The function of education is to teach one to think intensively and to think critically.
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A team of MIT researchers ran an experiment that should stop every leader in their tracks.
They asked 54 people to write essays. Some used ChatGPT. Some used a search engine. Some used only their own brains.
The whole time, the researchers measured electrical activity in their heads.
The ChatGPT group showed the lowest brain engagement of the 3, by a wide margin.
It got worse over time. By the third essay, many of the AI users were barely engaging at all. Copy, paste, submit.
When the researchers later asked them to write without AI, they couldn't recover the engagement. The mental muscle had gone quiet.
The team gave it a name. Cognitive debt.
You borrow against your own thinking today. The bill comes due later, in diminished critical inquiry, weaker creativity, and more vulnerability to whatever you're told.
A separate study from Microsoft and Carnegie Mellon found the same pattern in the workplace. The more confidence knowledge workers placed in AI, the less critical thinking they did.
Critical thinking was already in short supply long before ChatGPT showed up.
Now we've handed millions of people a tool that does the thinking for them. The skill was rare. It's getting rarer.
That's the risk. It's also the opportunity. Because the people who keep their minds sharp are about to stand out more than ever.
I created a breakdown of 7 thinking styles that make you sharper at work and life. Click the thumbnail for the high-res version.
Thinking is not one skill
Most people treat thinking like a single thing. You're either smart or you're not.
That's wrong. Thinking is a set of distinct modes. And most professionals only ever use 2 or 3 of them, on autopilot, for their entire careers.
The leaders who stand out know which mode a problem calls for, then deliberately switch into it. Here are the 7 worth building.
Critical thinking. Checking facts, assumptions, and sources before you decide. This is the one AI erodes fastest. Apply it by asking one question of anything you read or any answer AI hands you: "How do I know this is true?" Then go verify it.
Analytical thinking. Breaking a big problem into smaller parts to see how it works. When something feels overwhelming, don't attack the whole thing. List the 3 to 5 components, then solve them one at a time.
Creative thinking. Connecting ideas in new ways to find fresh solutions. When the usual approach stops working, ask "What would I try if the obvious option were off the table?" Force a second answer.
Abstract thinking. Looking at big ideas and patterns instead of just the details in front of you. Before diving into a problem, zoom out and ask "What is this really about?" The surface issue is rarely the real one.
Concrete thinking. Focusing on facts you can see, hear, or measure. When a conversation drifts into theory and opinion, pull it back. Ask "What do we actually know right now?" and decide from there.
Convergent thinking. Gathering the clues to land on the single best answer. Useful when you have options on the table and need to commit. Define your criteria first, then narrow to the one choice that fits them best.
Divergent thinking. Generating many ideas quickly without judging them yet. This is how you start, not how you finish. Set a timer for 5 minutes and write down 10 possibilities before you let yourself evaluate a single one.
Why this matters more now
Notice something about that list.
AI is good at a few of these. It can break things down. It can generate dozens of options in seconds.
What it cannot do is decide which mode your specific situation calls for. Or judge whether its own answer holds up. Or sense that the surface problem is hiding a deeper one.
That judgment is critical thinking. It sits on top of all the others. And it's exactly the muscle the research says we're letting atrophy.
The Microsoft study found one bright spot worth holding onto. People with high confidence in their own ability did more critical thinking, not less, even while using AI.
So the answer is not to avoid the tools. Use them. Lean on them.
Just don't outsource the thinking itself. Stay in the driver's seat. Make AI prove its work the way you'd make a new hire prove theirs.
My dad used to say the mind is a muscle. Use it or lose it.
The science finally caught up to him.
So this week, pick one decision that matters.
Run it through more than your default mode. Break it down with analytical thinking. Stretch it with divergent. Pressure-test it with critical. Then commit with convergent.
And the next time AI hands you a confident answer, ask the one question that keeps your edge sharp.
"How do I know this is true?"
Talk soon,
Justin
P.S. What's one app you'd genuinely struggle to live without? Hit reply, I'm curious.
