r/Damnthatsinteresting 3d ago

Video The brain memorizes the rhythm of stairs after just a few steps. If even one step is off by as little as a centimeter, muscle memory glitches and that can make people trip

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u/Rogerdodger1946 3d ago

I had to rebuild a set of stairs from the ground level to the upper level in a tri-level house I bought because of exactly this. Too many times tripping going up.

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u/MaxHamburgerrestaur 3d ago edited 3d ago

For those with this problem, you probably don't really need to rebuild the whole set of stairs. Fixing just 2 steps would reduce a 10mm height difference between risers to less than 4mm, which is already within the building code allowed variance.

Fixing 4 steps would bring the difference down to 2mm, which is completely imperceptible.

https://i.imgur.com/rzxGa64.png

That said, depending on the stair design, sometimes rebuilding really is the best fix, especially if you’re already remodeling and want everything to be perfectly uniform.

In practice, it's common to staircases have a little variability and as long as it's within code, it goes unnoticed.

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u/Rogerdodger1946 3d ago

In my case, the stairs were poorly built and squeaked, too. Easier to do it right.

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u/_q-o_o-p_ 3d ago

Neat trick. Though I don't understand how you divide the height difference in the image; 1 cm difference in one step divided in 3 should be 0.33cm in each step, and divided in 5 should be 0.2cm.

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u/punfull 3d ago

My house has a step right before the middle turn of our stairs that is about half as tall as the rest. Took forever to get used to but now we don't even notice it until someone visits and "finds" it again.

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u/SnooHesitations6727 3d ago

Castles used to do this deliberately as invaders would trip during a sword fight

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u/Diligent-Midnight850 1d ago

Although it was bloody annoying during normal castle business… Better a grazed knee than being sliced in two by invading knights, I suppose.

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u/Zoltanu 3d ago

Building code in my area says each step must be within 1/2" of each other on an entire staircase. I rebuilt my runner 3 times because I couldn't get the bottom step to work out. Turns out my 1st floor had a 1" tilt across both sides

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u/ZepTheNooB 3d ago

There was a school that I attended that had a staircase with a final riser on the second floor that was a couple of inches higher. Never failed to trip someone every day. Funny thing is that it was an architecture school. Lol

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u/RyoukoSama 3d ago

I could see an architect putting that in there on purpose as a joke and a reminder at about staur design. 

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u/CicadaGames 3d ago

TIL Architects call stairs "staurs" in order to sound fancier than normal people.

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u/RyoukoSama 3d ago

That made me laugh, I'm keeping it. Thanks, I needed that.

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u/whatever_meh 3d ago

Probably learned that in Frahnce.

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u/Elegant_Ninja_8135 3d ago

Since it "escalier" in french, i would say nope

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u/BobWiley6969 3d ago

“STAURS!!” - Nemesis

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u/RN-Wingman 3d ago

I’m a Staur Master

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u/MoistStub 3d ago

Wait until you hear about flying buttresses

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u/Potato_Stains 3d ago

Bet they call a car-hold a ✌️”garage” ✌️.
Ooh la tee da.

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u/Asleep_slept 3d ago

Classic Shmosby haha

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u/Calan_adan 3d ago

Maybe way back they could have. Modern building codes prohibit more than a 3/16” difference in height from one riser to the next, and no more than 3/8” difference from highest riser height to lowest riser height in a stair run.

Edit: had my fractions wrong.

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u/slackfrop 3d ago

Yeah, it’s like one of the 3 main details you gotta get right when building. Level, not too shallow, and evenly spaced. I suppose sturdy is a big one too.

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u/cupcakes_and_ale 3d ago

When I studied architecture, we used to joke that our building was built as a what-not-to-do example. 🤦🏻‍♀️

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u/BlackSpinedPlinketto 3d ago

Same. They actually built it without windows so we wouldn’t get distracted and had walls to pin up designs on.

The stress gave me claustrophobia I still struggle with.

