Can you solve the famously difficult green-eyed logic puzzle? - Alex Gendler

Комментарии: 6 515

  • AShookKookie - 아숰쿠키
    AShookKookie - 아숰쿠키 День назад

    Bill and Carl has arms problem

  • Mizan Ahmed
    Mizan Ahmed 2 дня назад

    Wouldn't they already know at least one has green eyes since there is 100 percent chance they saw someone with green eyes? Why did the girl have to say anything?

    Edit: I get it now. They each know it, but they don't know the other people know what their eyes colour is without saying that

  • greencreepercreeps !!!
    greencreepercreeps !!! 3 дня назад

    What if they were colour blind .-.

  • caio marinello
    caio marinello 3 дня назад

    why they just dont desperately nod their heads or like make positive sign with their hands to each other

  • #AK thebest
    #AK thebest 4 дня назад +1

    They r 100 ppl cant they kill the dictator??

  • Dara Her
    Dara Her 4 дня назад

    Just look into the water out in the ocean .____.

  • RagingAsianGuy
    RagingAsianGuy 4 дня назад

    Cool but I think they can look through each other's eyes tho so yea

  • Aarvi Shah
    Aarvi Shah 4 дня назад

    This is on khan academy. Not the same, but similar.

  • usha rani nc
    usha rani nc 5 дней назад

    She could have said all of u have green eyes

  • berrybluee
    berrybluee 6 дней назад +1

    This one srsly got me thinking for 40 Minutes!!! The Concept with Two People is Ovbiously easy but from 3 People on it's a Mess around with "if i was Brown and what Would the Others think if they Were Brown Themselves Then as well (Then 3rd Person Would Know he's Green and Leave, yet he didnt, so If i actually was Brown, the Second Person Would now Know that he's Green since the 3rd guy didnt Leave the First Night and they Would Then Both Leave the 2nd Night, yet AGAIN they didnt so that means i MUST be Green - this Scenario playing of in ALL of Them, so Know all of them Leave the 3rd Night)
    Once that Concept is Understood on 3, it Takes another Perspektice more in regard (if i was Brown and he thought he was Brown too, Then 3 Would see Two Brown and he Would think he's Brown too, yet in the First Night 4 Doesnt Leave so 3 Knows he's Green and they Would Leave IF i was Brown, but they don't so now 2 Knows he's not Brown and IF me myself (1) was Brown theyd all Leave on Night 3 and so on)
    Super Complicated but Kind of Genius!

  • Yolo996
    Yolo996 8 дней назад

    So what happens when they spill the water?

  • heather lang
    heather lang 9 дней назад

    Darnass mountain I think really gorgeous video skin

    LEUNG WAI MING 9 дней назад

    I think every villages will know that everyone can see at least 98 green eyes in beginning, because if one village think he is not green eyes the other also will see 98 green eye than they will escape very soon

  • Xxzzertt
    Xxzzertt 9 дней назад

    You could say "Your neighbor has green eyes"

  • ArrowTheWolf
    ArrowTheWolf 12 дней назад

    Guess i'll be prisoner forever since i'm not that smart

  • I hate Jojo siwa
    I hate Jojo siwa 12 дней назад

    I could look for my eyes in the reflection of their eyes

  • Sofia Terrazas
    Sofia Terrazas 12 дней назад +1

    The prisoners could learn sign language??

  • xxtomxx
    xxtomxx 12 дней назад

    Spill the water on the floor and that will be their reflection. BOOM

  • Ellen Kim
    Ellen Kim 12 дней назад

    This riddle is making me stressed. Why couldn't they just look and stare deeply into each other's eyes to see that their eyes are green? I mean....

    KRYPTEC 13 дней назад

    "Everyone that all of you look at has green eyes" ez fix

  • hustleharder1000
    hustleharder1000 15 дней назад

    if the people on this island know what green eyes look like, does that not mean that any given individual would know that the other 99 have green eyes? If so then wouldn't at some point someone have made a comment along the lines of "Hey you have green eye, you can get out" which would eventually have a domino effect where every one would confirm that they all had green eyes?

  • Small Shell
    Small Shell 15 дней назад

    I think there is a simple solution.
    If I see that everyone around me has the same eye color and then is told that one of us had a different color; I would assume it was me.

