Borrowing Knowledge

I noticed something recently that’s been bothering me. I was trying to explain a concept I use all the time—something I’d reference fluently in conversation without a second thought—and when I stripped out the jargon, I couldn’t quite get there. I could use the word, I could deploy it in a sentence that sounded right. But when I tried to describe the actual mechanism underneath—what causes what, how it works, why it matters—the explanation fell apart.

The vocabulary was smooth but the understanding was full of holes I hadn’t noticed.

The Name and the Thing

Richard Feynman—the physicist, not exactly a business guru—made a distinction I keep coming back to. He argued that knowing the name of something and understanding it are entirely different acts. You can learn the word “gravity” without having any real sense of what gravity does. You can be fluent in a vocabulary without grasping a single mechanism underneath it.

His test was characteristically simple: try to explain the thing to a child. Not dumbed-down—translated and concrete. If you can describe what’s actually happening—what causes what, what changes when conditions shift, why it matters—in language a twelve-year-old could follow, you probably understand it. If you can’t get there without reaching for the technical term, that’s not a vocabulary problem, it’s a comprehension problem.

There’s an image from the Feynman method that stuck with me: we tend to think our knowledge is a smooth, paved highway—a continuous understanding with no breaks. But usually it’s more like a series of islands with rickety little bridges between them. Each piece of jargon is a sign posted on an island. It doesn’t tell you whether there’s a solid bridge to the next concept or just open water you’ve been stepping over without noticing.

The place where the explanation breaks down—where you reach for the technical term because you can’t say it plainly—is the rickety bridge and where the understanding hasn’t been built yet.

Borrowed Versus Owned

There’s a useful distinction here between knowledge that’s borrowed and knowledge that’s owned. Borrowed knowledge is language you can deploy without a mental model behind it. You can use the word in a sentence, you can nod along when someone else uses it. But if someone pressed you on the mechanism, you’d stall. Owned knowledge is different—you’ve built it from the ground up. You can explain it, apply it in new situations, and recognize when it doesn’t hold.

Most of us are operating on more borrowed knowledge than we realize. The frameworks we’ve absorbed, the terminology we’ve picked up, the concepts we reference because we’ve heard them referenced—these give us fluency. Fluency is genuinely useful. But fluency isn’t understanding, and the gap between the two is easy to miss because the fluency feels so much like comprehension.

I’ve caught this in myself, sometimes. It happens with concepts I’ve used for years—confidently, in conversations where no one pushed back—that I couldn’t explain from first principles if someone asked me to slow down and walk through the actual mechanism. The labels were doing the work. My understanding was thinner than my vocabulary suggested.

Feynman put it bluntly: you cannot fake simplicity. Complexity is a place to hide, but simplicity is naked.

Why the Gaps Hide

The part of this I find most interesting is why these gaps persist—sometimes for years—without being noticed.

Most environments reward fluency over understanding. The person who speaks confidently in the right vocabulary sounds competent. The person who pauses and says “I’m not sure I actually understand how this works” sounds like they’re behind. So the incentive is to perform understanding—to sound like you know—rather than risk the vulnerability of admitting you don’t.

In a business context, Edmondson’s research on psychological safety is relevant here, though in a slightly different way than it’s usually applied. The safety question isn’t just whether a team can disagree openly. It’s whether people can admit, to themselves and to each other, that they don’t fully understand something they’ve been talking about fluently. That’s a different kind of vulnerability. It’s not “I disagree with you.” It’s “I’ve been nodding along, but I don’t actually get this.”

Feynman warned that the first principle is not to fool yourself, and that you’re the easiest person to fool. When you add the social dynamics of a team or a professional environment—where fluency is rewarded and confusion is stigmatized—the fooling compounds. Everyone uses the same words. Everyone assumes everyone else understands. The shared vocabulary becomes a shared blind spot.

The Blank Page

Feynman’s method for breaking through this is almost absurdly simple. Take a blank page. Write one concept at the top—something specific, not an entire field. Then try to explain it in plain language, as if to a sixth grader. No technical terms, no jargon; just: what’s actually happening here? What causes what? Why?

Wherever the explanation breaks down—wherever you feel the pull to reach for the technical term because you can’t say it simply—mark that spot. That’s the gap, and that’s where you thought you understood but didn’t.

Then go back to the source material with those specific gaps as questions. Not rereading everything from the beginning—hunting for the missing piece. Fill the gap, return to the explanation, and try again until the whole thing flows as a plain-language narrative that a kid could follow.

It sounds almost too basic to be useful. But the power is in the honesty it forces. You can’t fake the plain-language explanation. Either you can describe the mechanism concretely or you can’t. The jargon has nowhere to hide.

What You Actually Know

I’ve been running this on myself. Picking concepts I use regularly and putting them through the blank-page test. The results have been humbling. Some things I thought I understood well, I did. But others—things I’ve been fluent in for a long time—turned out to have significant gaps I’d been stepping over without realizing.

The honest version of what happened is that the labels were giving me a sense of completion that the understanding hadn’t earned. The word was there, so my brain marked it as known. The blank-page test forced me to look behind the word, and behind it was less than I expected.

I think this matters beyond the personal level too. When a team shares vocabulary without shared understanding, they can talk past each other for a long time without noticing. The language creates the appearance of alignment. The gaps only surface under pressure—when a decision comes along that doesn’t fit the familiar vocabulary, and each person fills in the mechanism differently.

But the starting point is individual. It’s sitting with the uncomfortable question: of all the concepts I use fluently, how many could I actually explain—simply, concretely, from the ground up—without the jargon doing the work for me?