The Illusion of Explanatory Depth
Asked to write out how a zipper works step by step, people's rating of their own understanding fell by a fifth. The same gap sits under most plans that reach your desk, and one question exposes it.
Ask people how well they understand a zipper and they'll rate themselves fairly high. Ask them to explain it step by step, and the illusion of explanatory depth gives way.
Leonid Rozenblit and Frank Keil ran exactly this at Yale in 2002, with zippers, flush toilets and cylinder locks. After writing out how each one works, students' ratings of their own understanding fell by about a fifth. After a harder follow-up ("how would you pick this lock?"), they fell further.
In 2013, Philip Fernbach and colleagues found the same drop with policies like cap-and-trade, plus a telling contrast. Listing reasons for a view left confidence intact. Explaining the mechanism deflated it. Reasons are easy to produce. A causal chain exposes every missing link.
(One caveat: Fernbach's further finding, that explaining moderated political views, failed to replicate. The drop in confidence held up.)
Most plans that reach your desk come with reasons. Few come with the chain.
The nudge: Before approving the next plan, ask: "Walk me through how this gets us there, step by step." Listen for the step where the pace quickens. That's the gap to fix.
Source: Rozenblit & Keil, The misunderstood limits of folk science: An illusion of explanatory depth, Cognitive Science (2002); Fernbach, Rogers, Fox & Sloman, Political extremism is supported by an illusion of understanding, Psychological Science (2013); Crawford & Ruscio, Asking people to explain complex policies does not increase political moderation, Psychological Science (2021)
