# Nerdy Geniuses Share The Most Interesting Mathematical Facts In Their Brains

### Nerdy Geniuses Share The Most Interesting Mathematical Facts In Their Brains

# Math Nerds, unite!

Chances are if you ask the average person about a math fact, the best they'll be able to come up with is "2+2=4." But not these Redditors. We all know math has to have some cool, complicated concepts, but how could we ever understand them?

Reddit user xxTick asked the masses:

Here are some answers that will make you reconsider those days you skipped intro to calc.

### E, Eh?

e (2.718281828459045...) is the average number of random numbers between 0 and 1 that must be added to sum to at least 1.

### Excitable Numbers

there are exactly 10! seconds in six weeks.

10! = 1 x 2 x 3 x 4 x 5 x 6 x 7 x 8 x 9 x 10 how many seconds in 6 weeks? 6 weeks x 7 days x 24 hours x 60 minutes x 60 seconds = (2 x 3) x 7 x ( 2 x 3 x 4) x (2 x 3 x 10) x (5 x 6 x 2) combine the 3's, combine the extra 2's, stick a 1 in front... = 1 x 2 x 3 x 4 x 5 x 6 x 7 x 8 x 9 x 10 seconds.

### Classically Trained

Cantor's diagonal proof which implies more than one infinity. At least for classical mathematicians.

### And Beyond

Gabriel's horn, the volume of the cone is finite, but the surface area is infinite.

### Rumors Spread

As a PhD student in mathematics, this is not a sexy answer, but one of the reasons I fell in love with math was in my differential equations course when we discussed modeling epidemic using mathematical equations. It was so incredible to me that back in 1927, Kermack and McKendrick came up with a simple formulation of how to model a disease. This idea has been expanded greatly, but their original version of the S-I-R compartmental model is still one of the coolest things. And it can also model rumors as well!

### Unsatisfied

I love Fermat's Last Theorem:

no three positive integers a, b, and c satisfy the equation an + bn = cn for any integer value of n greater than 2.

It just intuitively seems that some n should work, given infinite possible numbers, but it's been proven that nothing but 2 fits.

### 2D Life

If you take enough random steps in two dimensions, you'll always eventually get back to your starting point. The same cannot be said of three dimensions.

I just find the idea that you will always get back to where you started by making random moves absolutely mind boggling, and the fact things change just because you can go up and down is even weirder.

### Imaginarium

ii = 0.20787957635

So an imaginary number to an imaginary power is a real number.

### Jokes For Days

99999999999999999989 is the largest prime number that can also be a Reddit username.

### Beep Booop Boop

1 x 1 = 1

11 x 11 = 121

111 x 111 = 12321

1111 x 1111 = 1234321

And on it goes

### Algorithm

The maximum number of moves needed to solve a Rubik's cube from any configuration is a mere 20.

Expecting Numberphile subscribers to have a strong showing in this thread.

### Belphegor's Prime

There is a prime number named after one of Satan's devils. It is a 1 followed by 13 0s. 666. 13 more 0s. And a 1.

### Conjecture Lecture, What's Your Texture?

The Collatz Conjecture: It's an unsolved mathmatical conjecture that can be summarized as follows; Take any positive integer, or "n". If n is even, divide it by 2 to get n / 2. If n is odd, multiply it by 3 and add 1 to obtain 3n + 1. Repeat the process indefinitely. The conjecture is that no matter what number you start with, you will always eventually reach 1. For example, start with 21. it's odd so I multiply by 3 and add 1, to get 64. 64 is even so I divide by 2 to get 32, again to get 16, 8, 4, 2, 1. No one has found a number that doesn't follow this rule.

### Birthday Drama

The Birthday Problem.

If you have 23 people in a room, there is a 50% chance that at least two of them have the same birthday. If you put 70 people in, the probability jumps to 99.9%.

It seems f-cking weird to me but I haven't done math since high school so what do I know.

### Impossible Parchment

if you fold a piece of paper 103 times, the thickness of it will be larger than the observable universe - 93 billion light-years

### The Ball

Banach-Tarski paradox, in a nutshell what it says is that if you take a (let's make it simpler) 3 dimensional ball, you can partition it in finite number of pieces (which is only true for 3-dim case, otherwise it's countably infinite) and then rotate and translate some of the pieces and you can get two exactly identical balls that we started with. So you might think we doubled the volume, indeed we did.

