This problem is adapted from an Oxford University admissions question. They say if you can solve this in your head, you are a genius ;)
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It’s also necessary to let the viewer know that Shilpa knows that Colin knows the color and that Colin knows that Shilpa knows the shape.
This comment needs more likes.
That is the "the setup of the game is common knowledge" part.
That is part of the setup, which is stated to be common knowledge
literally one of the first things mentioned
Yes yes yes yes
Alternate universe: Shilpa and Colin are NOT perfect logicians. The Host continues to ask "Do you know now?", continuing to get the same response of deafening silence for infinity.
😂😂
We call that universe “reality”
I managed to figure it out in my head in under a minute but if somebody was asking "do you know now?" I would literally not even be able to figure out the first elimination.
@@austinbentley4604 you would have to know the person you are with and know they think logically.
@@williammeek4078 hahaha imagine if only one of them was, third time : Yes! *Looks at the other who doesn't know*... Well nevermind...
There is an unstated assumption here. They both have to know what kind of advice the other one got. Shilpa cannot make the decision described in the video if she does not know that Colin has been told the color. He might, for example, have been told which row the prize is in.
But this riddle was not given to Shilpa and Collin to solve. The situation described is a riddle itself, so we have received the information that Shilpa and Colin were told shape and color.
@@klaudia2141 you missed her point. Yes, the riddle is given to us. But for us to make the logical decision based on shilpa and collin answers, they need to both know which info they both got before the riddle even started. Example, if collin don't know that shilpa knows the shape of the answer, he will forever be silent (unless it's yellow) and vice versa.
@TheWeeaboo Please explain how any of you would know it's the green triangle if shilpa doesn't know that collin knows the right colour and vice versa.
@TheWeeaboo "if it was anything else than the green triangle, either constestant would have know this" how? For the green triangle we're just assuming they know each other's answer and that's the whole point of the original comment. If it's for example the blue triangle, collin knows it's the color blue, but doesnt know any other information. So no matter how many time you ask, he will forever stay silent. The same thing goes for shilpa. So you need to assume that they know each others info
0:26 It is specified that the initial setup is common knowledge.
I'm glad that I had time to study this over and over. I am surprised at how satisfying it feels, but I also realize that I could not have figured it out on my own (i.e. without the video's help). That sort of frustrates me, but it is what it is.
Three logicians walked into a bar. The bartender asked, "Do y'all want beer?". None of them replied. When the bartender repeated the question, they said in unison, "Yes".
A beautiful simplification of the same riddle. Common knowledge and deduction.
I've heard this one before but phrased in the context of a joke
@@NevaehBeatezlooks like a joke to me
I tell the version where they’re asked “do any of you want beer?” and the first one says “I don’t know”, the second one says “I don’t know”, and then the third one says “no”. Sort of the reverse joke.
genius!!
When you realize that the lack of knowledge is actually a piece of knowledge in itself.
This little tidbit here is not to be underestimated; as soon as I saw your comment before I had solved it, I knew I was looking at it wrong and was then able to figure it out pretty easily. Nice looking out.
Ridiculously underrated comment 👏🏻
Yess
Yes, elimination methods are always fun
That’s how military intelligence works, sweetheart.
This is something that one has to really concentrate and think about the two people and what they were told and their responses! It's great.
I was so thrown by the silence - as if that’s a reasonable response to a professor’s question. At least they could say “not yet” if “no” is not appropriate for some reason.
Having taken a Cambridge admissions test this week, I can confidently say they’d never be this easy.
Ok good, also good luck
@@johnmarston3983 too late for that. F
@@seastilton7912 F 😐
WHAT
What was the interview like
Finally a problem i could solve on my own before watching Presh' answer. I'm so proud of myself rn
this one is kinda easy tho.
good job!
@@midfidelity7180 :(
@@midfidelity7180 c'mon atleast they tried ...
Well pack up you’re going to Oxford!
Great video! I love solving logic puzzles and this video definitely challenged me. The variety of puzzles kept it interesting and I appreciated the clear explanations of the solutions. Can't wait to try these out with my friends!