  • Krine
    Krine 16 дней назад +1

    Can't you just look into someone else's eyes and see your eye color? Foolish mortals smh

  • iPhoneeditor
    iPhoneeditor 17 дней назад

    "The persons on your left and right have green eyes." Because everyone is on someone else's left or right they can now deduce they must also have green eyes.

  • Tracy Xu
    Tracy Xu 17 дней назад +1

    You can say "You can leave" Which TECHNICALLY can mean that that is an option, and not a statement. But, it's a statement. So wueva. They leave.

  • Tracy Xu
    Tracy Xu 17 дней назад +1

    Okayyyyyyyyyyyyy. So. Mhm. Got it. Dump the water out of the opaque water bottles. Im a genius.

  • Erica Joy
    Erica Joy 17 дней назад

    I think this one was completely flawed. The answer is not concrete. The statement leaves a lot up to assumptions. Not a sure fire answer

  • whatamigonnado
    whatamigonnado 18 дней назад

    Or just say give a thumbs up if you see green eyes the next morning

  • 2000sDigitalBoy
    2000sDigitalBoy 18 дней назад

    The answer to this riddle does make sense, but then what still confuses me is... Why does it matter that you tell the prisoners, "At least one of you has green eyes?" Isn't that something that they can plainly see for themselves each morning? Not only that, but can't they also deduce that every other prisoner has that same common knowledge?

  • TheDisguisedCreeper
    TheDisguisedCreeper 18 дней назад

    Answer:...they ask the dictator what there eye colors are

  • Juggernog B
    Juggernog B 18 дней назад +1

    Couldn't you just say: "everyone else has green eyes"? If addressed to everyone, they could all infer from this that everyone else perceived them as having green eyes, yet this injects no new info. Far simpler... But too simple? Plz tell me if I'm wrong

    JELLY GILLIAN!!!! Candy MONSTER 19 дней назад

    Why can't they just write down what they want to say ???

  • jakob hansen
    jakob hansen 19 дней назад

    umm i dont live on a island but does it not rain on them? then they look into the rain water see the eye color and leave
    and how would they know that if they will die if it isent the color if they dont comunicate and how would they understand her statment and how would they be extremly good at logic with out any comunication?!?!?!
    (sorry if my spelling is wrong im not english and im only 12 years old)

  • Daniel Kozintsev
    Daniel Kozintsev 20 дней назад

    The person on your right has green eyes.

  • Minnie Moouse
    Minnie Moouse 22 дня назад

    Me be like:
    Spill water on the floors

  • Adam Haris
    Adam Haris 22 дня назад

    After Thinking "long" and "hard"
    LOL XD 1:23

  • Arindom Paul
    Arindom Paul 22 дня назад

    Dude this doesn't make sense if you didn't have green eyes you wouldn't ever be let free soooooooo just take a guess

  • Brian Barker
    Brian Barker 22 дня назад

    This is actually really easy with many answers like... when you visit the island, you bring a Giant mirror, and asked the crowd, are you eyes green? and each person would see that they had green eyes, so did everybody else... on the first night... everybody leaves!

  • A. M. J.
    A. M. J. 22 дня назад

    Why isn't there time to figure it out for yourself on every video?!?!!
    Also, that one frame with the given information??
    Not cool.

  • BraiNarwhal: The Illogical Paradox
    BraiNarwhal: The Illogical Paradox 22 дня назад

    If I was one of the green-eyed people, and I saw them leave one by one, I'd just follow them because I am not a logician and I would've based them all in luck. Although, my luck is pretty moderate.

  • Dragon Huntress
    Dragon Huntress 23 дня назад

    The dictators sunglasses are reflective

  • Sabreen Elzein
    Sabreen Elzein 24 дня назад

    I thought about saying at least 99 of you have green eyes to make it easier😂

  • Jessica
    Jessica 24 дня назад

    I have green eyes

  • Donald Mcfist
    Donald Mcfist 25 дней назад

    I would have just poured water on the floor to see my reflection

  • Silver The Gamer
    Silver The Gamer 26 дней назад

    i still don't know how they know to get out

  • Krap In My Eye
    Krap In My Eye 27 дней назад

    Just look in a full sink or toilet

  • MarioManRoy
    MarioManRoy 27 дней назад

    did anyone else mistake the prisoners noses for their mouths?

