thinking-infused group received explicit instruction, exercises, and feedback on arguments analysis and scientific method in cognitive psychology, as well as practice in evaluating evidence and critical reading. This group performed significantly better on tests of argument analysis and critical reading. These students also showed gains in “metacognitive monitoring”; that is, they were more accurately able to understand and evaluate their own thinking as well, a key part of critical thinking.
The principle behind direct infusion, bluntly put, is to go deeper. Students don’t just study the material directly; they study the principles behind the material: in this case the methods used in cognitive science and the form of the argument put forward in the field. This goes for K-12 classes just as much as college. My foundation, Reboot, recently put out a teachers’ guide to critical thinking, including ideas for deeper thinking throughout the curriculum. Depending on the field, there are many different ways deeper, structural thinking can be encouraged and different tools teachers might use. For example, in argument-heavy fields like law or argumentative writing, argument-mapping software has shown positive effects in helping students visualize the way evidence supports claims (7). The key is making structure explicit and visible within the context of subject-matter instruction and giving students practice applying the insights into deep
structure. It’s crucial to give teachers the training and support to use these tools and to prioritize depth-structure learning within the subject-matter instruction they’re already doing.
Recognizing the depth-structure of the field you’re studying is all well and good, but one thorny problem remains: transfer. How do this recognition of depth and domain-specific critical thinking skills get successfully transferred to new problem types and domains? Again, educators have too often thought that this skill comes for free. Research suggests that this kind of “spontaneous transfer” is not typical (8). As with direct infusion itself, it’s crucial for teachers to be explicit here (9). They must teach for transfer.
This need not be burdensome and can even help enliven instruction. Jonathan Haber, for example, suggests that upon teaching the principles of proofs in geometry, math teachers invite students to explicitly reflect on the premise-conclusion form of argument more generally (10).
They could even spend time applying this form to problems outside the domain of geometrical reasoning. Another promising technique involves “problem comparison”: teaching problems with very different surface structures, but the same depth structure (11) (12).
In this way, teaching for transfer means going yet deeper, not just to the philosophical underpinnings and methods of the subject being taught, but to the principles of human knowledge more generally. When students jump from the deep-structure of one discipline to that of another, they are reminded that the barriers between different domains of human knowledge that disciplines put up are somewhat artificial. This can help encourage interdisciplinarity as well as metacognitive reflection on the kinds of thinking students are doing in different disciplines.
This also suggests a place for more general critical thinking courses like philosophy. Such courses, or units within other courses, can be a space for more general reflection on commonalities between different types of domain-specific critical thinking. One study has shown
philosophical dialogue programs for elementary-schools students can lead to gains in math and science (13). This suggests that reflection on general principles of thinking can be productively combined with domain-specific critical thinking instruction, especially if explicit connections are drawn by teachers between these different learning activities.
Establishing these kinds of pathways toward depth structure within and between domains is a promising method for teaching kids the critical thinking skills they need, especially as they navigate an increasing complex media environment and job market. Educators and policymakers should prioritize teaching below the surface level.