2023 Computer Science A level students know what's up (it was a question in the exam)
didn't seem like a hard question at all. depending on how much time you got. if you have all the time you need, a child can solve it. if you got 5 minutes most adults should be able to solve it.
Reminds me of a joke: Three logicians walk into a bar. The barman says "would you all like a drink?", The first logician says "I don't know", the second says "I don't know", and the third says "yes".
please explain 😭
@@syupdengixx The first logician wants a drink, because if they didn't they would already know that not all of them wanted a drink. However, they can't be sure that the logicians after them also want a drink. The second logician wants a drink, because if they didn't they would already know that not all of them wanted a drink. However, they can't be sure that the logician next in line also wants a drink. The third logician knows that neither of the two before them has declined a drink, and knows that they themselves also wants a drink, so therefore all three must want a drink.
As someone who is currently studying for the LSAT, this joke both makes me laugh and bothers me 😂
@@thecookieeater oh ok!! thank you so much for taking your time to explain it
I don’t know!
Me, a 21 year old who’s going to graduate *NOT* from Oxford University: Yes, I’ll definitely keep this in mind for my interview.
Good Luck !
How did it went?
Army
Literally me 😅 though i graduated July
@@stellarworld8477 Sarcasm
I got it too, but the "silence" response, as opposed to a simple "no" answer confuses it unnecessarily, and took me longer.
If taken literally, the silence option is an indeterminate factor, since without the mediator intervening repeatedly there would be no certain moment at which either would know for certain the other had not gotten it; that is to say, the moment they realise the other has not gotten it and knows they also have not gotten it, both should already know what the answer is, given they each have perfect reasoning and are apparently aware that the other also has perfect reasoning. That said, I think it's obvious what the silence signifies.
We could think that they were whispering to each other
Since no information was given in the answers or questions, it was obvious there was none in there. So you could discard that right from the bat. Its totally irrelevant
I actually got stumped on a simple assumption; silence could mean anything.
Oxford's real life admissions question: "Would daddy be paying cash or credit card?"
💀
Truth
Amen!
That is clearly the more important question. Ha, ha.
All that matterzzz baybay!!
i love how everyone says 'this is so easy!!' and here i am just like 👁👄👁?
same, I don’t understand the explanation lmao
People lie
@@Dark_Tesla I belirve alot of people just know rational thinking more than others, it's one of those chanels and it would attract similiar minds.
@@bonecag3 assuming these people know that the girl focuses on the shape, and the girl knows the guy focuses on the color. Then they just sort them and know what color and shape to elimimate from both color and shape.
@@222MovieMan people love to stroke their egos too. This is the internet, I’ve seen what people do for a like.
Love these puzzles! Keep posting them Presh!
Absolutely fantastic! Paused the video, paused it, solved it and moved to the end and was like Taaadaaaa!!! Had done a similiar one involving hats and folks sitting back to back to each other! 😬
Neat, wasn't sure how the silence played a part but once I heard that it was a part of eliminating possibilities I got it
Same
the silent is used to decide what it cannot be.
Same, the more you know i guess
Always pay attention to detail.
Not mentioning the elimination steps is a fault of the test. IMO. Remaining silent to me means they were just refusing to reveal what they knew.
I guessed red hexagon.
Same.
These shows always have their trick
Same
You will be contacted. Our agent will ask for directions on the street and show you a map with a red hexagon. You will reply "Three blocks west, and I recommend the fish chowder." Bring nothing, the training facility will supply all your needs.