  • Baud drum Puppies
    Baud drum Puppies 27 дней назад

    No matter what it would only take two days for everyone to leave being that they have been there since birth so they would get the time to know the other 99. The day after you leave if they see the other 99 still there they will realize that the others have been thinking that they were the only one without green eyes and that night they leave

  • Brandon Love
    Brandon Love 28 дней назад

    Why not just say it you see someone with green eyes tell tap them to go over there your not giving them new info and that's only 1 statement.

  • Robotik
    Robotik 29 дней назад

    If i saw both my parents with green eyes i would assume that i have green eyes too. its basic science. 😁

  • Arnav Agarwal
    Arnav Agarwal 29 дней назад

    Or they can just see their reflection in the sea water.

  • huddrez99
    huddrez99 Месяц назад

    I hate it when people aren't able to see this as a riddle and not real life. Just solve the riddle or don't and stop over complicating and stuff

  • Helayna Henderson
    Helayna Henderson Месяц назад

    If they can understand your statement then they can just tell the person they're looking at that they have green eyes.

  • Jaclyn Bernstein
    Jaclyn Bernstein Месяц назад

    Cool. This was really well explained.

  • Propop pop
    Propop pop Месяц назад

    Simple put the water in your palm or just know every one has green eyes so how can you be spical

    • Propop pop
      Propop pop Месяц назад

      Sorry just every one likes to find a meta solution to this problem

    • Propop pop
      Propop pop Месяц назад

      And they would all ready know 99 of them had green eyes and then some body could make a scafrifise for the greater good and shout you all have green eyes

  • Vivek Agarwal
    Vivek Agarwal Месяц назад


  • Vivek Agarwal
    Vivek Agarwal Месяц назад

    ANSWER, Stop imagining.🐶

  • Phan Trash #839
    Phan Trash #839 Месяц назад +1

    I would have said JUST LEAVE

  • E Skerlec
    E Skerlec Месяц назад

    The problem is quite easy, the first statement would work perfectly and all could leave on the second night. If everyone saw that the other 99 had green eyes, you could assume you also have green eyes because your statement ensures there must always be 1 person with green eyes at all times.

  • AxleAddict
    AxleAddict Месяц назад +1

    Want an easier solution. If at least one had green eyes, means all of them got green eyes.

    None of them had any different eye color meaning all of them had green eyes.

  • Sasha Knight
    Sasha Knight Месяц назад

    If I saw everyone else with green eyes I would have thought I had green eyes! 😝

  • TheFabPanda 555
    TheFabPanda 555 Месяц назад

    Wait, didn't it only say they couldn't SPEAK to each other? Why wouldn't they use some other form of communication? Like just pointing to their eyes, then them, then the exit? "Oh, they're telling me to leave! Gotta have green eyes!"

  • Pea Nut
    Pea Nut Месяц назад

    Wait wait wait why would adria and bill think that the other one would be the only one with green eyes when they everyone in d morning attendance.
    Sorry if i m being dumb but i just dont get how it works.

  • Rufino Bartolabac
    Rufino Bartolabac Месяц назад +1

    solution: throw the dictator into the volcano, making gravestone shaped smoke.

  • Madeleine Poirier
    Madeleine Poirier Месяц назад

    can't I say "at least 99 of you have green eyes" ? I mean, it's not a new information cuz they've seen each other's eyes

  • gabriel burfitt
    gabriel burfitt Месяц назад

    Why don't you just say you can all leave?

  • The engi main Dispenser
    The engi main Dispenser Месяц назад +1

    They where in there since birth? So if you're innocent and you havent done anything you are arrested

  • Nonsense XD
    Nonsense XD Месяц назад

    Wait am i stupid but why didnt they just look into each other eyes and just nod if the other person has and if they dont just dont nod. I dont know if that allowed but im just asking.

    • NoNameC68
      NoNameC68 Месяц назад

      Keep in mind that the puzzle isn't about abstract thinking, it's about coming up with a deductive solution. One must assume the only way to escape is to look into the other person's eyes and use deductive reasoning.

