Unknown Unknowns

I’ve been thinking about this for over a decade now. It all started with a simple story about swans—black ones, to be specific.

In 1697, Europeans encountered something they never imagined possible: a swan that wasn’t white. For their entire lives, “swan” meant white. Like Swan Lake, like every painting, every story, every mental image they ever had. Black swans simply didn’t exist in their mental universe. Until they did.

Image Credit > https://en.wikipedia.org/wiki/Black_swan

This reminds me of a framework that’s stuck with me ever since—the idea that knowledge can be categorized into four types. It’s not original to me, but it’s something I keep coming back to, and the older I get, the more I realize which category matters most.

The Four Types of Knowledge

1. Known Knowns We both know what an apple is. It’s red or green, crunchy, sweet or sour. When I say “apple,” we’re on the same page. This is simple shared knowledge—no surprises here.

2. Known Unknowns We know we don’t know something. UFOs, for example. We’ve seen the footage, heard the reports, but we can’t explain them. We admit our ignorance. It’s uncomfortable, but at least we’re aware of the gap.

3. Unknown Knowns This one’s strange. It’s the stuff you know but don’t know you know. Like hidden skills or buried instincts. You normally run 100 meters in 20 seconds—nothing impressive. But then you encounter a bear in the forest, and suddenly you’re covering the same distance in 15 seconds. Your body knew something your mind didn’t. It’s fascinating, but not the point of this piece.

4. Unknown Unknowns This is the big one. The territory you don’t even know exists. You can’t seek what you can’t name. You can’t question what you can’t imagine. These are the blind spots that shape our lives without us ever realizing it.

Why This Matters More Than You Think

Here’s what gets me: the more I learn, the more I work, the more I live, the more I realize I’m swimming in category four.

We like to think we’re rational, informed, aware. But what about all the things we’ve never considered? The assumptions we don’t even know we’re making? The possibilities we’ve never imagined because our mental models are too small?

It’s humbling. And I think that’s a good thing.

How to Discover What You Don’t Know You Don’t Know

You can’t exactly Google “things I don’t know I don’t know.” But you can create conditions for discovery. Here’s what’s worked for me:

Cultivate Radical Curiosity

Go beyond just asking “why” like a child—use your curiosity to dig. For me, genuine curiosity has always been an obsession with pulling at threads to see what happens behind the curtain. Don’t just accept that a system works; dig into how it works. When you dive deep into the mechanics of things, you drag the “unknown unknowns” into the light.

Reverse-Engineer Success and Failure

Don’t wait for things to go wrong to learn. When you see a massive success, study the hidden variables the winner ignores but you can’t afford to. When you see a failure, dig into the invisible trap that caused it. And step across your role boundaries—participate in sales meetings as a technical engineer, sit in on architecture reviews as a salesperson. When you operate outside your job description, you discover what you never knew about how the whole system actually works. The unknown unknowns live in the gaps between roles, between what succeeded and what everyone assumed would succeed.

Study Adjacent Domains

Don’t just read widely—study mental models from fields that have nothing to do with yours. If you work in tech, study biology. If you’re in finance, study evolutionary psychology. When you import a framework from one world and force it onto another, you expose the blind spots that your own industry’s “common knowledge” has been hiding from you. Every field has its own unexamined assumptions. Borrowing someone else’s lens is the fastest way to see your own.

Question Everything

Never simply believe what you are told. This is especially true in the age of social media, where trends imply a collective truth that often lacks substance. If you accept information at face value, you are relying on someone else’s knowledge rather than building your own. Challenge the status quo. Ask: Why is this trending? What is the evidence here? What is being left out of this narrative? By thinking suspiciously and verifying, you uncover the assumptions that everyone else has blindly accepted.

The Point

I don’t have this figured out. I still catch myself making assumptions I didn’t know I was making. I still discover entire categories of things I never thought to question.

But that’s the beauty of it. The world is bigger than our mental models. And the moment you think you’ve got it all mapped out—that’s precisely when you’re missing the most.

Stay curious. Stay humble. And remember: what you don’t know you don’t know might be the most important thing of all.