Does “...the initial setup is common knowledge” mean that both Shilpa and Colin know that the other was told the value of the opposite characteristic of shape or color from what they themself were told? Or does the setup refer to the shapes and colors of the objects only? This is not explicitly mentioned and is crucial to the ability to solve the problem by Shilpa and Colin, and therefore to our ability to be sure whether the responses by them are given with certainty or not. If the meaning of the quoted phrase does not mean this, the problem as presented is incomplete because it requires us to assume each person knew what characteristic-though not the value-the other was told or even whether their counterpart was told anything. All we know that they know is that they knew what they themself were told privately. There is no mention of anything with which either-much less both-of them could have deduced what, if any, information the other was told, so this would require each of them to make an assumption about what the other did or did not know. Therefore the problem would be unsolvable with certainty by either of them and the information we are given regarding their responses cannot be assumed to be correct and without uncertainty, therefore the problem is unsolvable with certainty by us. So we can make an assumption and solve for the green triangle, or go with only the known information and conclude there is not enough information given to arrive at a solution with certainty. This is the complete solution to this problem as stated. Sloppy statements in a setup for a problem of logic lead to problematic solutions.
The real test is actually solving it with another person and a host asking you the questions. Recognizing the logical solution is the beginning, conveying that to someone else is what matters. Source: definitely didn't get into Oxford, but I'm still trying really hard.
I went through the entire process in my head in about 10 seconds, while having tea and a Choco Pie, without even realising the logic of what I was doing. It was just: "OK, it clearly can't be these two". I only had to think about it at the last step, when the two triangles and a circle were left. And even then I only did it after arriving at the obviously correct answer during the initial 10 seconds, just to double-check myself and ask: "But why?". Funny thing is, even after double-checking myself I still couldn't lay out the entire logical chain. That's heuristical thinking/Kahneman's System 1 for you.
So the moral of the story is: - always ask mathematicians your question at least 3 times
Can you tell me some other channels where I can find these types of mathematical riddles 🥺
@@ThatAsianGuyExplains kzhead.info/tools/6jM0RFkr4eSkzT5Gx0HOAw.html
"Who does #2 work for???" -- Austin Powers.
@@ThatAsianGuyExplains kzhead.info
Maybe this is the logic that Asian parents use to teach their kids math? 😂😂
Figuring this out beforehand feels so validating, i realise that i finally grew some braincells🥺
hahah same
Fr i dunno how but i figured it out before the explanation
wait someone actually understood this fkin thing?
It feels good at first but I'm conflicted. On one hand, this is presented as a difficult problem. On the other hand, I found it very easy, and I don't know if that means I'm really smart, or I've fallen for the kind of trick used by fake online IQ tests where they ask an easy question and praise you for it.
@@gilliann.9579 you did not have to go that hard on an online test for funsies😭😭😭😭
I love me some AqA computer science
Interesting puzzle! I only recently studied the rational speech act which is about pragmatic communication, and I noticed almost instantly that the same reasoning applies here.
I'm an accountant, so this was easy for me. MY 'EASY' ANSWER WAS: _"I don't have a freakin CLUE which object the prize is under... but _*_let's talk about the tax implications on the value of whatever the prize is, and I can tell you about the special pricing we're having for our tax prep services."_*
You spend way too much time in the office lol.
Lol
Haha ROFL!!
666 likes
I didn't know a green triangle was taxable.
Yes! I managed to reason through it all on my own. That’s quite a satisfying feeling.
i solved it also and im certainly not overly smart. I did however assume (coz we were not told) that each knew the other had been given a different clue
Same here …solved on my own …yayy
@@ExplodingPiggy you good bro?
Me too....that feels good
@@ExplodingPiggy ironic
Colin knew it was under the yellow circle from the beginning, but remained silent trying to confuse Shilpa. Such a smart*ss Colin is!
1st choice: square and yellow are out. 2nd choice: circle and blue are out. 3rd choice: only one shape is left - the green triangle.
I know it's not hard at all but I felt so happy getting it so quick
Us bro us
Sem
Me too!
Me 2
@@user-tt7wu2zh7h πάμε ρε Γιώργο
I went into this riddle thinking that Shilpa and Collin didnt know what the other knew. I had too rewatch this vid to read “The initial setup is common knowledge” I missed what that meant at first 🤦♀️
Or that "initial setup" includes the questions each was asked, which is more doubtful when they are 'asked quietly'. Janky - trying to hide the premise.