      I honestly HATE the way this puzzle was worded, because it does a bad job of both explaining the solution and it doesn't go over what would happen if some of the other people had brown eyes - not in enough detail.

      It's a difficult puzzle to frame in a scenario. Over a year ago I came up with what I felt was a better scenario - but it was also more wordy. The difference is, my version was much easier to understand.

  • Gert Jan Van der Gugten
    Gert Jan Van der Gugten Месяц назад

    they can only keep track of 1 person per day?

  • Gert Jan Van der Gugten
    Gert Jan Van der Gugten Месяц назад

    dude im so confused... as ALL the prisoners already knew atleast 1 of them has green eyes.. why couldnt they leave earlier? or DID she tell them new info but the dictator just didnt notice?

  • Joe Piazza
    Joe Piazza Месяц назад

    Can someone explain please. This makes no sense. Okay so with 3 people to make it easier. If all have green how could anyone deduce they are green themselves? Lets assume person 1 has Brown Eyes and the others have green. Person 1 can't leave right away because there are 2 green eyes. Person 2 and 3 see 1 Brown and 1 Green. They can't leave either as the condition is fulfilled. At least 1 has Green eyes. For all person 1 knows, they see the others are Green and are uncertain about themselves. The same amount of days as people makes no sense too. Adding 1 person per day won't change anything if you do the same experiment with 1 Brown eyed person. No one will leave. Not unless they saw everyone else had non-green eyes.

    • Joe Piazza
      Joe Piazza Месяц назад

      I totally get it with 3 now. I shouldn't have done it so late. I'm still trying to get my head around 4+. How does adding someone solve this? And how do the number of days matter? How could anyone potentially leave if the group not involve in the smaller earlier days groups still matter?

    • jiold
      jiold Месяц назад

      Joe Piazza At first I thought you were right, and thinking through the problem makes my brain hurt a bit, but it's essentially thinking through what others are thinking (this is a lengthy explanation). Ok, so let's say I'm person 1 (with three in the group). I conclude that I have brown or green eyes. So I can consider both situations.

      If I have brown eyes: person 2 sees one person with green eyes. They can deduce that person three sees either no people with green eyes, in which case person three would leave on the first night, or person three sees green eyes and does not leave. Again, if I have brown eyes, then on the second night, person two can then safely leave on the second night, since person two knows person three sees him as green eyed.

      However, when person two does not leave on the second night, I can conclude that I have green eyes and leave on the third night (because if I had brown eyes, I know he would have left the second night).

      The key for me is placing myself in the situation, then it becomes considering what other people are thinking. From three, you can extrapolate to 4 people. In that case if I have brown eyes, they will all leave the third night, as person two sees two people with green eyes, and goes through the same reasoning (since there are three people with green eyes). If they don't leave the third night, I can conclude I have green eyes and leave the fourth night.

      I hope that clarifies a bit. It ends up this weird situation, where person thinks that person 2 thinks that person three thinks that ... etc.

      It seems unintuitive, but it boils down to a recursive problem. If you can solve for n, you can solve for n + 1. They should really start with one person with green eyes. If there's one person, they would leave because they know they have green eyes (as everyone else he sees has brown eyes). If no one leaves they can conclude there's at least two, then three, etcetera.

  • Logan Jackson
    Logan Jackson Месяц назад

    Wouldn't they have to know that all of the other prisoners are also perfect logicians? Otherwise, they could assume that someone likely screwed up the logic.

    • Logan Jackson
      Logan Jackson Месяц назад

      Either that, or it assumes that you will be able to see everyone's eyes at some point in the 100 days. My guess is that they all know that all 100 are perfect logicians but idk how they'd know that if they can't talk to each other.

  • Loopa Apool
    Loopa Apool Месяц назад

    They just spill the water and check lol done

  • Ethan 15
    Ethan 15 Месяц назад +1

    I Would Have Just Said "EVERYONE ATTACK THE GUARDS!!!" And Start A Riot

  • aidan lee
    aidan lee Месяц назад

    Just stop imagining!

  • Ryan Johnson
    Ryan Johnson Месяц назад

    Pour the water that they provide out onto the ground and look in it

  • random person
    random person Месяц назад

    I thought to say: everyone around you has green eyes.