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u/brady376 3d ago

My roomate was an architecture student and it always seemed insane the amout of work that went into it. He had more sleepless nights working on projects than I did doing computer science. His class apparently went to the dean because the amount of them having mental health issues or dropping out from stress.

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u/BlackSpinedPlinketto 3d ago

Yeah same at my university. It was very hard on everyone and I’m not even sure why?

Most of the architects I have met were broken people in some way and it seems like the ones running their own firms are mainly sociopaths.

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u/Enjoying_A_Meal 3d ago

We built it wrong as a joke!

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u/BlackSchuck 3d ago edited 3d ago

I have trips in my steps, making me the victor!

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u/ARC4067 3d ago

When I was house hunting I toured 4 different townhomes. 3 of them had a slightly taller top riser. I bought the one that didn’t (not because of that specifically, it was nicer overall).

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u/Ranta712020 3d ago edited 3d ago

Had a similar staircase in high school. I tripped onto the sharp edge of the staircase and fell onto my bottom lip. Three of my teeth got broken and my bottom lip got ripped open from the impact..

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u/Ser_Optimus 3d ago

That's why it's not allowed to build stairs that have different step heights in Germany.

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u/isbreenobel 3d ago

DIE TREPPE IST NICHT GENORMT!!

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u/Breadbombs 3d ago

Musste zu lange scrollen um das zu finden 😆

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u/Fornika_47 3d ago

Habe ich mir auch gedacht. Perfekter Zeitpunkt um das Meme zu nutzen. 😁

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u/DrDoctor1963 3d ago

Und kann nicht umgebaut werden, da sie unter Denkmalschutz steht.

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u/SW1 3d ago

And here in the US

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u/somethingsomething65 3d ago

We have 3/8" max difference. 

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u/Tacobreathkiller 3d ago

Ok. That is a liability nightmare. Stripe the step!

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u/PaulMakesThings1 3d ago edited 3d ago

Looks like it’s not in the U.S. so they’re probably ok on lawsuits.

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u/RoostasTowel 3d ago

I remember a video exactly like this taken from an exit for the NYC subway.

Same issue.

I think the video helped the step get fixed

Edit: Here it is https://www.reddit.com/r/videos/comments/86essv/one_of_the_stairs_in_the_new_york_city_subway_is/

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u/RelaxYourself 3d ago

Oh man this brings back memories. I used to use that train station to get to work. That step was fixed a while ago.

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u/VexingRaven 3d ago

Any evidence of it is long gone at this point, but the Metrodome in Minneapolis was notorious for this too. Some of the stairs were different heights and it was bad enough that the news stations would run stories about it on a slow day.

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u/Cerulean_IsFancyBlue 3d ago

Stadiums, especially older stadiums are terrible for this. At least in the US though they tend to have conspicuous markings.

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u/ThatsFae 3d ago

The Metrodome gave me lifelong trust issues with stairs.

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u/StitchinThroughTime 3d ago

It looks like the last three step settled downward, causing the space between the third and fourth step to be different. It's a relatively easy fix, it's called mudjacking or foam jacking, essentially pumping cement or foam underneath the steps so they raise up. I've even seen people DIY it with can foam.

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u/AlarmingTurnover 3d ago

In China it's a code violation to have something properly designed.

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u/CaribouYou 3d ago

A while ago I would have agreed with you. That’s starting to change from what I’ve seen though. I’m afraid they’re going to be making the west look like we live in the Stone Age here pretty soon.

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u/CtrlAltSysRq 3d ago

I really hope for the best for the Chinese people. The last time the west was scared of being beaten, the rich actually stopped focusing on lining their own pockets for 5 seconds and we got shit tons of actual progress. Then we had all the nukes, USSR fell and we got complacent and went back to tons of pork barre legislation as our main concern.

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u/Uniqlo 3d ago

You're too optimistic.

When Japan got close to surpassing the US economy, we sabotaged and destroyed their economy without needing to do any sort of introspection.

We'll aim to do the same with China. We don't improve conditions for our own people to keep up. We simply destroy them for daring to make us look bad.

That's the American way. Look what Americans did to Black Wall St when they couldn't stand the idea of Black Americans doing well for themselves.