### It's Everywhere To Me

Astronomer here! Do you remember a few months ago when NASA announced the discovery of seven Earth-sized planets around a star called TRAPPIST-1? Astronomers and mathematicians freaked out a bit about it because it turned out all those planets were in resonance, where objects orbit in a simple multiplicative of another (so, if Earth were to orbit the sun one time every time Venus orbited twice- not really the case). These simple ratios can be good in celestial mechanics for sure- Pluto crosses Neptune's orbit, for example, but they are in a 2:3 resonance so will never crash into each other. But it's also very likely to lead to amplified gravitational forces that then eject planets, and frankly, TRAPPIST-1 should *not* be stable based on the resonances we see there and is just very luckily in a few million year gap or so where that system can exist according to mathematics and computer simulations.

The cool thing about this though is resonance is a mathematical concept that just describes vibrations, from that in a violin string to stability in a bridge. And acoustic resonance is *very* important for making music sound good- some resonances work, some make music sound "bad."

The cool thing here though is because mathematics shows up in *everything*, some Canadian astronomers realized you can "hear" TRAPPIST-1 because it has "good" resonances. (No really, they tried other systems, but apparently they all sounded awful.) They sped up the orbits of the system 212 million times (so you wouldn't have to wait ~18 years to hear the full piece), and frankly the resulting piece is pretty awesome. You should check it out!

Math is everywhere!

### Solitaire

One of my favorite is about the number of unique orders for cards in a standard 52 card deck.

I've seen a a really good explanation of how big 52! actually is.

Set a timer to count down 52! seconds (that's 8.0658x1067 seconds)

Stand on the equator, and take a step forward every billion years

When you've circled the earth once, take a drop of water from the Pacific Ocean, and keep going

When the Pacific Ocean is empty, lay a sheet of paper down, refill the ocean and carry on.

When your stack of paper reaches the sun, take a look at the timer.

The 3 left-most digits won't have changed. 8.063x1067 seconds left to go. You have to repeat the whole process 1000 times to get 1/3 of the way through that time. 5.385x1067 seconds left to go.

So to kill that time you try something else.

Shuffle a deck of cards, deal yourself 5 cards every billion years

Each time you get a royal flush, buy a lottery ticket

Each time that ticket wins the jackpot, throw a grain of sand in the grand canyon

When the grand canyon's full, take 1oz of rock off Mount Everest, empty the canyon and carry on.

When Everest has been levelled, check the timer.

There's barely any change. 5.364x1067 seconds left. You'd have to repeat this process 256 times to have run out the timer.

### The Bayes

Suppose a drug test is 99% sensitive and 99% specific. That is, the test will produce 99% true positive results for drug users and 99% true negative results for non-drug users. Suppose that 0.5% of people are users of the drug. If a randomly selected individual tests positive, what is the probability that he is a user?

The answer is around 33.2%

### Factorial Follies

69! (69 factorial; approximately 1.711224524×1098 ) is the largest factorial number that most hand-held calculators can handle. This is because it also happens to be the last factorial number that is less than a googol (10100 ), and these calculators can't handle numbers larger than a googol.

1729 is the smallest number that is the sum of two positive cubes in two different ways:

`1729 = 1^3 + 12^3 = 9^3 + 10^3`

### A Googolplex Of Text

Graham's number! Short version: it's really big. I'll try to explain how big, but you won't understand it. You literally can't. I'll explain that bit, too.

First, we need to understand iterative operations. We'll start with easy stuff, but we'll get to the fun stuff soon. First, a so-called "zero order" operation called the "sequence function." If you give it a number, it gives the next one. So if you give it a four, it gives a five. If you give it 283, it returns 284.

Now, the main first order operation is used as shorthand for how many times you want to do the sequence function. You can take a six, and say "start here, and do the sequence function four times." You'll end up with ten. You might recognize this as addition. 6+4 just means 6 -> 7 ->8 -> 9 -> 10.

Now, the second-order function is a way to compress a lot of addition. If you want to take six and add it until you have four sixes together, you write 6 x 4, which means 6 + 6 + 6 + 6. Multiplication, of course.

Exponentiation is just iterated multiplication: 64 just means four sixes, multipled: 6 x 6 x 6 x 6.

