Chapter 5 — Avoid Illusions of Knowing
We are all susceptible to illusions that can cloud our judgment of what we know and don’t know. For example, reading a text repeatedly creates fluency with the writing that Catherine Johnson, a Minneapolis cop, recounts how officers trained themselves to seize a gun at close quarters by practicing their technique on a fellow officer, breaking his grip, taking the gun, and returning it to repeat the maneuver. They were confident in their mastery until the night when a cop on a call took the gun from an assailant and then handed it right back again. is often mistaken for mastery of content: the re-reader develops an “illusion of knowing” based on familiarity of the content but struggles later at test time when asked to explain the underlying concepts. Learners need tools to keep their judgments of knowing aligned with reality. Chief among these is testing in all its varied forms, from classroom quizzing to self-administered flashcards. Testing both strengthens learning and shows where improvement is needed.