The initial setup is the 5 colored shapes you see on screen and the fact that one knows color while the other knows shape. Each "silence" is a "no", eliminating two places it could be under for both people. Like, say it were yellow, then one who knows what color would've immediately said yes the first time, and the only single color on the board was yellow. Since they both stayed silent, it was eliminated as a possibility. Same goes for the square being a one of a kind shape.
But since the circle shape object can easily fit under the square this is not a logical puzzle..
@@mariolanz4187 ...what does that have to do with anything? The puzzle'w answer is contingent on shape, color, and the same question being asked thrice, not what shape can be hidden under another. The shapes and colors are just the setup, the logic portion is in the question.
same, i thought the initial setup meant the order he set them uo
One of the few I managed to figure out. I'll take it as a consolation price. Cool video, thanks!
After watching a couple of your videos, this was a really easy puzzle! I literally solved it in a few seconds lol
I get the logic.. But the yellow circle was still my favorite, and I feel it should have gotten the prize
Exactly.
yellow curcle was robbed ;(
Green triangle made me feel offended therefore i insist that it is the wrong answer
We'll give you a participation trophy.
Yellow circle was the red herring.
It was much easier for me to mentally cross out which choices were impossible, rather than make a list of all possible choices.
Same! Very logical and easy.
figuring out is always easier and less time consuming than explaining the process to a mass of people.
@@mohamadrezahesan881 sure, but they explained a slightly different process
You wouldn't know the "impossible" choices without the whole information ;) something to tink on
@@MyNameJeff00 that’s not true at all. I paused the video and literally went “okay square is impossible, yellow is impossible” etc. until I got the answer
What a cool puzzle! Really gives your brain something to chew on and makes you focus almost 100% in order to deduce the right answer
It's actually a neat puzzle with no hooks. Took me a minute.
getting this in my head is one of the proudest achievements in my life
Same lol
I came to the correct answer but not the same way, after the first silence I knew it couldn't be the square or yellow but I didn't remove them, then I ask what other colors would give more options my figuring blue triangle and the green circle, being that triangle & blue were already represented and circle & green were already represented then actually removed them from contemplation. This left me with three unique shapes w unique colors two which I were TOO unique to be correct as color(yellow) and shape(square), leaving me with the only option of Green Triangle. Hope this was interesting and not a total waste of your time 🙂.
@@indebtfolife same
It's not hard
Yea, is this really an oxford admission puzzle? It seemed surprisingly easy. :/
That was really interesting. I've never been able to understand that sort of logic puzzle as my mind just goes blank. It was great hearing the explanation as it actually made sense and gives me hope that one day I'll actually be able to work one out.
I like to think of these kinds of puzzles as exercising a different brain ‘muscle’ than we’re used to using. If you think of it like that, it’s easy to understand that ‘mind going blank’ response. If you put me in front of a set of dumbbells, I would stand there like “uhhhhhh….” and probably just leave. I completely get it. I totally believe in you!!!! 💜 Work those logic muscles and show yourself how awesome you are!!
@@TBadalov Seriously did you just say that because l don't understand logic puzzles l lack empathy? Go find a mirror bro.
@@sally8708 Thanks Sally. I shall replay your words of encouragement in my head from now on whenever l see a similar puzzle. It's not very objective, l know, but I normally consider myself quite intelligent. Lol. These sorts of puzzles have defeated and frustrated me all my life. I think that's why l enjoyed the explanation so much 'cos for the first time ever l could see some sort of logical process.
@A.J. Ello, yep but the defense mechanism will not allow to accept the truth and think reasonably. Some problems in life are solved naturally when got the right attitude
@@TBadalov ...how about they are just bad at puzzles???? I'm the same way, and i'm the same with sudoku, or math, or science problems where the process for how to do something that was never explained to me.
Use the principle of uniqueness/certainty : First, 1 Yellow, 1 square. The silence (=uncertain, = non-unique) ruled out the yellow and the square. Next, 1 circle, 1 blue. The silence (= uncertain, = non-unique) ruled out the circle and the blue. So, only the green triangle left.
Nice job of organizing your solution, Presh.