That's as far as most people need to know, but you can keep going. Tetration is iterated exponentiation. 6 tetrated by four means four sixes raised to each other: 6666. And 7 pentated by three means seven tetrated by seven tetrated by seven.

Now we're ready to begin. We're going to start with three sexated by three. That is, three pentated by three pentated by three, where three pentated by three equals three tetrated by three tetrated by three, and that tetration means 333 = 7.6 billion. So if you take 3333333... until you have 7.6 billion threes, you'll have three pentated by three. This number is incomprehensibly large. Trust me. Then if you pentate three by *that* number, you'll have three hexated by three. And *this* number is truly beyond the realm of human comprehension. But this number is not Graham's number. This number is called G(1).

Notice how each level of operations creates huge numbers far, far faster than even one level down. Sequentation is just counting. Addition gets bigger numbers a little faster. Multiplication with small numbers can get you into the hundreds quickly. Exponentiation very swiftly takes us into pretty big numbers, and tetration accelerates much faster than most real-world things ever call for. Remember how even just with two threes, tetration creates 7 billion.

Now, remember G(1)? What we're going to do now is take two threes, and the operation we're going to perform on them is a G(1)-order operation. Even one step up the operation orders makes a tremendous difference. Now we're taking a number of steps that is an unbelievable number. And when we're done, we have a number we'll call G(2).

Now keep going. Don't even begin to think of how big G(2) is. It's actually impossible. Just do a G(2)-order operation on two threes, and call it G(3). And then keep going. I'll skip to the end now: Graham's number is G(64).

I want to explain why I said you literally can't imagine it. I was not exaggerating. It's been proven, because numbers are information, and information has a fundamental relationship with entropy, and entropy with energy, and energy with mass. All that means that there is no way, even with quantum physics, to compute this number, in any fashion, without something that cannot exist.

Do you know the Planck length? The smallest measurable space that exists, the resolution size of reality. There are about 100000000000000 of them to cross the approximate diameter of a quark. Now imagine that every cubic space on Planck3 could be used to store one binary digit. One quark would have 10 with about 3000 zeroes of them, enough to store information about every atom in the solar system. But we don't need one quark. If we stored a bit on every cubic Planck length *in the known universe* we would still not have enough space to store Graham's number. You wouldn't even fit G(1). A complete computation of G(1) would literally destroy the universe.

That's what I love about Graham's number. We begin with numbers that without exaggeration are too big to fit in our reality, and then raise them to powers beyond comprehension. It's not nuclear overkill. It's cosmic scales of nuclear overkill repeated in terms no one can imagine, all before we've even really begun, and the power of words is exhausted. And yet... we can write it, in a recursive formula, on a sticky note of the palm of your hand in about thirty seconds.

Of course, it's not the biggest number. You could have Graham's number plus one. Graham's number times 2. G(65). G(Graham's number). But at that point, what difference does it make? If math is the language of the universe, what's the point of numbers the universe itself can never represent? Human language is the greatest limiting factor in human thought and communication, but human thought cannot keep pace with its own vision into the language of math.

Graham's number: for those times when someone's just learned Googolplex and you need to top them. Just make sure that guy's not in the room who knows about TREE functions.

### Bob Barker Or Monty Hall?

Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. He then says to you, "Do you want to pick door No. 2?" Is it to your advantage to switch your choice?

The answer is yes.

There are few things more satisfying than a crisp $20 bill. Well, maybe a crisp $100 bill.

But twenty big ones can get you pretty far nonetheless.

Whether it's tucked firmly in a birthday card, passing from hand to hand after a knee-jerk sports bet, or going toward a useful tool, the old twenty dollar bill has been used for countless purposes.

