Well-meaning Lies for Teaching


I remember our high school math teacher lying to the class while teaching. What a brilliant pedagogical idea!

He would spend dozens of minutes explaining a concept while we were all concentrated and silent. Once he was finished and we were confident that we had understood, he would confess to us that he was lying. He would go back to the beginning of the explanations to show the naivety of the whole exercise. Why do I find such a brilliant pedagogy?

Firstly because it takes into account the fact that things are more complicated than you think. Not everything can be understood by the learner in one step. In fact, there are concepts that:

  1. can be understood without help
  2. can be understood with help
  3. cannot be understood even with help

This idea is mainly inspired by the zone of proximal development introduced, but not fully developed, by psychologist Lev Vygotsky:

The zone of proximal development is an area of learning that occurs when a person is assisted by a teacher or peer with a higher skill set. The person learning the skill set cannot complete it without the assistance of the teacher or peer. The teacher then helps the student attain the skill the student is trying to master, until the teacher is no longer needed for that task. - Wikipedia

Example: First you learn that the numbers start at zero. Once you have experimented with this concept, you can go further and see that this assumption was naive since negative numbers also exist.

A second reason to lie when teaching is that the learner cannot see the implications of being right the first time. I’ve already taken an example in the Emancipation Trend article about the embarrassing situation of realizing someone is right for the wrong reasons.

We must first wrongly understand, realize it, understand why, and move forward. Moving directly to the final stage of the answer will not help you understand any nuance of it. In other words, you have to face the limitations of the model to refine it. The idea was well articulated by Brian Redman in the “Effective Troubleshooting” chapter of the SRE book:

Be warned that being an expert is more than understanding how a system is supposed to work. Expertise is gained by investigating why a system doesn’t work. - Site Reliability Engineering: How Google Runs Production Systems

This pattern is quite similar to that which claims that immediate success is the enemy of learning. Learning how we succeeded (or failed) is much more sustainable than the success itself.

In summary, the benefits of well-meaning lies for teaching:

  1. Concepts can be addressed step-by-step by momentarily eliminating parts that are outside the zone of proximal development.
  2. Realizing that you have understood a concept the wrong way gives you a much deeper level of understanding than if you had got it right the first time.