  • Rebecca Hammond
    Rebecca Hammond Месяц назад

    Well at least I know that if I get trapped on an island by a dictator that I can escape

  • Rama Pasupula
    Rama Pasupula Месяц назад

    0:39 The guy has RED eyes

  • Spence Co
    Spence Co Месяц назад

    just say "everybody around you has green eyes" and sense that i'm saying this to all of them they can work out that means they all have green eyes, so I've told them what they already know, so they can work out something new!

  • King kid Gamer
    King kid Gamer Месяц назад

    Wait of course they all have green eyes if they didn'why would they be on that inland it makes no sense

  • God `n me Puzzles
    God `n me Puzzles Месяц назад

    Help us to grow up, downloading and playing these funny game
    Ayudanos a crecer descargando y jugando este divertido juego

  • super555555555555
    super555555555555 Месяц назад

    Why didn't the guards just lie? They never knew they have green lies so they can still be killed

  • forest wow
    forest wow Месяц назад +1

    pour water on the floor and watch yourself.. :D

  • Enrique Flores Blanco
    Enrique Flores Blanco Месяц назад +1

    The people are quite lucky: they have been born there, everyone has green eyes and are perfect logicians. What are the odds?

    another question
    Why the heck my phone changes logicians to opticians and opticians to logicians

  • humixmusic4lyf
    humixmusic4lyf Месяц назад +1

    this makes no fucking sense! They don't know what the colour green looks like.
    The two people example, person #1 wouldn't think that they've got green eyes if person #2 hasn't left because they both know, that they both don't know what the colour green is. So either way person #1 + #2 wouldn't risk asking because they'd both still think that there's a chance 'I could be the non-green eyed person'.

  • Mohaimenul Haque Adnan
    Mohaimenul Haque Adnan Месяц назад

    Why not just tell them, "Each of the inmates you see has green eyes."

  • Lincoln Paogofie
    Lincoln Paogofie Месяц назад

    Couldn't you just say that every prisoner you can see on this island has green eyes. That means that if you are on this island and have been seen by anyone then you are green eyed.

  • Twist t
    Twist t Месяц назад

    how about get the helicopter go to the tower say tha everyone has green eyes and leave

  • ben ellam
    ben ellam Месяц назад

    y not just say "everyone around u has green eyes" they already know that but for that to be true for everyone that means everyone has green eyes

  • Sean Wilson
    Sean Wilson Месяц назад

    could you have said that all of them could leave?

  • Mario Gomez
    Mario Gomez Месяц назад +2

    This video has subtitles in almost every language except german! 😡😭

  • Ash N
    Ash N Месяц назад

    This riddle is kind of stupid. Ok, at least 1 out of 100 people have green eyes, meaning anywhere from 0-99 people DON'T have green eyes. Just because you have green eyes and stay, doesn't mean it's because I have green eyes (since you can presumably only tell by who stays, and the timing when they go, + knowing greens eyes are possible, though not being told that they are probable for you). We could basically all just go on seeing the persons green eyes next to us, but thinking they see that our eyes are brown, and THINKING THAT THEY THINK theirs are too (since, again, the specifics are unknown, 0-99 possible people with brown eyes still means you both COULD have brown eyes, even though you know the other person doesn't). I just don't see how this is the best way to be 100% sure.

  • Isaac Lee
    Isaac Lee Месяц назад

    what about this one:

    "all of you know that, besides yourself, every one in the prison definitely has green eyes."

    this shows that every one else sees only green eyed people, therefore you must also have green eyes!

  • Davi Direct
    Davi Direct Месяц назад

    The problem with these riddles are that no one thinks like that

  • ItsFernal
    ItsFernal Месяц назад +2

    what if i pour the water in my hand, and saw my reflection?

  • Exactly Pi
    Exactly Pi Месяц назад

    99 or more of you have green eye

  • Vox Vino
    Vox Vino Месяц назад

    How Bout, Everyone Has The Same Eyes?

  • Rozemira
    Rozemira Месяц назад

    Say "At least 99 of you have green eyes." And they can all leave on the 2nd day.

  • neplinDream
    neplinDream Месяц назад

    you could also say 'At least two of you have green eyes.'