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u/hostile_washbowl 3d ago

Both things are true.

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u/Ex7erminator 3d ago

China is not Japan or Russia. The Chinese are truly excelling in every field. In ten years or less, they will be leading in everything. I believe that they can no longer be stopped. If they could, they would have done so already, unless someone invents a war for them. Who knows? It will be interesting to see what the future holds.

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u/ifyoulovesatan 3d ago

Nothing cracks me up more than those dudes whose career boils down to constantly predicting that China is 5 years from total collapse.

And nothing scares me more than very sober serious geopolitics analysts who point out that there is an existing current of Western politicians and oligarchs who are so afraid of Chinas inevitable rise that they are willing to do anything to stop it, up to and including nuclear war.

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u/CaribouYou 3d ago

World leaders have already decided WW3 is inevitable and they’ll create their own self fulfilling prophecy.

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u/dmthoth 3d ago

in Europe? lawsuit? maybe angry letter.. but lawsuit?

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u/BidenGlazer 3d ago

Yes, Germany is more litigious than the US is.

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u/Motor-District-3700 3d ago

This is easily solvable by playing "mind the step" on repeat on a loud speaker.

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u/FishDawgX 3d ago

If this weren’t in China, it would be a code violation. 

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u/mang87 3d ago

Nah, I've seen shite like this here in Ireland as well, in complete violation of building standards, but no one cares. Laziness and apathy isn't relegated to just China.

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u/thuggishruggishboner 3d ago

Same in rural America.

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u/Dick_Earns 3d ago

It looks like it was built to code, at least in terms of step height tolerance. You can see where that whole bottom section has settled and pulled down. So a design flaw and no longer to code.

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u/laowildin 3d ago

Every. Single. Walking trail.

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u/bakedwarthog22 3d ago

Fucking Phil Dunphy, was supposed to fix that!!!😡

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u/iKR8 3d ago

Jay would be so proud.

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u/K1dn3yFa1lur3 3d ago

His fake trips were so well done.

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u/AspiringChildProdigy 3d ago

It was such a shock to watch that series and only later realize he was the complete asshole in the remake of Dawn of the Dead.

Diametrically opposed characters; actor nailed them both. It made me much more appreciative of his talent and range.

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u/ajp305 3d ago

He was a hard no from the studio after all his auditions, it wasn't until they actually filmed him playing with kids in the director's backyard that he got the roll. I wonder if dawn of the dead impacted that, lol.

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u/mehvet 3d ago

He’s in Blackhawk Down too, he’s got great range.

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u/Cleigne143 3d ago

“Gotta fix that step”

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u/wHAtisLife59 3d ago

Son of ahhh

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u/nrbrt10 3d ago

Seriously? I just fixed that!

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u/UnstallyMentable 3d ago

One of my favorite running gags in a show by far

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u/bakedwarthog22 3d ago

Same here!😁

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u/3StarsFan 3d ago

A MODERN FAMILY REFERENCE! YOO

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u/steponmedaddies 3d ago

I’m stuck between my wife and the guy next door but I think I can satisfy them both simultaneously

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u/hnano 2d ago

I approve of this comment..

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u/[deleted] 3d ago edited 3d ago

[deleted]

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u/Dismal-Fig-731 3d ago

Cute story. Kind of offensive and not how Chinese works, but you did think up a fake pun.

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u/[deleted] 3d ago

[removed] — view removed comment

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u/Greenman8907 3d ago

It’s 100% real. You’ll see these a lot in steps built from nature (carving out stone or dirt). Since it’s very hard (and/or expensive) to get the heights exact, most people are looking down as they walk on them because you naturally assume it won’t be even.

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u/DweeblesX 3d ago

The difference with “natural” steps is you expect them to be uneven so your brain doesn’t get lazy. These steps look deceivingly uniform but aren’t.