This was a simple one, but really fun! It almost sounds like those ones in the Professor Layton series
I heavily recommend anyone who enjoys these videos to get those games - they're quality
Can someone tell me some other channels where I can find these types of mathematical riddles 🥺
I LOVE THOSE GAMES.
Whoa, I solved it while the question was narrated. Really like this type of puzzles
@@ThatAsianGuyExplains Look up TED-Ed Riddles :)
Not gonna lie, when it was said that “the initial setup is common knowledge,” that kinda just flew over my head. Had I known that this actually meant that Shilpa was told that Colin knew the color, and Colin was told that Shilpa knew the shape, I probably would’ve been able to deduce the answer better. It wasn’t until I watched through the second step of the solution that I realized they both knew that they had a different piece of information. This would’ve made solving it so much easier.
I also misunderstood that phrase. I thought it was meant to clarify that common knowledge dictates the names of the shapes and colors in the puzzle. I just assumed, they have to know about each other's knowledge for the puzzle to make sense :D
Haha I thought he meant that Shilpa only knew the shapes and Colin only knew the colors.
Same XD
I thought he meant the initial set-up of the question is common knowledge.
@@BenBike Same. In my head. How can they know where the prize is if the other only knows the color but not the shape while the other person know the shape but not the color. There are 2 pairs if identical colors and 1 unique color. Same with the shape, 2 identical pairs of shapes and 1 unique shape.
Was able to solve this really fast but only thanks to your explanation of the tree prison puzzle that has a similar setup
I'd suggest that instead of the players being "silent" when asked the first two times if they know where the prize is, you have them both answer "no". Being silent didn't really mean anything.
If they answeared "no" to "Do either of you know where the prize is?", they wouldn't imply they knew the other's ignorance? But they didn't, since they waited until the last question to give the solution, based on the information of this same ignorance, which was discovered only gradually. True, the "Do you know now?" is ambiguous, and could have received a negative answear, if they interpreted the "you" as singular instead of as plural, or if they thought that, even if plural, both of them sould have to know to answear "yes"; but they were probably guided by the first and inequivocal question, therefore they sustained the former understanding.
None of what is said is relevant, from the very first question "do either of you know.." You have all you need to know before that starts. 1 knows color, 1 knows shape. And both know that each has gotten that information. There is only 1 yellow and there is only 1 square. Both need to be discarded and both people would know that they should be discarded, bc none of them can have been given the correct answer. That would destroy the logic puzzle, which would be illogical. So thats not valid. Then they would both be left with green triangle, blue triangle and green circle. Same thing again. It cant be blue, bc there is only 1 blue. It cant be circle, bc there is only one circle. So its green triangle. Which they both would know.
I love solving these kinds of logic puzzles. And am a little bit proud of myself for pausing, thinking it through, and getting it right.
Try thinking with portals:)
Same. Once you get it you realize it's quite simple and it follows the same mechanic three times. It was fun to imagine Shilpa and Colin intensely staring at each other while making deductions lol
Fr i feel so smart as someone who’s actually still in middle school but still could solve a freakin “oxford puzzle” like bish what does this meann
@@youssefrahou7990 I know exactly what you mean xD
@@youssefrahou7990 means you are listening in school keep up the good work and become somebody someday or do whatever you want
oxford interviewers: **ask this question** me: **walks out of the room** frick I'm going to community college
I went to community college and having gotten the answer right I now want to apply to transfer to Oxford.
+Looks at interviewer+: _"Dude, I'm going to law school, we deal with firm tangible evidence that we must explain to people who in some instances can't read or write."_ 🙄
Didn't need to pause the video, but I got into an even better place! Glad to see my thinking skills are intact.
I got that one right away. I noticed there was only one pattern that could be repeated properly. At first I thought it would stand out, but then I realized that too many stood out, and I went with the only one that perfectly blended in
illuminati:guess i am not so sneaky after all
me: "Damn I found the right answer" me: "Mom I'm going to Oxford!" also me: *keeps pulling a door which says push 😆
😁😁😁
?
@@sorenstamify What's confusing you?
I, too, attended Midvale School for the Gifted.
You: should delete the first two sentences to make your comment true.
