Borrowed Knowledge Feels Like Our Own

One of the easiest ways to overestimate our understanding is to live inside a world built by other people’s knowledge.

I can use a phone without understanding radio communication, semiconductor design, battery chemistry, cryptography, networking, and operating systems. I can drive a car without being able to explain fuel injection or a braking system in detail. Modern life makes this normal.

The difficulty is psychological: access to knowledge begins to feel like possession of knowledge.

A related problem is the illusion of explanatory depth. In their 2002 study, Leonid Rozenblit and Frank Keil found that people overestimated how deeply they understood complex phenomena. Attempting an explanation can expose a gap that familiarity had concealed.

Try the question on a familiar device: could I explain how each part contributes to its operation, without looking up the answer? Knowing how to use something may not prepare me to explain its mechanism. The difference becomes easier to notice when I try.

I like this exercise because a missing explanation identifies something to learn. It need not become a judgment about intelligence.

Relying on other people is unavoidable. The useful discipline is to distinguish what I can explain myself from what I trust someone else to explain.

The problem becomes more serious when mechanisms disappear but opinions remain. We may speak confidently about economics, artificial intelligence, medicine, education, or public policy while carrying only a compressed summary of somebody else’s explanation.

That does not mean we should remain silent unless we are experts. Nobody can rebuild modern civilization inside one mind. The useful distinction is between knowing something and knowing where our confidence comes from.

Did I examine the mechanism myself? Am I relying on a specialist? Did I read one persuasive summary? Am I repeating what people around me already believe?

Those are not equally strong positions, even when they produce the same sentence.

This is why explaining an idea is such a useful test. Explanation forces borrowed certainty to become visible. The missing steps begin to show themselves.

I do not think intellectual humility means saying “I know nothing.” That can become another performance.

It means keeping the border between my understanding and the world’s understanding visible.

A great deal of knowledge is available to me.

Much less of it is actually mine.