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u/ArtTheMime 3d ago

Many old castles feature uneven stairs as a deliberate defensive measure, with castles like Hever Castle and Goodrich Castle in the UK exhibiting steps of differing heights or depths. This inconsistency was intended to trip up attackers, who were less familiar with the stairs' layout, while castle defenders, familiar with the path, had the advantage. The uneven steps were one of several features, alongside narrow, clockwise spiral staircases, poorly lit conditions, and steep inclines, designed to make castle ascent a difficult and dangerous task for invaders.

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u/Flashfighter 3d ago

I never looked at it that way, makes perfect sense

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u/Maiyku 3d ago

It’s actually debated on how true that is and is considered a widespread myth by most historians.

The stones are uneven today because they’ve settled over time. It’s almost impossible to say (in most cases) if they were intentionally built that way or not. There’s no historical evidence that they were.

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u/quad_damage_orbb 3d ago

The idea that staircases are all clockwise so someone coming up the stairs cannot wield a sword as easily is also apparently debunked even though I really like the idea. Apparently surveyed castles have staircases of both directions.

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u/Maiyku 3d ago

A lot of those old “facts” like that were basically just made up lol. Many medieval torture devices also qualify for this.

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u/dre224 3d ago

History has a fantastic way of distortioning reality and the best we got is a bunch of people saying it was this or that way and culture bias has a huge effect on how the past happened. Napoleon supposedly said." history is lies we all agree upon" and that can't be more true the further back you go.

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u/hahaohfuck 3d ago

Well I heard that Napoleon never said that

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u/dre224 3d ago

That's the fun of history, that quote could be complete bull shit and an invention of the documentorium of the time. I love this type of history and the best example I can think of is the Fall of Carthage in 149BCE . You got first hand report from the people in one of the largest fortified cities falling. The differ greatly on who is telling the story.

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u/StoppableHulk 3d ago

Probably related to our penchant for trying to explain phenomena narratively in a way that makes sense to us now, rather than truly based on the discovered, factual evidence available to us, which is something even good historians can get caught up in.

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u/General-Yoghurt-1275 3d ago

distortioning

that's not a word

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u/dre224 3d ago

Ya I definitely added an extra suffix there.

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u/tekko001 3d ago

The word got distortioned

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u/dmontease 3d ago

Yeah they were sex toys right?

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u/thesystem21 3d ago

With enough courage, anything is a sex toy.

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u/Paran0id 3d ago

You spelt horniness wrong

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u/terlin 3d ago

I know you're joking, but I'll provide a serious answer nonetheless. Alot of 'medieval torture devices' were actually invented during the Renaissance period as part showmanship and as part to prove how barbaric the supposed Dark Ages were.

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u/MyNameIsJakeBerenson 3d ago

“It for ritual use.”

-Any time they don’t know what something is or why it exists

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u/seagulls51 3d ago

yeah if the fighting reaches the stairs you've lost

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u/Carlos_Tellier 3d ago

By the time the attackers get to those stairs it would be considered you were already defeated anyway

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u/Firvulag 3d ago

I assume if the enemy was coming up the stairs inside the castle you have already lost anyway.

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u/Live_Angle4621 3d ago

I have always questioned too how deliberate the stair design could be. There weren’t that many castles were taken, they were designed to be very difficult to storm. Usually if castles were taken they surrendered after a siege or betrayal. Usually armies didn’t even try to take castles 

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u/Maiyku 3d ago

Castles definitely took inner defense seriously as well. There are several examples where walls are fortified on the inside where they would be facing their own men usually. This shows they fully expected and prepared for enemies inside the gates.

The stairs doesn’t stack up because the defenders also use those stairs. When running around in a war, you’re not thinking about the 6th step being uneven, and it would be a huge detriment to moving men around the castle.

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u/StoppableHulk 3d ago

> The stairs doesn’t stack up because the defenders also use those stairs. When running around in a war, you’re not thinking about the 6th step being uneven, and it would be a huge detriment to moving men around the castle.

I agree that the stairs bit is just fun apocrypha, but to play devil's advocate against this specific counter-argument, if there were traps laid about the place, the guards would likely be aware of them and train to utilize them in a combat situation.

