NOTE: This post is Part 2 in my month-long deep dive into exploring "expertise and authority." Go here to read the first post.

And get the whole series (as it progresses) here.

How to rob a bank with a lemon:

  1. First, choose the right lemon. It should probably be a big one. You might need multiple lemons, actually. Let's say three. 
  2. Squeeze the lemon(s) into a receptacle. Maybe a big bowl. Something you can really get your hands into. Also your face.
  3. Using your hands, scoop the lemon juice out of the receptacle and spread it liberally over your face. It's recommended that you keep your eyes closed during this step. 
  4. Your face is now completely invisible to cameras! This is due to a scientific principle we read once in an article about "things to do with your kids on a rainy day." Lemon juice can be used as invisible ink, only readable if you expose it to heat. So science
  5. Stay away from heat sources.
  6. Walk into any bank, confident in your invisibility, and collect your loot! 

That's the plan McArthur Wheeler executed flawlessly in 1995, when he deduced that lemon juice was the key to walking away with all the money he'd ever need. He faithfully executed these steps (or similar ... I pretty much just made up the actual steps), and for good measure took a selfie with a Polaroid camera to verify his hypothesis. Somehow, through some hysterical quirk in 1990s-era technology, the photo proved him out. HIs face was obscured. His confidence was assured. 

McArthur Wheeler was now an expert of facial invisibility. 

Of course, his expertise led to folly (a phrase I've been dying to write). Because, honestly, lemon juice is not going to make your face invisible to security cameras. It might make you one of the most pleasant smelling bank robbers around, though. And it will give you a nice, zesty flavor when you go to prison. Mull that over. 

Ignorance more frequently begets confidence than does knowledge.
— Charles Darwin




This quote from Charles Darwin, the father of modern evolutionary theory, is kind of profound. It explains a lot, actually, about why Mr. Wheeler strode with confidence into not one but two banks that day, face dripping with lemon juice, assured of his iil-gotten wealth.

People tend to be a lot more confident about their own abilities if they're ignorant of their own limitations. 

We see this all the time in less larcenous circumstances. The guy who insists he can fix the clogged kitchen sink, only to make a huge mess because he knows nothing about plumbing. Or the woman who ruins a skirt while adjusting the hem because sewing doesn't seem all that hard. Or the kid who finds himself in over his head because he convinced his friends that he knew how drive a car.

We do this stuff. We overestimate our own knowledge and skill, or we underestimate the difficulty or complexity or even the improbability of what we're doing. We get confident, even when that confidence isn't justified.

A friend recently pointed me to an article on Wikipedia about the Dunning-Kruger effect (where, incidentally, I first encountered McArthur Wheeler's story). This is a "cognitive bias," or "a pattern in deviation of judgment" that was explored in a 1999 study conducted by David Dunning and Justin Kruger at Cornell University. As their report put it:

"People tend to hold overly favorable views of their abilities in many social and intellectual domains. "

SOURCE: Pulled from the abstract for Unskilled and unaware of it: How difficulties in recognizing one's own incompetence lead to inflated self-assessments.
APA PsychNET, Journal of Personality and Social Psychology, Vol 77(6), Dec 1999, 1121-1134.

Basically, it was a study of incompetence.

I know nothing about CV joints

People sometimes believe that they know more than they think they do about a given subject. They may have some experience with or exposure to the subject that was overtly positive and affirming, even if that experience or exposure wasn't complete. And this, unfortunately, gives some people the sense that "I got this. I'm naturally an expert at this."

I'm not going to lie, I have done this. I'm not going to say you have (but you have) because I'm no expert on you (but you have). But in general, humans can be a bit overconfident about what they actually know, and their own level of expertise, and that confidence can lead to disaster.

When I was in my 20s I owned a Mazda Protege. I bought it new, but got it at a discount because it had quite a bit of hail damage. To this day I'm not sure why I as ok with that. The discount wasn't that much. But a discount is a discount, and I've been a bargain hunter from day one.

This wasn't my first car, but it was the first one I bought with my own money. And so I was determined to take care of it, keeping it maintained and running like a Swiss timepiece.

Thing is, I'm not much of a mechanic. In fact, for a large part of my adult life I was what can only be described as "completely irresponsible" when it came to cars. This baffled my grandfather—the consummate shade tree mechanic who could (and would) fix anything himself. No matter how patiently he explained things to me, how lovingly he showed me the work in progress, it didn't quite click with me at the time. I just didn't have much interest. And this meant that I drove my cars until pieces started falling off of them.

After a few years of driving my hail-beaten Protege hundreds of miles a day between college, work, and home, the CV joints started to go out. So I turned to a good friend of mine—whom we will call "Joe" for everyone's protection and the sake of our friendship. He confidently told me how simple and easy it was to replace those joints. We could do it ourselves, save me thousands of dollars, and I'd be on the road again in a hour or two.

I paid for the parts, the fluids, and even dinner, and the two of us commandeered his father's driveway and tools (and a couple of his cigars) and got to work. 

Twelve hours later we finally figured out how to get everything back together. Sort of.

Over the course of those twelve hours, we ran into one problem after another. We neglected to put down a pan to catch the fluid as it leaked out, after pulling the CV joints free. We realized partway through that we had something installed wrong or backwards, and had to start over. We had trouble getting the brakes off and then on again. And, about three hours in, Joe says, "I have no idea what I'm doing." And a part of me died that day. 

