A Two-Effects Model of Explanation on Exposing the Illusion of Understanding

Abstract

People often overestimate their understanding of how things work. For instance, people believe that they can explain even ordinary phenomena such as the operation of zippers and speedometers in greater depth than they really can. This is called the illusion of understanding (originally known as the illusion of explanatory depth). Fortunately, a person can expose the illusion by attempting to generate a causal explanation for how the phenomenon operates (e.g., how a zipper works). This might be because explanation makes salient the gaps in a person’s knowledge of that phenomenon. However, recent evidence suggests that people might be able to expose the illusion by instead explaining a different phenomenon. Across six preregistered experiments and one secondary data analysis, I examined whether explaining one phenomenon (e.g., how a zipper works) leads individuals to lower their self-assessed knowledge of unrelated phenomena (e.g., how snow forms). My findings demonstrated that participants consistently revised their understanding downwards, not only for the item they explained but also for other items they did not explain. For instance, participants reported reduced understanding of speedometers after explaining helicopters or zippers. Contrary to prior research, participants did exhibit the illusion for familiar movie plots (Experiment 4), but consistent with prior research, participants did not exhibit the illusion for common procedures (Experiment 5). Additionally, when common procedures were included in the experimental design used in Experiments 2 and 3, participants showed no illusion whatsoever (Experiment 6). Finally, an analysis of explanation quality using ChatGPT to code the explanations revealed that the reduction in perceived understanding after explaining (compared to before) correlated with the difference between how well the participant thought they understood the item and how well they actually explained it, but only for explained items. These findings challenge the common framework of how the illusion of understanding operates. Throughout the thesis I evaluate alternative models of the illusion and ultimately find the most support for a two-effects model of explanation, wherein failing to explain a phenomenon temporarily makes people recognize the gaps in their knowledge of the item they explained and makes them feel less knowledgeable about most other things.