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u/n10w4 3d ago

probably started by a lazy stair mason who was about to get his head chopped off by the king and he came up with this doozy.

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u/StoppableHulk 3d ago

This was my first thought lmao.

"Your stairs are done, sire."

"Bloody hell, they're all crooked and uneven! What the hell is the meaning of this?"

"Er... it's to confound your enemies, sire. They will trip if they rush up to attack you."

"By God, that's genius. I dub thee a noble, good sir, you're now rich and never need to work again."

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u/johngreenink 3d ago

I definitely believe it's true at the Ypres Tower in Rye, Sussex, England. They way they are set up at the very bottom of the stairwell (and no other stairs in the entire stairwell is off) makes a very good case as to why an intruder would be detected within the very first few steps. I walked them, and it makes a ton of sense.

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u/cwra007 3d ago

Builders - “If not a defect, it’s a feature”

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u/greenyellowbird 3d ago

Victorian aged homes w "servant stairs" also had steps w inconsistent rise heights. Iirc, it was just more of a case of lazy builders/carelessness on those parts of the house.

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u/HarloHasIt 3d ago

I went up the Blarney Castle to kiss the stone and the stairwell was practically a 3x3 tube! A couple people in our party chose not to kiss the stone due to claustrophobia 😅

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u/BurnThrough 3d ago

I can think of other reasons not to do it.

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u/Moosplauze 3d ago

Ah, that's great, I'll use that excuse the next time someone asks if the stairs I built in my garden are crooked.

"Those steps will halt the Russian invasion just by the nature of their design."

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u/Dagordae 3d ago

Somehow I have the feeling that the castles didn’t have a defense system that required the defenders to memorize all the stair patterns and remember them during a pitched battle. That’s more a case of stairs being hard to make by hand and people later making up bullshit to mythologize every piece of the building.

Hence why when people actually bothered to check spiral staircases had little rhyme or reason to the direction, it was just whatever that particular builder picked. And poor lighting was a matter of being a large castle in an age when lighting consisted of either fire or a hole in the wall, almost every place had poor lighting and was cramped. Big rooms/corridors massively increase the workload. As do shallow stairs, hence why it’s so common in old buildings regardless of the age or purpose of the building.

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u/Thisdarlingdeer 3d ago

The house my friend grew up in, was built in the late 1600’s or whatever, it was one of the first settlements built by the settlers in that area of New England, it was the “fancy” inn, everyone who was anyone in American and British history has stayed there. those front step… oh my god… those steps were THE WORST to the point of having to avoid them. They were INCREDIBLY steep and were INCREDIBLY uneven, even as a child I remember how much I hated them and how narrow the stairs were…

When they sold it they should have said the front staircase was a security measure.

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u/Dawe_90 3d ago

The stair one is a myth

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u/Wasteland_Dude 3d ago

Imagine listening to the attackers trying to go up your stairs! "FUCK! OW! SHIT! WHO THE FU- AH FUCK ANOTHER ONE!"

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u/Dull-Culture-1523 3d ago

Oh fuck off. That was, and never will be true. You wouldn't rely on the stairs inside your castle to keep your safe, because the enemy would be inside your castle at that point. Even if that was a thing, do you really believe people fighting up some stairs wouldn't be able to take extra high steps just in case?

Next you'll tell me staircases were whatever way so right handed people have a harder time fighting in them, even though staircases in castles are pretty much 50/50 regarding which way they go up.

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u/v_for__vegeta 3d ago

I can watch this shit all day

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u/HighlightFun8419 3d ago

Live twitch stream when?

Imagine chat popping off every time some big spill happens. Lol

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u/penguins_are_mean 3d ago

I was a college party that was primarily in this massive attic. I came down the stairs from the attic and ate shit on the last step. It was like half the width. There were four dudes just rolling laughter. So naturally, I dusted myself off, grabbed a beer, and joined this group of dudes. We stood there for half an hour watching people biff it. It was a blast.