This would have made more sense to me, if instead of remaining silent after the first two rounds they said "not yet". Because I didn't interpret the silence as a no.
Silence is complicity... to admitting that Oxford is bollocks.
I assumed the silence was just a third state in a three state situation Yes/No/I don't know.
@@thelazy0ne but in the situation “no” and “I don’t know” are the same right?
@@sean-mo9gf No, they are not, assuming you would give one answer and lock that in. Imagine one of them WOULD'VE known first round (i. e. Colin was told "yellow" or Shilpa was told "square"). Shilpa cannot answer "no" until she knows Colin's answer. Because if Colin's answer is "Yes", then she can deduce that color alone can identify the object, so she knows it's the yellow circle as well. So her definitive answer depends on Colin's answer - if it is "yes", then her answer is "yes" as well. If his answer is "no", then her answer is "no" as well. Colin has the same problem - he doesn't know either what answer to lock in for this round, until he knows if Shilpa says Yes or No. So both their answers are dependent on the other person to answer first. This is a deadlock, and both cannot answer first. This of course only makes sense if you can only say "yes" or "no", and your first answer is also immediately considered your final answer for this round and has to be correct to win the prize.
i thought they were silent because they didn't want to reveal the answer to the other person
For those who are stumped ur going off based on assumptions of how the two answers should overlap. U can cross out answers based on the information the two ppl are given, e.g the lone blue square and yellow circle stick out and you’re going to continue to weed out the choices until you get to a point where the choices can match up for both ppl asked the question.
It was common knowledge between both of them so it wasn't really an assumption
I solved this in my head in about one minute. But then I've written several books of logic puzzles so they're my speciality!
You should really clarify that they both are told what information the other has. Otherwise, to solve this you need to make the assumption that Shilpa has been informed that Colin knows the shape, and that Colin has been informed that Shilpa knows the colour (you state that they have been privately told, which could easily mean that they haven't been told what the other knows)
It says at the beginning that the initial setup is common knowledge.
@@Headless_Hessian Yes, I agree with your comment and the first comment in this thread. 'Common knowledge' was super vague to me in this context.
@@Headless_Hessian initial setup is the whole setup in this instance, there is no additional setup beyond the initial setup... in fact it was redundant to refer to the setup as the initial setup. "And the setup is common knowledge." is how they should've said it.
It was pretty said pretty clearly, but ig the term initial setup did leave room for confusion.
@@5eater551 That's also ambiguous: intitial setup could mean the colors and shapes available
This is how I always win at Clue. I make a huge grid and every single guess someone else makes I record and work backwards!!
The trick to wining at clue is to ask yes or no questions with OR conditions -- does the person have glasses OR is bald? If no, you can eliminate more. If yes, you can eliminate more.
@@buffordbutters6284 that's not clue that's guess who. . .
Ive tried this but I always get beat out by someone willing to make wild guesses rather than waiting till they've actually solved the logic puzzle
@@averywallace6677 Oh yeah, brain fart! 🤣
I ask cluedo questions with cards I have just to mess with others trying to glean information from my questions.
me: scrolling on youtube to find something to watch while I eat youtube out of nowhere: "solve this to get into Oxford" me: ...fine, you won again youtube
I found it super easy barely an inconvenience. It’s straightforward logic. I find it har to think that it was an Oxford University entry question.
This one is fairly intuitive. When they're both silent after the first question. we know it's not yellow or a square. and when they're both silent after the second question, we know that another iteration is required. and since the green triangle is 2 iterations from both the yellow object and the square object then that must be the answer
Yes
@@odar9729 yeh pretty straight forward...
ikr can i go to oxford now or what
Yep! That’s exactly what I thought as well.
Yeah.. the video JUST TOLD YOU that. Why are you just repeating the logic?
Happy to say I did figure it out, and it does definitely take a certain kind of thinking. The kind that actually feels good and like a small revelation when you finally know for sure. Nice puzzle!
Couldn’t relate more. Definitely feels like a superpower and super fun to train your brain!