### Breaking Even

<p>"I got a jacket and a pair of jeans at goodwill for about $20. My first time wearing the jacket I found a tiny zipper inside a pocket."</p><p>"There was a secret inner pocket with a twenty in it."</p><p>-- <a href="https://www.reddit.com/r/AskReddit/comments/lvu5aq/whats_the_best_20_you_ever_spent/gpdv70q?utm_source=share&utm_medium=web2x&context=3" target="_blank">TheBrontosaurus</a></p>### Keeps On Giving

<p>"23 Years ago I was in the US for some work and was not prepared for the cold of Chicago. Went to wal-mart and bought myself a cheap, warm jacket."</p><p>"I'm wearing that jacket right now - still looks fine, still keeps me warm."</p><p>-- <a href="https://www.reddit.com/r/AskReddit/comments/lvu5aq/whats_the_best_20_you_ever_spent/gpe41xv?utm_source=share&utm_medium=web2x&context=3" target="_blank">TastyEnd</a></p>### As Good As They Come

<p>"Wool pinstripe double breasted suit from Goodwill, fit perfectly and was brand new. Ended up wearing it to get married the next year." -- <a href="https://www.reddit.com/r/AskReddit/comments/lvu5aq/whats_the_best_20_you_ever_spent/gpdw6mx?utm_source=share&utm_medium=web2x&context=3" target="_blank">verminiusrex</a></p><p style="margin-left: 20px;">"God I love Goodwill!!" -- <a href="https://www.reddit.com/r/AskReddit/comments/lvu5aq/whats_the_best_20_you_ever_spent/gpe5aee?utm_source=share&utm_medium=web2x&context=3" target="_blank">Neverthelilacqueen</a></p>### The Socks She Needed

<p>"I work at a thrift shop. A homeless lady came in and asked us where the socks were. We only sell new socks, so I directed her towards the new socks and she was... shocked and disappointed by the price tag, surely."<br></p><p>"I gave her a moment as she looked, and she moved to some kids' socks and picked them up, and I... just couldn't let that happen. I told her that I would help her, and told her to get herself some socks and a jacket."</p><p>"She kind of just... held out the children's socks, so I took them, put them back, and grabbed the extra fluffy socks that were hanging."</p><p>"She grabs a jacket and some pants, and I pay for it. My coworker looks the other way since we're not supposed to purchase anything while on the clock. The lady is in tears as she walks out."</p><p>"I notice that she's still outside a minute later putting them on, and ask her if they fit her or if she needed something else; and she told me they were perfect and proceeded to cry. I cried in return."</p><p>"It was a good day."</p><p>-- <a href="https://www.reddit.com/r/AskReddit/comments/lvu5aq/whats_the_best_20_you_ever_spent/gpen3w1?utm_source=share&utm_medium=web2x&context=3" target="_blank">Snowodin</a></p>### Not Forgotten

<p>"A guy came into my work when I managed a mom and pop Pizza Place. He said he was stranded with no phone, and no money, but that the people at the Verizon store next door to us said they could get him a cheap phone with some minutes on it for 20 bucks."</p><p>"He offered to do dishes for a few hours to make some money so he could get this phone. I told him not to worry about it and gave him a 20 from my wallet. He thanked me, asked me for my name, and then he left and I never saw him again."</p><p>"Skip forward about 5 months, and when I get into work the owner was there and said she had gotten a letter addressed to me. 'Weird,' I thought."</p><p>"But when I opened it there was a 50 dollar bill and a short note from the guy I gave 20 dollars to thanking me for my kindness and for not turning him away."</p><p>"Turns out he was in a bad way (addicted to hard drugs and homeless) and really was stranded there. He was trying to get a phone so he could contact his parents (who lived in another state) for help."</p><p>"From what it sounded like, he seemed to really turn his life around. He was clean and working a stable job while still living with his parents."</p><p>-- <a href="https://www.reddit.com/r/AskReddit/comments/lvu5aq/whats_the_best_20_you_ever_spent/gpem2xc?utm_source=share&utm_medium=web2x&context=3" target="_blank">Mixmaster-McGuire</a></p>### The Best Finale

<p>"It was the day before payday. My wife came to see me at work. My break was in an hour, so I asked for her to wait a bit, so we could enjoy it together. She did."</p><p>"I bought her some lunch, because it was what I could afford. I bought her a ham and cheese sub sandwich and two iced teas. These were her favorite. I bought gas with the rest of the twenty so she could get home. She dropped me back off at work."</p><p>"That night, she passed away. It brings me comfort to know that I bought her favorite sandwich and drink for her that afternoon. It was likely the last thing she ate, since it was near dinner. I'll never forget it. Best $20 I ever spent, because it was for her."</p><p>-- <a href="https://www.reddit.com/r/AskReddit/comments/lvu5aq/whats_the_best_20_you_ever_spent/gpe9c6d?utm_source=share&utm_medium=web2x&context=3" target="_blank">LollipopDreamscape</a></p>### Leaning Into the Nerdery