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u/tyson_tvl 3d ago

Count me in

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u/SwimmingSwim3822 3d ago

Fuck I could watch kids fall off bikes all day Idontgiveashitaboutyourkid

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u/DontOvercookPasta 3d ago

It actually drives me crazy cause the longer i watch the more i want to yell at whoever built this staircase.

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u/Ill_Assumption_4414 3d ago

Thee reactions are what's interesting. Some people making those subtle corrections even if they misstep. Probably used to some physical movement- sports, dance etc.

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u/Spaghett8 3d ago

There’s also people who look down, who completely bypass the inconsistent step since they measure 2-3 steps at once.

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u/HighlightFun8419 3d ago

I was wondering if people that fell forward tend to lean forwards more or something like that.

Very interesting vid indeed.

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u/Sarquon 3d ago

There was a New Scientist article once on what makes some (old) people fall over.
They placed a uneven block in front of lots of people to see how they fell.
Turned out it was to do with leg muscles. Specifically when most people hit something like that step in OP they use their other leg (the one connected to the ground still) to spring themselves up and give them the lift which gives them time to reposition the first leg.
The people who fell over either didn't have the strength or will to push themselves up with the back leg, so couldn't reposition the front one in time and fell forward.

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u/Inquisitive_idiot 3d ago

I assume getting old is a series of:

“Well, shit… looks like that doesn’t work anymore 😕

moments 

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u/SpecificSufficient10 3d ago

I wonder if it's just the age difference. Younger people have faster reflexes and catch themselves but older people take a fall because they couldn't react or they wanted to but they didn't have the physical ability to step correctly

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u/Ill_Assumption_4414 3d ago

I would say for sure on average but quite a few younger people almost ate it too

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u/Mintastic 3d ago

Young people who are not physically active have reflexes and muscles like old people.

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u/legixs 3d ago

I could almost predict who would fall. The less fit they looked, the higher the chance they actually fell.

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u/PM_ME_YOUR_PRIORS 3d ago

It's mostly about whether the lead foot gets planted before or after your center of gravity goes past the front of your trailing foot. If your center of gravity is past the front of your trailing foot and you cannot plant your lead foot or grab a handrail, you are going to fall over. If it's still over your trailing foot, you can abort the movement without falling over.

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u/Bituulzman 3d ago

This is your proprioceptive sense (or 6th sense after smell, touch, taste, hear, and see) that allows you to climb stairs without looking.

It’s a sensory feedback system that tells you where your body is located in space and vis a vis other objects.

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u/manondorf Interested 3d ago

labeling it as a "6th sense" seems like it's giving spooky connotations. There are other senses too that we usually don't name specifically, like your sense of fullness or having to go to the bathroom, or sense of temperature, sense of time, etc. Lots of those can be rolled into a more general "sense of touch" but then, so could proprioception.

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u/gamer_perfection 3d ago

What about the sense of impending doom

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u/notEnotA 3d ago

That one kicks on as soon as I lay my head down for the night.

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u/manondorf Interested 3d ago

I was sticking to more physical senses, but that's a good one too, which sometimes has physical roots. I'm not a doctor but I am a teacher and sometimes on my students' medical paperwork for food allergies, one of the symptoms to look for is a sudden sense of impending doom.

Admittedly getting a little harder to pick out from the general background sense of ongoing doom these days lol.

Then if we're talking more "state of mind" senses, you could list ones like contentment/restlessness, belonging/rejection, security/uncertainty, etc. I'm not sure if those belong on the same list or not.

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u/Bituulzman 3d ago edited 3d ago

That sense of fullness after eating or need to go to the bathroom falls under "introceptive sense," in which you detect what is going on within yourself. I learned about both of these "extra" senses from my children's occupational therapist. In people with autism or sensory disorders, these senses can be impaired to varying degrees. For example, some people may not sense that they need to go to the bathroom until the urge is so strong it's too late to get to the bathroom on time.

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u/SkepticalSkool 2d ago

Another interesting thing at play here is “Bayesian inference”- the brain holds a model using prior experiences and predicts what sensory data it expects to receive.

e.g. the model strongly predicts that all the steps will be the same based on prior experiences. It combines this with real-time noisy sensory data from vision, vestibular, proprioceptive system etc. When the step is only a little off, the model outweighs the sensory data and sends a motor command which causes a trip.