We did rally. We got it together. We found a manual for the car, puzzled over the pieces, consulted mechanics at the local shop, and eventually we figured out how to do the work. Again, sort of.

From that day forward, the Protege had all kinds of weird issues and problems and quirks that never existed before. About nine months later I traded it in and got something else.

What went wrong here? Joe wasn't completely ignorant of mechanics. I knew from personal experience that he worked on his own cars, that he and his father even had a race car and a small "get around the ranch" vehicle they'd built from spare parts. He regularly told me about his mechanical prowess, about the work he'd just done on the race car, about the parts he just got in and was installing himself, his hands covered in motor oil that also, surely, ran in his own veins. 

The bad assumptions here started with my friend, obviously. He had worked on a couple of cars, mostly with assistance from his very knowledgable and confident father, and so he felt he had this. He knew what he was doing. He'd done it before. At least, he'd been present when it was done before, so he knew.

I made assumptions, too. I assumed that because he was doing work I wasn't competent in, he had to be an expert. I overestimated his level of competence because it was greater than my own. I assumed I knew the expert, that I had vetted him thoroughly. My confidence in my ability to asses the skills of Joe the mechanic was very high, and very misplaced.

The Dunning-Kruger effect was at work on both of us as we crawled around under that car, cursing about the most recent obstacle, and me getting more and more anxious as the hours went by. I was practically sobbing with worry and frustration as I drove home in my car the next day, brakes making odd noises and everything feeling slightly "off." 

The danger of claiming expertise and authority is that it may be built on assumptions like these. We may be fooling ourselves into thinking we know a lot more about something than we actually do, just because it seemed easy to us at some point. 

We're terrible at assessing our own competency

In the Dunning-Kruger study, the researchers determined that people scoring in the 12th percentile on tests of humor, grammar and logic tended to overestimate their ability in each, and estimated that they were actually in the 62nd percentile. In other words, though they scored very poorly, they were confident they had done much better than anyone else. If they bombed, it was because the information was highly specialized, so only an expert like them could even hope to get as far as they did.  

Inversely, the people who scored highest tended to underestimate their abilities. And here's where things get really interesting. Because the reason for the underestimation was the conclusion that if the task seemed easy to them, it must be easy for everyone. So they assumed they were merely average, rather than above average.

When people refer to the Dunning-Kruger effect, the tendency is to focus on the aspect of incompetence, pointing out that most of us think we're more competent than we actually are. We think we're funny. We think we're technically skilled. We think we're compassionate. But according to Dunning-Kruger, we're a terrible judge of our own competence in all of these things. Because either we are actually incompetent and think we're not, or we're completely competent but think we're average. 

But wait ... there's hope! Because Dunning and Kruger also noted that with education, we can become better at assessing our own level of competency even if we do not improve in the skill we're trying to master.

In other words, once we know how ignorant we really are, we're better at estimating our level of ignorance.

That's not a new concept at all. In fact, embedded in the Wikipedia article that sparked this post are several quotes from some of the most respected figures in history:

Real knowledge is to know the extent of one’s ignorance.
— Confucius
I know that I know nothing.
— Socrates
One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision.
— Bertrand Russel
The Foole doth thinke he is wise, but the wiseman knowes himselfe to be a Foole.
— Shakespeare

Four geniuses of history, one theme: We're smarter when we know that we don't know everything. 

So what does the Dunning-Kruger effect mean for expertise and authority? 

It doesn't change the intrinsic and essential definitions we already have. But it does caution us to pause and re-examine what we actually know versus what we think we know. 

If you are being approached for your expertise, then you are at least recognized for you competency by someone other than yourself. That's good. But it doesn't automatically mean you are the most competent expert. It means you are trusted as a source by that audience, that you do have some special knowledge and experience, and that you are capable of relaying that competency in a way that people value. 

The danger comes in assuming we know everything about our subject. When we decide that, because we are experts, all we know is all there is to know, we can end up in prison with lemon juice on our face.

Likewise, don't assume that just because something comes easy for you, it means that it is easy. Your knowledge and experience are different than that of anyone else, always. Your perspective is different. So you may have inside information that is missing from those around you, even if they happen to be experts in the same field. 

That's why you can read three books written by the biggest experts in a field and potentially know more about a subject than those experts themselves. Possible? Yes. Likely? Maybe not. But the possibility is the point, after all, and you can at least be confident that you are much more of an authority on the subject than the person who has read no books or spent no time in research.

The takeaway from this is that we are often poor judges of our own competency in a subject. So the safest bet is to assume that we don't know everything, to accept that ignorance as a challenge to improve, and to accept that challenge as part of our daily work. We can still be experts and authorities—and maybe even better experts and authorities—if we acknowledge our own shortcomings and work hard to overcome them.

Like what you're reading? Consider tipping the author!

Tip in any amount you like, safely and securely via PayPal (no PayPal account requred). And thank you in advance for your generosity!

Kevin Tumlinson is the author of numerous novels, novellas, and non-fiction books, and the host of the Wordslinger Podcast. Try three of his best books for free when you download his starter library at


Get updates on new books, new posts, and new podcasts, plus be the first to hear about special offers and giveways. And pants jokes. Lots and lots of pants jokes.