<p>"It was my ninth or tenth birthday. My grandparents gave me $20. The first $20 bill I ever held in my hand! I knew exactly what I wanted to do with it."</p><p>"A week later, we went into the city and Toys R Us. I went straight to the Transformers aisle. And there he was. My favourite Transformer. The one I always wanted...Soundwave."</p><p>"He's the one who turned into a Walkman and he could eject cassettes that turned into robot animals. The price tag said $19.99. It was meant to be."</p><p>"I took Soundwave to the clerk and gave her my $20 bill. "And here's your change!" she said, as she gave me a single penny."</p><p>"Ah, Soundwave. The best friend a lonely little nerd could have."</p><p>-- <a href="https://www.reddit.com/r/AskReddit/comments/lvu5aq/whats_the_best_20_you_ever_spent/gpdzzxe?utm_source=share&utm_medium=web2x&context=3" target="_blank">originalchaosinabox</a></p>### Different Time

<p>"I went to a Rush concert in 1982. The ticket was $9.50 and the t-shirt was $10." -- <a href="https://www.reddit.com/r/AskReddit/comments/lvu5aq/whats_the_best_20_you_ever_spent/gpdyr0k?utm_source=share&utm_medium=web2x&context=3" target="_blank">PaulsRedditUsername</a></p>### Motivational Spending

<p>"My then six year old niece had a loose tooth she loved to show off and had resisted pulling out for two weeks. We were all at my parents and I was getting ready to leave, I pulled out a $20 and said 'I'll give you this right now if you pull out your tooth.' "</p><p>"She was already crying because her little sister had did something so when she ran into the bathroom none of us had no idea in what she was about to do."</p><p>"So she comes out crying still, but a little bit of blood I'm her mouth because of course, she pulled out her tooth. But the now removed tooth fell down the drain to the sink and she was crying because she lost her proof!"</p><p>"After she calmed down she was happy as a clam with a brand new $20 and everyone was quite proud of her. My sister told me she spent it on candy and shared with her little sister."</p><p>-- <a href="https://www.reddit.com/r/AskReddit/comments/lvu5aq/whats_the_best_20_you_ever_spent/gpdxi4k?utm_source=share&utm_medium=web2x&context=3" target="_blank">themasimumdorkus</a></p>### For the Story

<p>"It was actually to a scammer in Rome. There was this guy right outside of Colosseum who started tying strings around my wrist and told me to make a wish. I knew it was going to cost but I thought what the hell, last day in Rome so might as well go with it. </p><p>"My wish was to find love."</p><p>"I spent rest of the day getting lost in the city and stumbled across two weddings and one baptism ceremony. So I did find love, just not for myself."</p><p>-- <a href="https://www.reddit.com/r/AskReddit/comments/lvu5aq/whats_the_best_20_you_ever_spent/gpe7b2w?utm_source=share&utm_medium=web2x&context=3" target="_blank">FatalFinn</a></p>I realize that school safety has been severely compromised and has been under dire scrutiny over the past decade and of course, it should be. And when I was a student, my safety was one of my greatest priorities but, some implemented rules under the guise of "safety" were and are... just plain ludicrous. Like who thinks up some of these ideas?

Redditor u/Animeking1108 wanted to discuss how the education system has ideas that sometimes are just more a pain in the butt than a daily enhancement... What was the dumbest rule your school enforced?### Don't Peek

<img lazy-loadable="true" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTcxNDc4OS9vcmlnaW4uZ2lmIiwiZXhwaXJlc19hdCI6MTYzNDE0Mzc2OH0.Y1Lzy1MTqxyVqOCe9xjeHTRZsKnbyVjYzdb4-Heldyo/img.gif?width=980" id="78b19" class="rm-shortcode" data-rm-shortcode-id="e14a90be026b734830e7661f776ba4a8" data-rm-shortcode-name="rebelmouse-image" data-width="475" data-height="475" />schitts creek wtf GIF by CBCGiphy<p>Took all the doors off the men's room bathroom stalls because of vandalism for 2 months.</p><p><a href="https://www.reddit.com/r/AskReddit/comments/lwjlif/what_was_the_dumbest_rule_your_school_enforced/gphrfce?utm_source=share&utm_medium=web2x&context=3" target="_blank"> Endless_Vanity</a><a href="https://www.reddit.com/user/Endless_Vanity/" target="_blank"></a></p>### Scanned

