Odd this day
6 January 1995
I haven’t had time to write this up properly, but it’s the 31st anniversary today of the bank robberies which gave the world the Dunning-Kruger effect, when two men concealed their identities by the brilliant method of smearing their faces with lemon juice.
Here’s an extract from an article called Trial & error in the Pittsburgh Post-Gazette in March the following year (which also includes the tale of a man who applied for a job at a restaurant using his real name, address, and social security number a matter of minutes before robbing the place).
The Invisible man
At 5 feet 6 inches and about 270 pounds, McArthur Wheeler is an easily recognizable man even when wearing lemon juice on his face.
That certainly came as a surprise to Wheeler, 45, of Versailles Street, McKeesport. He was incredulous in April when Pittsburgh robbery detectives told him that he had been identified in surveillance photographs as one of the two men who robbed two banks in Brighton Heights and Swissvale on Jan. 6.
“But I wore the lemon juice. I wore the lemon juice,” a puzzled Wheeler told the even more puzzled detectives.
The detectives’ confusion turned to incredulity as Wheeler explained about his would-be lemon aid.
“Someone told him that if you put lemon juice on your face it makes you invisible to the surveillance camera,” recounted a still chuckling Cmdr. Ronald Freeman of the investigations branch. “He was skeptical at first but not so much as to not try it himself.”
“He said the lemon juice was burning his face and his eyes, and he was having trouble [seeing] and had to squint,” said Sgt. Wally Long of the robbery squad.
But the pain was worth the pleasure Wheeler felt when he snapped a Polaroid picture of himself and he wasn’t anywhere to be seen..
“When the Polaroid didn’t show him, he thought it worked,” Long said.
All that detectives could figure was that either the film was bad, Wheeler hadn’t adjusted the camera correctly or he had pointed the camera away from his face when he snapped the photo.
“In any event, he went off and robbed the banks with lemon juice on his face,” Freeman said. “He was shocked when we showed him the surveillance pictures.”
Detectives had been tipped to his whereabouts in Lincoln-Lemington by informants who recognized him in one of the surveillance photos taken during the robberies. The photo had been telecast during the Pittsburgh Crime Stoppers Inc. segment of the 11 o’clock news April 19. Less than an hour after the broadcast, he was arrested at 202 S. Fairmont St.
Wheeler was convicted in federal court in the Swissvale holdup. Charges in the Brighton Heights case were dropped.
As Justin Kruger and David Dunning of Cornell University put it with admirably straight faces three years after that:
People tend to hold overly favorable views of their abilities in many social and intellectual domains.
As I say, not had time to write this up properly, but I did come across this fun thing in the NYT in which documentary maker Errol Morris talks to David Dunning, who sums up his findings as
if you’re incompetent, you can’t know you’re incompetent … We’re not very good at knowing what we don’t know.
…which leads to this observation:
ERROL MORRIS: Knowing what you don’t know? Is this supposedly the hallmark of an intelligent person?
DAVID DUNNING: That’s absolutely right. It’s knowing that there are things you don’t know that you don’t know. Donald Rumsfeld gave this speech about “unknown unknowns.” It goes something like this: “There are things we know we know about terrorism. There are things we know we don’t know. And there are things that are unknown unknowns. We don’t know that we don’t know.” He got a lot of grief for that. And I thought, “That’s the smartest and most modest thing I’ve heard in a year.”
…which I rather liked. If people’s objections to that Rumsfeld soundbite had been ‘this stopped clock has finally told the right time’, they’d have been sound, but for the most part it was ‘that guy’s evil, so I’m dismissing what he just said even though it’s true if I stop and think about it’. (Or, as someone pointed out on Bluesky earlier, “more like ‘he said something I don’t understand, he must be stupid’. Which is a Dunning-Kruger symptom too…”)
If you want thudding banality on this issue, I would instead point you towards April 2023’s British Dental Journal which says:
Overconfidence due to the Dunning-Kruger effect has the distinct possibility of leading to patient harm.
Which isn’t too bad on its own, even if it does feel like shoehorning in the point they’re making, but then we get the bit that belongs on LinkedIn, rather than in a scientific journal:
Fortunately, there’s a straightforward strategy to combat this problem. And that is one of education, teamwork and collaboration. By learning the difference between a good and a bad performance, we discover what we should be doing and, equally importantly, what we should avoid. And dentists who know their abilities and limitations can better refer on when needed, improving patient safety.
But I rather love the fact that he does this. What could be more appropriate in an article on Dunning-Kruger than misplaced certainty that you have something profound to say?
Anyway, more about the successful (in the short term) robberies and their long-term repercussions here: