this post was submitted on 08 Sep 2025
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Today I Learned

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[–] acockworkorange@mander.xyz 82 points 1 day ago (1 children)

The world needs more humble geniuses. We're few and far between nowadays.

[–] Clent@lemmy.dbzer0.com 3 points 1 day ago (1 children)

The world has plenty. They just aren't on social media.

[–] acockworkorange@mander.xyz 9 points 1 day ago (1 children)

I think you missed my sarcasm.

[–] WR5@lemmy.world 3 points 1 day ago

Well, they were right; not a genius because they are on social media.

[–] hperrin@lemmy.ca 71 points 1 day ago (9 children)

The more I’ve learned about email while writing my own email server, the more I’ve realized I knew basically nothing about email when I started. Now, I’m at least somewhat knowledgeable, but god damn it’s so fucking complicated. Even something as seemingly straightforward as email has such a deep complexity that it takes years of study to even approach being an expert.

The single most useful thing I’ve learned doing this is that you should never assume you know a lot about a topic. There are a. always more things to learn, and b. always people who know more than you.

[–] roofuskit@lemmy.world 40 points 1 day ago (2 children)

I have long said the only truly stupid people in the world are those who think that have nothing left to learn.

[–] themeatbridge@lemmy.world 12 points 1 day ago

I like that line. I'm stealing it. Might paraphrase to fit the situation.

I did technical trainings, and I always used to say that the only stupid question is the one you don't ask.

[–] Aceticon@lemmy.dbzer0.com 4 points 1 day ago

"All I know is that I know nothing", Socrates.

With time I came to understand this as meaning that there's always far more left to learn than one could possibly know.

Maybe not the original meaning (the whole Cave Allegory apparently comes from him via Plato, so maybe it's about how the World is not really what we perceive), but it kinda fits.

[–] HamsterRage@lemmy.ca 25 points 1 day ago (1 children)

This is, of course, a perfect example of D-K in action. This dude is writing his own email server, FFS, and he characterizes himself as, "at least somewhat knowledgeable".

I've read a bunch of the old RFC's for email services years ago, when you needed some of that info in order to do interesting things with sendmail. I figure that might have put me in the top 20% of programmers/admins/techies back in the day. But to actually consider writing an email server - no way. That's a different level of "at least somewhat knowledgeable" .

[–] shalafi@lemmy.world 6 points 1 day ago (1 children)

The 500 mile email comes to mind.

https://www.ibiblio.org/harris/500milemail.html

Next. Level. Troubleshooting.

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[–] jimmux@programming.dev 16 points 1 day ago (1 children)

"I'll just validate email addresses with a bit of regex. How hard could that be?"

[–] hperrin@lemmy.ca 13 points 1 day ago* (last edited 1 day ago)

Right!? Fun fact, this is a perfectly valid email address:

"Pooper Scooper 💩"@[69.69.69.69]
[–] vala@lemmy.dbzer0.com 14 points 1 day ago (1 children)

Running your own email server is a dark and lonely road that can only lead to crippling insanity. We can thank Google for that.

[–] hperrin@lemmy.ca 9 points 1 day ago

I’m definitely aware. I run an email service at https://port87.com/. Google is absolutely awful to deal with.

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[–] flop_leash_973@lemmy.world 47 points 1 day ago* (last edited 1 day ago) (3 children)

A mindset I just fell into as a much younger man for reasons I no longer remember was assuming everyone knew more than I did and did things the way they did them for a reason. And I should learn what that reason is before I go proposing changes.

That mindset has never steered me wrong. Even when I change something someone else put in place what I come up with is a better solution for taking the time to understand why the previous person did it the way that they did.

[–] Bakkoda@sh.itjust.works 19 points 1 day ago

I had a soccer coach from age 7-18. Same guy, brilliant dude, Dean of law at a very large state school. He told me at 12 to never talk to the other kids at the summer camps (competition) about what i was working on. "Just go out and do it and shut your mouth about it. That's how you impress on the field."

It's stuck with me since then.

[–] bravesirrbn@lemmy.world 7 points 1 day ago

This principle is sometimes called "Chesterton's Fence" (https://en.wiktionary.org/wiki/Chesterton%27s_fence)

[–] shalafi@lemmy.world 7 points 1 day ago

So much anger I see in the world is directed at policies, laws, procedures, whatever, that make perfect sense if one understands the background.

Sucks, but we can't all understand everything. I try, but I ain't that smart, and certainly can't be that experienced.

[–] Lushed_Lungfish@lemmy.ca 45 points 1 day ago (2 children)

I find that folks that just keep their mouths shut, do their jobs quietly, competently and correctly are far better to have on your team than the loudmouth know-it-all.

Bonus is that when the former does open their mouth you know you should be paying attention.

I think they call it "quiet competence".

[–] Coldcell@sh.itjust.works 10 points 1 day ago

All too common I've seen those loudmouths promoted, and the quiet competent are then talked down to about something they know far more about. Then they leave.

Middle management doesn't understand a skillset unless someone tells them directly they are skilled, it's a culture of failure.

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[–] original_reader@lemmy.zip 23 points 1 day ago

People who think they know everything are a great annoyance to those of us who do.

— Isaac Asimov

[–] Onomatopoeia@lemmy.cafe 16 points 1 day ago (8 children)
[–] Aatube@kbin.melroy.org 30 points 1 day ago (3 children)

Could you elaborate? From what I read, Dunning and Kruger did find a real phenomenon where people with limited competence in a domain overestimate their ability, but they did not suggest these individuals thought they were smarter than experts; and one theory holds that it is a statistical truism, which still means it exists.

[–] ZephyrXero@lemmy.world 15 points 1 day ago (2 children)

What happens is people have the Dunning Kruger effect on the Dunning Kruger effect itself. People call it up far too often and misuse the label

Yeah, as far as I know, it hasn't been disproven. Its scope has narrowed and is more nuanced. And it has made its way into the public lexicon like PTSD, OCD, ADHD, etc. so it gets thrown around a lot.

[–] sp3ctr4l@lemmy.dbzer0.com 4 points 1 day ago* (last edited 1 day ago) (4 children)

That is not the same thing as being disproven though.

Thats like saying 'trauma bonding' isn't real...

...because most idiots on TikTok incorrectly think it means bonds generated through shared struggles.

As opposed to what it actually means, which is basically when someone normalizes being traumatized in an abusive relationship with someone who is very manipulative by way of this other person generally offering only negative reinforcement nearly all of the time, with tiny morsels of occasional positive reinforcement handed out only after absurd feats from the 'trauma bonded' person.

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[–] radix@lemmy.world 10 points 1 day ago

I've often heard it's misunderstood and used in inappropriate situations, but it's still a real phenomenon.

Like laypeople tossing around "OCD" when they shouldn't. Absolutely real, but not in the same way that it's commonly used.

[–] JackbyDev@programming.dev 8 points 1 day ago* (last edited 1 day ago) (4 children)

They're probably talking about this. It's been too long since I read it so I won't be discussing it, but I'll share a paragraph so folks don't have to click the link to see the gist. https://economicsfromthetopdown.com/2022/04/08/the-dunning-kruger-effect-is-autocorrelation/

The Dunning-Kruger effect also emerges from data in which it shouldn’t. For instance, if you carefully craft random data so that it does not contain a Dunning-Kruger effect, you will still find the effect. The reason turns out to be embarrassingly simple: the Dunning-Kruger effect has nothing to do with human psychology.1 It is a statistical artifact — a stunning example of autocorrelation.

[–] sp3ctr4l@lemmy.dbzer0.com 5 points 1 day ago* (last edited 1 day ago) (2 children)

No, no, no, I am an econometrician, this Blair Fix person is an 'enthusiast of economics' who actually doesn't know how statistics or data modelling works.

Their whole blog post boils down to them not liking the format the graph is presented in.

I can assure you this a common way to visualize this kind of a data set.

When this Blair person presents their own 'test' later in the post, they are literally making shit up, they did not perform any test, they just generated random noise and then went 'see it kinda looks the same!'

Were they serious about this ... analysis approach, they would have compared their random noise to the actual dunning krueger data set and then done actual statistical tests to see if the dk set was statistically significantly different than a battery of say 1000 runs of their statistical noise generation, and to what extent it was.

They did not do this, at all.

They then cite papers from no name colleges no one has ever heard of that basically just argue that a histogram is 'the right way to present this', even though that completely destroys any visual concept of differentiating between where ones actual ability level is vs where one estimates it to be, that just flattens it to 'look at this psuedo normal distribution of how many people are wrong by how much', again with no reference to their actual competency level as a factor in to what degree they overestimate themselves.

You've fallen for a random shit poster who shit posts on a blog instead of tiktok or instagram or reddit or WSJ/WaPo Op-Eds.

You have been bamboozeled not by lies, not by damned lies, but by an idiot attempting to do statistics.

.........

If you wanted to maybe better visually portray the DK data, you coukd have the original graph, and then another graph, a bar graph, that shows the % difference between actual and perceived competency for each quartile.

And that would look like this:

(I am doing the digital equivalent of a napkin drawing here, from a phone, this is broadly accurate, but not precise.)

