People learn by failing. Yet when people associate failing and education, they tend to remember the agony of bad grades in school or being embarrassed in front of their schoolmates rather than the thrill of learning. Failure can certainly be agonizing. It might even be catastrophic. Most failures, however, aren't catastrophic; they are merely "expectation failures." That is, when you expect one thing and something different occurs. It is easy to see how such expectation failures lead to learning.
Consider a teenager's experiences with the opposite sex. When a boy takes a date to the circus and they have an especially fun time, he'll generalize from that experience. He may try going to the circus again when he wants to have an especially fun time with a different date. If it does not work out, the boy will think about why and modify his behavior in an attempt to do better next time. Generalizations provide expectations and when those expectations fail (in this case, when the second date falls flat), it signals an opportunity to learn. As children become adults, they form mini-theories of the opposite sex by building such generalizations and repairing them when they don't work.
This is the understanding cycle at work. We label our experiences with respect to their outcomes. When the outcome matches our expectations, we don't learn a great deal; we just continue the same behaviors or actions. When the outcome fails to match our expectations, we need to recover from the failure so as not to repeat the same behavior next time. Thus, we can learn a lot by failing.
Even what we typically call "success" often involves expectation failure. For instance, you may not particularly like squid. However, it may be that you go to a restaurant where you are served squid you really enjoy. While you would label this meal a success, your expectation about squid actually failed and you learned something as a result.
You might not only learn that you like squid, you now might want to try other foods that you had previously avoided. In situations like this when we recall experiences and use them as a guide to future behavior, we are using case-based reasoning. Case-based reasoning is the predominant way in which people think about their worlds. In deciding what to do in a given situation, we rely upon our memories of the most similar experiences we've had, and use them as a guide. Because this type of reasoning is so fundamental, it makes sense that we should tailor teaching to it.
Experts Teaching from Cases
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