<p>School added thumb print scanners at gates of school which counted as registration - needless to say I would just walk to school scan my thumb and walk back home with them none the wiser. Was a great few months until they noticed. </p><p><a href="https://www.reddit.com/r/AskReddit/comments/lwjlif/what_was_the_dumbest_rule_your_school_enforced/gpidnou?utm_source=share&utm_medium=web2x&context=3" target="_blank">richpianofan5</a></p>### Age of Empires...

<p>Conservative Christian College. A group of us played Age of Empires one weekend. They didn't like it and called a meeting. Everyone involved got misdemeanors on their records. There was nothing in the handbook about it being against the rules. The only person that didn't get any punishment was the son of the president even though he was just as involved as the rest of us. <span></span></p>### "Genius"

<p>In my freshman year of high school we had a terrible vandalism problem, the bathrooms would be broken in various ways almost constantly. In a stroke of pure genius, the staff decided that any bathroom that was vandalized would be closed for the week on first offense, the quarter for second, and permanently on the third offense.</p><p>They took back the rule after closing every bathroom on day one. </p><p><a href="https://www.reddit.com/r/AskReddit/comments/lwjlif/what_was_the_dumbest_rule_your_school_enforced/gpi77co?utm_source=share&utm_medium=web2x&context=3" target="_blank"> Samus388</a><a href="https://www.reddit.com/user/Samus388/" target="_blank"></a></p>### Is this Footloose?

<img lazy-loadable="true" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTcxNDc5Ny9vcmlnaW4uZ2lmIiwiZXhwaXJlc19hdCI6MTYzMzg0MjU2M30.PeBUt-YWZeeRStaD_RZlGPQzo29E9t733yqZbIiJlYs/img.gif?width=980" id="3a5bd" class="rm-shortcode" data-rm-shortcode-id="102730e3b1b90ba9cb393561c702c9af" data-rm-shortcode-name="rebelmouse-image" data-width="500" data-height="500" />kevin bacon dancing GIF by STARZGiphy<p>Prom was a mandatory lockdown for the night in order to avoid students going to parties after prom.</p><p>Prom was held at various house parties across town instead. </p><p><a href="https://www.reddit.com/r/AskReddit/comments/lwjlif/what_was_the_dumbest_rule_your_school_enforced/gpi37x7?utm_source=share&utm_medium=web2x&context=3" target="_blank">Coffee-spree</a></p>### HOLDEN FOREVER!!!

<p>My high school mascot was Daniel Boone holding a musket. A kid wore a Guns 'n Roses shirt to school and was told he had to change shirts because of the pistols on the shirt. He pointed out the hypocrisy of the school mascot and they changed EVERYTHING. The mascot was switched to holding a flag pole instead. <span></span></p>### No Dots

<p>You couldn't wear ANY kind of head items that were "gang colours" (red or blue) - this No included hair bands, scrunchies, beads in your hair, ribbons - ANYTHING. I got in trouble for wearing a blue hair band with white polka dots. </p><p><span></span><a href="https://www.reddit.com/r/AskReddit/comments/lwjlif/what_was_the_dumbest_rule_your_school_enforced/gphzpyf?utm_source=share&utm_medium=web2x&context=3" target="_blank">Pleasant-Flamingo344</a></p>### Clothes Check

<p>We had to wear belts. Someone snitched that people weren't wearing belts under their sweaters, and they actually checked and a bunch of people got detentions. Stupid. </p><p><a href="https://www.reddit.com/r/AskReddit/comments/lwjlif/what_was_the_dumbest_rule_your_school_enforced/gphz3y6?utm_source=share&utm_medium=web2x&context=3" target="_blank">ooo-ooo-oooyea</a></p><p><a href="https://www.reddit.com/r/AskReddit/comments/lwjlif/what_was_the_dumbest_rule_your_school_enforced/gphz3y6?utm_source=share&utm_medium=web2x&context=3" target="_blank" rel="noopener noreferrer"></a>We had belt raids at my school where the dean would burst into classes, completely interrupting any education, to check that everyone was wearing a belt. </p><p><span></span><a href="https://www.reddit.com/r/AskReddit/comments/lwjlif/what_was_the_dumbest_rule_your_school_enforced/gpia8pp?utm_source=share&utm_medium=web2x&context=3" target="_blank">GuinnessMicrodose</a></p>### Chase the Flat