The lowest competency quartile believes they score at about 55th percentile when they actually score at about 10th percentile, so they overestimate themselves by about 450%.

2nd quartile; actual score is about 35 ptile, estimated score is 60 ptile, so they overestimate themselves by about 70%.

3rd quartile; actual score is about 60 ptile, estimated score is about 70 ptile, so they overestimate themselves by about 17%.

4th quartile; actual score is about 85 ptile, estimated score is about 70 ptile, so they overestimate_themselves by about negative 20%

So, there you go, you have a bar chart with 4 bars.

1st is 45 units tall,

2nd is 7,

3rd is 1.7,

4th is -2, going under the x axis.

collapsed inline media

Vertical height represents the magnitude of overestimation of a quartile's actual competency.

That is to say, the dumbest 25% of people think they are 4.5x more competent than they actually are, in terms of comparing themselves to all people broadly, whereas the smartest 25% of people actually think they are 0.8x as competent as they actually are.

This effect at the top quartile is roughly otherwise known as 'impostor syndrome', another thing that is well studied and definitely real.

But the main thing that should be visually striking from this kind of presentation is that dumb people, that bottom quartile, are literally in another order of magnitude of overestimating their abilities, they are in fact so wildly off that the rest of the graph is basically just noise around the x axis in comparison, they are in fact so stupid that they have no idea how stupid they are.

For a real world example case of this, go visit the Oval Office.

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[–] kbal@fedia.io 5 points 1 day ago

It's been demonstrated that it's mostly an illusion, and yet it's hard to escape the observation that many people who haven't studied it in detail understand the concept much less well than they think they do.

[–] Rhynoplaz@lemmy.world 5 points 1 day ago

I don't think it actually has.

I did a little digging on this, and there was one study that just threw some random numbers together and claimed it disproved it, but it doesn't seem to be widely regarded as a silver bullet to the DKE.

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[–] Bloomcole@lemmy.world 12 points 1 day ago (1 children)

Today?
It has been a fad for some time.
Ironically mostly used by people who think they're smart bcs they've heard of it.

[–] StupidBrotherInLaw@lemmy.world 5 points 23 hours ago* (last edited 23 hours ago)

Knowledge doesn't just diffuse into everyone's minds when it hits a fad threshold. There's still a point where one first learns about it. Shocking, I know.

[–] SpaceCowboy@lemmy.ca 12 points 1 day ago (3 children)

Isn't it more that people who are given a test will tend to think that the test was easy when they score well (when they actually scored well because they're an expert) and people will think a test is hard when they aren't familiar with the subject (nobody could've answered these question!) .

So it's more that experts and non-experts both assume their knowledge level is more average than it actually is. Not as fun as "dummies think they're smart and smarties think they're dumb." We all just tend to think we're average and most people are at a similar level of expertise to ourselves.

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[–] Juice@midwest.social 11 points 16 hours ago* (last edited 16 hours ago) (1 children)

Its at least partially a statistical trick. People of lower competence rate themselves closer to the middle, but people with high competence also do this.

I also find it hilarious how virtually everyone acts like an expert in diagnosing dunning-krueger. Like looking at a graph for a second and then repeating an academic mystification and 5-10 word snippet repeated ad nauseum is pretty fucking ironic given the subject

[–] Peruvian_Skies@sh.itjust.works 4 points 15 hours ago* (last edited 15 hours ago)

No no you see, because I have heard of the Dunning-Krüger effect on no fewer than two separate occasioms, I am a master at recognizing it in people no matter where they fall on its spectrum. You just don't understand because your overexposure to the concept has dulled your natural instincts, unlike me. /s

[–] CatDogL0ver@lemmy.world 9 points 1 day ago* (last edited 1 day ago) (1 children)

People with low competence fail to understand their limits, and people who are competent can identify theirs.

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[–] Aceticon@lemmy.dbzer0.com 8 points 1 day ago

As far as I can tell, we all have this, even people who are experts, it's just in different domains that those of their expertise.

[–] nomoretdrdd@lemmy.cafe 8 points 3 hours ago

It also work with the dunning Kruger effect itself. People who can't shut up about it are the one who don't understand it

[–] Cybersteel@lemmy.world 7 points 1 day ago (2 children)

I don't think DK is really about intelligence but more on how averages work. I don't know, I don't have a degree in statistics just a basic biochem one.

Don't discount yourself, I bet a lot of your education and research had to deal with statistics and deriving information from data. You're practically using statistics

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[–] Dasus@lemmy.world 5 points 1 day ago

Welcome to the internet

[–] mechoman444@lemmy.world 3 points 1 day ago

Lol flat earthers

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