When students challenge the relevance of their lessons, Bryan Caplan explains (in The Case Against Education), teachers often reply, “I teach you how to think, not what to think”:
Educational psychologists who specialize in “transfer of learning” have measured the hidden intellectual benefits of education for over a century. Their chief discovery: education is narrow. As a rule, students learn only the material you specifically teach them…if you’re lucky. In the words of educational psychologists Perkins and Salomon, “Besides just plain forgetting, people commonly fail to marshal what they know effectively in situations outside the classroom or in other classes in different disciplines. The bridge from school to beyond or from this subject to that other is a bridge too far.”
Many experiments study transfer of learning under seemingly ideal conditions. Researchers teach subjects how to answer Question A. Then they immediately ask their subjects Question B, which can be handily solved using the same approach as Question A. Unless A and B look alike on the surface, or subjects get a heavy-handed hint to apply the same approach, learning how to solve Question A rarely helps subjects answer Question B.
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One classic experiment teaches subjects how to solve a military puzzle, then tests whether subjects apply what they learned to solve a medical puzzle.
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Since subjects hear these two stories back to back, you might think almost everyone would leap to the convergence solution for the medical problem. They don’t. A typical success rate is 30%. Since about 10% of subjects who don’t hear the military problem offer the convergence solution, only one in five subjects transferred what they learned. To reach a high (roughly 75%) success rate, you need to teach subjects the first story, then bluntly tell them to use the first story to solve the second.
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Under less promising conditions, transfer is predictably even worse. Making the surface features of A and B less similar impedes transfer. Adding a time delay between teaching A and testing B impedes transfer. Teaching A, then teaching an irrelevant distracter problem, then testing B, impedes transfer. Teaching A in a classroom, then testing B in the real world impedes transfer. Having one person teach A and another person test B impedes transfer.
To apply schoolwork in the real world, you must normally overcome each and every one of these hurdles. You must see through surface features to underlying structure. You must select the few relevant lessons, and ignore the rest. You must remember relevant lessons years or decades after encountering them. You must apply what you learned in a nonacademic location, without your original teacher (or any teacher!) to hold your hand.
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The measured effect of education on informal reasoning, though positive, was tiny. Fourth-year high school students were slightly better than first-year high school students. Fourth-year college students were no better than first-year college students. Fourth-year graduate students were barely better than first-year graduate students.
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Respondents with more educational credentials definitely get higher scores. The point is that students barely improve between their first and fourth years of study. While people with better reasoning skills do complete more education, their reasoning skills are better at the outset. If education seriously showed students “how to think,” three additional years of study would sharply amplify their initial advantage. Yet students’ scores barely budge.
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By and large, college science teaches students what to think about topics on the syllabus, not how to think about the world.
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Each major sharply improved on precisely one subtest. Social science and psychology majors became much better at statistical reasoning—the ability to apply “the law of large numbers and the regression or base rate principles” to both “scientific and everyday-life contexts.” Natural science and humanities majors became much better at conditional reasoning—the ability to correctly analyze “if…then” and “if and only if” problems.
On remaining subtests, however, gains after three and half years of college were modest or nonexistent. Social scientists’ verbal and conditional reasoning scores slightly fell. Psychologists’ verbal scores slightly rose, but their conditional reasoning failed to improve. Natural science and humanities majors gained slightly in verbal reasoning, and modestly in statistical reasoning.
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Students primarily improve in the very tasks they study and practice. Even this isn’t guaranteed; humanities majors’ verbal reasoning barely budged.
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No one, not even law students, improved much in verbal reasoning. Chemists’ scores on all three subtests stayed about the same. But medical and especially psychology students improved in statistical reasoning, and law, medical, and psychology students all improved in conditional reasoning.
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Transfer researchers usually begin their careers as idealists. Before studying educational psychology, they take their power to “teach students how to think” for granted. When they discover the professional consensus against transfer, they think they can overturn it. Eventually, though, young researchers grow sadder and wiser. The scientific evidence wears them down—and their firsthand experience as educators finishes the job.