<p>We weren't allowed to play tag football at lunch, only frisbee. When I asked the principal what the difference was, he responded with a sarcastic tone, "A football is round and a frisbee is a flat disk."</p><p>He left the school later that year, went to another school, and a few years later was brought up on charges for failing to report the abuse of a student by a teacher. </p><p><a href="https://www.reddit.com/r/AskReddit/comments/lwjlif/what_was_the_dumbest_rule_your_school_enforced/gpi6lh3?utm_source=share&utm_medium=web2x&context=3" target="_blank">uninc4life2010</a></p>### Poke-Thief

<img lazy-loadable="true" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTcxNDgwMy9vcmlnaW4uZ2lmIiwiZXhwaXJlc19hdCI6MTY0ODg5MzY2Nn0.5LMPk1suou6U2SvAURKP-sHEuK7Izpkbxm0PWqvx95E/img.gif?width=980" id="b6e9f" class="rm-shortcode" data-rm-shortcode-id="92383d30e34aa92fd74cf6c1374ec294" data-rm-shortcode-name="rebelmouse-image" data-width="480" data-height="480" />hotline bling pokemon GIFGiphy<p>Pokemon cards got banned in middle school because someone stole the vice principal's kid's cards. Yep. </p><p><a href="https://www.reddit.com/r/AskReddit/comments/lwjlif/what_was_the_dumbest_rule_your_school_enforced/gpiapym?utm_source=share&utm_medium=web2x&context=3" target="_blank"> Skadoosh_it</a><a href="https://www.reddit.com/user/Skadoosh_it/" target="_blank"></a></p>### In the Face...

<p>If you were involved in a fight, you got suspended. While it sounds reasonable, context didn't matter.</p><p>I got suspended once not for throwing a single punch, kick, whatever. I got suspended because someone knocked the books out of my hand and when I reached down to grab them they punched me in the face.</p><p>I got suspended for walking down the hallway and unprovoked getting punched in the face.</p><p>Forget Brandon Valley Middle School. </p><p><a href="https://www.reddit.com/r/AskReddit/comments/lwjlif/what_was_the_dumbest_rule_your_school_enforced/gpicbyx?utm_source=share&utm_medium=web2x&context=3" target="_blank">CLG_MianBao</a></p>One of the golden rules of life? Doctors are merely human. They don't know everything and they make mistakes. That is why you always want to get another opinion. Things are constantly missed. That doesn't mean docs don't know what they're doing, they just aren't infallible. So make sure to ask questions, lots of them.

Redditor u/Gorgon_the_Dragon wanted to hear from doctors about why it is imperative we always get second and maybe third opinions by asking... Doctors of Reddit, what was the worse thing you've seen for a patient that another Doctor overlooked?### Grandma Wins

<img lazy-loadable="true" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTcxNDcxOC9vcmlnaW4uZ2lmIiwiZXhwaXJlc19hdCI6MTY0OTQxNTgzOX0.n9IaFGgHwnULMlI2kg7RUftxDg6lyWvdM9CnhvptCRY/img.gif?width=980" id="a0857" class="rm-shortcode" data-rm-shortcode-id="9762f97a23c27ccf6b75974caa854361" data-rm-shortcode-name="rebelmouse-image" data-width="480" data-height="270" />Old Lady Wine GIF by MattielGiphy<p>Not a doctor, but my grandmother saved my father's eyesight because she didn't listen to their doctor. </p>### The Mummy Appendage

<p>When I was a resident, an 80yo female was admitted from the nursing home for confusion. Workup showed some mild UTI and we were giving her antibiotics. The nurse mentioned that her toe looked dark and asked me to look at it. The toe wasn't just dark, it was mummified. It looked like dry beef jerky. I touched it and pieces flaked off. So the patient from a nursing home, had a mummified toe, probably for months, that no one knew about. </p><p><a href="https://www.reddit.com/r/AskReddit/comments/lw2g2z/doctors_of_reddit_what_was_the_worse_thing_youve/gpg00qn?utm_source=share&utm_medium=web2x&context=3" target="_blank">Dr2ray</a></p>### The CT Save

