Ever heard of Dunning and Kruger or the Dunning–Kruger Effect? MacArthur Wheeler?
Thirty years ago in Pittsburgh, a man walked into a bank at 2:00 p.m. No mask, no weapon — he calmly and confidently handed a teller a note demanding cash. An hour later, he did the same at a second bank. He made no attempt to avoid cameras, just walked out the door, calm as could be. I see him whistling without a care in the world as he walks down the sidewalk.
By that evening, MacArthur Wheeler’s face was all over the nightly news. He was arrested before midnight.
The news reports grabbed the attention of David Dunning, a professor of psychology at Cornell University, who shared the story with his graduate assistant, Justin Kruger. We should note that the mid-90s marked the peak of U.S. bank robberies — the FBI reported 9,388 in 1995. So, why was this one so interesting to Dunning and Kruger?
Wheeler had no criminal record, no history of mental illness, and was by all accounts a normal guy. That said, he was out of a job, which sparked a desperate move. He’s not violent, doesn’t want to hurt anyone, but desperately needs money. He begins to research and plan a bank robbery.
Wheeler somehow discovered that a key ingredient of invisible ink was lemon juice. He theorized that lemon juice might affect a camera’s ability to capture an image of a face, if it was covered in lemon juice. So, a test. Sitting in his apartment, using actual lemons — a little messy and likely uncomfortable — he covered his face with lemon juice, grabs his Polaroid camera, and takes a selfie. The darkened, white-framed photo rolls out; he executes the traditional “Polaroid shake.” During this process, a stray lemon seed or drop of juice hits the center of Wheeler’s undeveloped photo, leaving a dark, blurry blob where his face should have been.
Proof!
So, when the cops showed up later that night, Wheeler was stunned: “But I wore the juice!”
This fact is what made the case so interesting to a couple of psychologists and inspired them to research, and ultimately present the Dunning–Kruger Effect—the cognitive bias where people with limited understanding overestimate their competence, often dramatically.
Their 1999 study showed that when knowledge is limited, self-awareness often is too. People tend to overestimate their competence because they don’t know, what they don’t know.
Since I read this story and have familiarized myself with the research, I feel like I see it everywhere. Markets overflow with data — economic reports, earnings calls, political headlines, and constant opinion.
Too much information can paralyze; too little can mislead.
In addition to the real “experts”, we have an ocean of social-media sound bites and outright fake information designed to grab our attention and quickly convince us that… this is it!
You will make millions, replace your income, lose 50 pounds, be smarter, prettier… maybe even invisible to cameras!
The following is in no way a complaint — keep them coming. That said, I receive three or four articles, links, or videos each week essentially asking, “Is this something we should look at or be aware of?”
Our role is to help maintain a balance: to filter the flood of data, test assumptions, and translate uncertainty into purposeful action. Using rigor, analysis, and discipline, we keep our counsel grounded in process rather than prediction.
If I ever catch myself thinking, “this can’t miss,” “this time is different,” or “I’m certain X is going to happen,” that’s my cue to pause. I may not need more conviction — I probably just need more information.