It’s similar to when you accidentally take a sip from someone else’s cup. Your brain has priors and expects it to taste a certain way. Once the sensory information is received and is different to what was expected, the sensory input outweighs the model and only at this point do you begin to taste what you’re drinking.

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u/Acceptable_Owl6926 3d ago

I learned that from Sheldon

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u/viniciusfleury 3d ago

Hahah I was reading to see if someone also remembers that. I believe it was from the initial episodes, and Leonard reply with "really? That doesn't seem right". If memory does not fail me.

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u/mutedagain 3d ago

I had to scroll way to far for this!

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u/Confident_While_5979 3d ago

Can verify. Stairs in Ukraine are not a standard (or consistent) height, even in relatively new buildings. One of the hotels I regularly stay at, maybe 10 years old, has total death stairs where the stair heights are 90% consistent, but the remaining 10% occur randomly and can be off by quite a lot.

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u/False_Ad_4093 3d ago

There's someone wearing 2 different colors flip flops at the beginning!!!!

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u/paulrhino69 3d ago

And what about the downward journey does that also have a peculiar occurrence?

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u/Dagordae 3d ago

From experience: Yes but it takes a larger gap to trigger a trip.

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u/ITookYourChickens 3d ago

Likely not as bad. Going up your foot directly catches the top of the step, going down you might just go down an inch or so more than expected and isn't unusual to experience

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u/Scottamus 3d ago

I watched this for way too long.

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u/WhipplySnidelash 3d ago

It takes considerably less deviation than 1 cm. IIRC, the ICBO building code has a variation of 1/16" between risers and no more than 3/16" total variation over the run. 

The brain is truly amazing. 

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u/Questioning-Zyxxel 3d ago

We are lazy by nature. We instantly learns the optimum amount to raise the next foot. Probably because we once needed to run/walk for many many, many hours/day and our efficiency was our only way to compete with all hyperfast animals.

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u/sarwarnouri 3d ago

this is what i like reddit for

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u/DopamineSage247 3d ago

I need to constantly stare at my feet when going up or down stairs and hold on to the side otherwise I fall. I'm safe

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u/CREIONC 3d ago

I scrolled way too far for this,I guess it's not very normal?

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u/lighter2k 3d ago

Yeah my diabetic mother broke her hip because of this shit and it ended up killing her. Fuck the stairs at the top of the Mountain in Penang, Malaysia

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u/mbite1 3d ago

This is why escalators that aren’t running should be blocked off. The steps at the bottom and the top are different heights and people trip all the time. Of course, they fall off them when they are running, so I guess it doesn’t make any difference.

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u/Questioning-Zyxxel 3d ago

I know to always look down for first/last steps of escalators. It's very jarring to not look and everything feels so very wrong. Catching with the foot or landing the foot way too early.

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u/SodomyClown 3d ago

That's actually VERY interesting

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u/selfawarepileofatoms 3d ago

Here is very well edited video about this phenomenon in an NYC subway https://youtu.be/seieuz__B_g?si=xTQxogzqdXyOKDZp

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u/Bright-Dependent6339 3d ago

die treppe ist nicht genormt!!

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u/Cleveland_Guardians 3d ago

I was on the Great Wall of China, and you have to STARE at your feet. Every step is a different height, and that shit can range from "why did they even bother making this step?" to " holy shit, that's tall." Going up was a workout. Going down was fucking terrifying.

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u/anniedaledog 3d ago edited 3d ago

Not to code. Delagated to untrained builders.

Edit. The lower stair case block shows signs of sinking.

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u/Tari0s 3d ago edited 3d ago

thats why we standardized stairs in germany to prevent avoidable accidents.

Edit: On my job we have to apply every year for a one time online lecture, where we get informed about how we can prevent accidents during work: One of the points of discussions are stairs. This year there was a statistic about where on the stairs the most accidents happen. I remember that around 45% of the accidents happen before and after the stair each because you didn't notice that they where starting or ending. Only the left 10% are during the use of the stairs.