<p>Here's my story:</p><p>A guy came in to our ICU and was very septic but still talking. He had visited his primary care MD with complaints of a sore throat for a couple of days. Dismissed without any intervention since he didn't appear to have strep throat or the flu. At this point he was having pretty severe abdominal discomfort, so we sent him for a CT scan. As the scan was finishing, he coded and had to be intubated, multi-organ failure, etc. </p>### Patches

<p>When I was an ER nurse we got an elderly lady in for altered mental status from a nursing home, when we undressed her to put her in a gown and hook her up to the monitor, I noticed no less than 5 fentanyl patches on her, guess I discovered the cause of the AMS. </p><p><a href="https://www.reddit.com/r/AskReddit/comments/lw2g2z/doctors_of_reddit_what_was_the_worse_thing_youve/gpg1lml?utm_source=share&utm_medium=web2x&context=3" target="_blank">ChewbaccaSlim426</a></p>### Use your Words

<img lazy-loadable="true" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTcxNDcyMi9vcmlnaW4uZ2lmIiwiZXhwaXJlc19hdCI6MTY1MDA1NjI0MH0.WtyCdxL1vRZwD2-jpKZXMOEakwhiBaJIkp1YPnOzlvo/img.gif?width=980" id="e45ca" class="rm-shortcode" data-rm-shortcode-id="f5b98e6a4605a587dbd97579468a51d8" data-rm-shortcode-name="rebelmouse-image" data-width="498" data-height="367" />Communication GIF by memecandyGiphy<p>Neurologist sent patient to our ED without informing her that imaging showed a glioblastoma assuring her impending death. He didn't overlook the disease, he overlooked the communication. </p><p><a href="https://www.reddit.com/r/AskReddit/comments/lw2g2z/doctors_of_reddit_what_was_the_worse_thing_youve/gpfl5t5?utm_source=share&utm_medium=web2x&context=3" target="_blank">AzureSkye27</a></p>### Mad Cow Realty

<p>During my residency we had this lady in her 60s who was getting progressively more forgetful, just overall declining and getting less and less able to take care of herself. She had been seeing her pcp who diagnosed her with dementia. And she saw a neurologist who agreed. She was not really able to provide an accurate history. <span></span></p>### After Birth...

<p>I used to work in maternal-fetal medicine, and every single week, we would have women referred to us "because the doctor couldn't see something clearly with the baby and wanted to double check." Nope, they just didn't want to have to be the ones to tell you that your baby had a complex cardiac defect or multiple anomalies indicative of a genetic syndrome or any other of a large number of horrible things that can happen during fetal development. Still pisses me off when I think about how many women waited weeks for more information because their doctors were cowards who couldn't tell them, "There's something seriously wrong here." <span></span></p>### bad doctors

<p>I'm not a doctor, but a RN. This happened to me, but isn't nearly as bad as most of the stories on here.</p><p>When I was in college, I got to where I couldn't swallow. It started with difficulty swallowing, progressed to me having to swallow bites of food multiple times/regurgitating it, and then got to where all I could swallow was broths and mashed potatoes with no chunks. I went to the doctor multiple times, and was told every time it was acid reflux and part of my anxiety disorder. <span></span></p>### The Valve...

<p>He put the pacemaker lead in the subclavian artery (and across the aortic valve into the left ventricle). The proper approach is: subclavian vein to right ventricle). And then he didn't notice it for over a year. I saw the patient (a 25 yo woman who didn't need the pacemaker in the first place) when she was in congestive heart failure. <span></span><br></p>### Bitten

<p>Rattlesnake bite. On a 2 year old. Patient and dad out in the fields near a small town that is several hours away from the nearest big city, where I work.</p>When we think about learning history, our first thought is usually sitting in our high school history class (or AP World History class if you're a nerd like me) being bored out of our minds. Unless again, you're a huge freaking nerd like me. But I think we all have the memory of the moment where we realized learning about history was kinda cool. And they usually start from one weird fact.

Here are a few examples of turning points in learning about history, straight from the keyboards of the people at AskReddit.

U/Tynoa2 asked: What's your favourite historical fact?