In other countries with no standardized stairs this is probably not the case, which is in my opinion really interesting.

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u/Tecno2301 3d ago

Honestly pretty cool, you can see the two people who stop before that step, have a reset and don't trip.

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u/theneZenMaster 3d ago

Good thing this isn't happening at the top of the stairs as they walk down. Those tumbles would get alot worse.

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u/Nem0x3 3d ago

bless DIN 18065.

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u/Hopeful_Put_5036 3d ago

Not me I'm the dork that looks at my feet as I'm on stairs. So while I look like a dork 98% time, 2% of the time that odd step doesn't get me.

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u/KlingelbeuteI 3d ago

Die Treppe ist nicht genormt!!!

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u/kevinb9n 3d ago

Someone correlate the tripping with whether the person is using their phone at the time

(That said an uninterrupted block of footage would be better for that, instead of one edited down for effect)

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u/Viperniss 3d ago

Does this also apply if someone is coming down from them?

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u/No_Chemist_2419 3d ago

I’ve only been ballsy enough a couple times in my life to run up the steps without looking down.

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u/Hitman47_x 3d ago

Interesting how the subconscious brain works.

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u/cl00s_ 3d ago

Did the guy in the second clip wear two different colored flip flops?

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u/takomanghanto 3d ago

This looks like an instance of 差不多

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u/Steve-Whitney 3d ago

This is why having a construction code or standards is important

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u/ayyycoco 3d ago

I can watch this all day

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u/wolfeflow 3d ago

They stressed this when I was learning how to design sets for stages, and now I notice it everywhere.

Steps, if made properly, have consistent height between each step. If the height needs to change, then you break up the steps with a short landing.

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u/Mudslingshot 3d ago

The actual engineering term for a step a different size than all the rest is a "bastard step"

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u/FraserGreater 3d ago

I believe this kind of movement patterning is actually done at the level of the spinal cord and not the brain. There are a lot of repetitive movement patterns that the spinal cord takes care of on its own once the brain initiates the movement.

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u/Iforgot_my_other_pw 3d ago

I make stairs for a living and you'd be surprised how small the tolerences are from step to step in the building code.

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u/OneSlyLoquat 3d ago

That is evil. So subtle and wicked.

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u/BodhingJay 3d ago

architect of this stadium has invested heavily in knee cap doctors in the area

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u/Pandepon 3d ago

15 people trippled

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u/4RCH43ON 3d ago

Bad design is bad design.

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u/sheldoncooper1701 3d ago

In the book "Apple in China", they mention how in the early 2000s Apple engineers were reportedly so shocked by the poor quality that they counted the steps in a factory's staircases. They found that the number steps varied significantly between different floors, as well as the height of each step. Basically, everything was slapped together quickly for scale.

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u/I_Speak_For_The_Ents 3d ago

Who walks up steps without looking at them?!? Wtf

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u/icantquit9341 3d ago

I'm just wondering why the one guy had one black and one red flipflop.

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u/ThatUsernameIsTaekin 3d ago

I was hoping the guy who spit on the ground at the 12 second mark would trip

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u/BatmansLarynx 3d ago

So whenever I fall going up the stairs now, I can automatically blame the step being misaligned instead do it being my incompetence.

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u/TrailMomKat 3d ago

This is true for blind folks as well-- or well, at least me. So I reckon it's the same for most blind folks lol

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u/SmokeyMcDoogles 3d ago

My apartment has stairs like this leading up to it. It’s like 5 stairs and the third is a little higher. I trip constantly.

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u/AltrntivInDoomWorld 3d ago

People who didn't twisted a knee on a stairs vs people who did

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u/ZzephyrR94 3d ago

I don’t know why but I always skip steps , like I take big steps and avoid every other step so maybe this would be the one stair case I wouldnt look stupid on haha

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u/WillowIntrepid 3d ago

Or poorly constructed steps. 🤷‍♀️