Dude I did it too! Rather rapidly I might add. But I've done similar withheld info logic puzzles before
Did it relatively easily, 5 minutes. Just had to think of "what do they figure out from each other every time?". Pretty darn cool puzzle.
I thought it was extremely easy, wasn't it?
@4Runner telling someone what they thought is a lie doesn't make logical sense. It was easy for him, he is asking others if it was easy. That is a subjective statement, there is no possibility for it to be a lie for that singular person because it is based on his/her point of view.
Well, that was fascinating. I struggled because I was not aware that there were removals of options implied by the host questions and that proves that I am not as clever as I thought I was ... or is it just that I an an engineer rather than from a more theoretical discipline? :D
Ive seen variations of this, basically reasoning about what the other person knows and knowing that they, being a perfect logician, can infer what you know as well.
Can't wait to get my Oxford admission in the mail because I did this easy puzzle. I knew that my Mom doing my homework throughout high-school would make me very smart!
i am dead 💀
Lol 😂
Haha same
Geniuses don't believe in hard work 😎
It wasn't as hard as I thought it would be
This is such a simple problem as long as you understand what it’s asking of you. I misunderstood the setup, thinking that Colin only knew the colors and shilpa only knew the shapes, but they in fact both knew the colors and shapes of all five, but each was told info on what the prize was.
Yeah same thing was for me also.
I made the same translation mistake 😂
I think you guys misunderstand the problem. The problem isn't simple at all. Colin did only know the correct color and Shilpa only knew the correct shape. It doesn't make sense to say that Colin knew the colors of all objects. I can also tell you that it's extremely hard to do this in your head for anyone because of how our brain works. Our brain can only handle 3-4 short-term facts at once. And, given that there are so many different pieces of information here, it's really hard to figure this problem out instantaneously. You'll need at least several minutes to think it over and over again until the short-term details become strengthened into long-term memory.
@pearlwhite21 The object is indeed under one of the weird containers. (Or, you can think of it like this.)
@@morninglift1253 no, they both know the shape and color of all of the objects, one just knows the color of the prize while the other knows the shape. It’s impossible to solve otherwise, since neither person would be able to rule anything out
At 0:18 and 0:22, we are told that each of them is *privately* told the shape or color of the object. So how am I to assume that either of them knows what the other one was told? The information given out in the beginning was intentionally misleading, since it is impossible for Shilpa to know that Colin was told about the color, or for Colin to know that Shilpa was told about the shape.
He says on 00:30 that the initial setup is common knowledge, so thry know the information given to the other, otherwise the solution would be impossible.
cant be yellow cause then colin would have said so straight away (as its the only yellow), which means it cant be circle, so both circles are invalid, that leaves 2 blues 1 green, it can't be the square cause then the woman would have said that straight away so its between the triangles, with colin knowing the color he can choose the right answer between the two triangles. though i dont know how the other person would get it, as they are picking between two of the same shape.
@@arjunjai1852 I agree wholeheartedly.
@@arjunjai1852 it's making me laugh, but at who/with? Who put this on?
Got it without pausing and before the timer started. I feel like a genius
I learned two things about myself. According to this puzzle I do not immediately think logically and I could not do this in my head but would require pen and paper. Thanks for this. This was fun. You may have set me on a road to understand more.
There are 2 ways to solve this puzzle. One is by deduction, which is probably explained (but i didnt look at that to be honest): None of what is said is relevant, from the very first question "do either of you know.." You have all you need to know before that starts. 1 knows color, 1 knows shape. And both know that each has gotten that information. There is only 1 yellow and there is only 1 square. Both need to be discarded and both people would know that they should be discarded, bc none of them can have been given the correct answer. That would destroy the logic puzzle, which would be illogical. So thats not valid. Then they would both be left with green triangle, blue triangle and green circle. Same thing again. It cant be blue, bc there is only 1 blue. It cant be circle, bc there is only one circle. So its green triangle. Which they both would know. The other is by understanding the puzzle (ill explain) and then quickly going over it visually, excluding. This method is faster, but requires training in understanding the problem given and where the answer must be. So, it requires you to listen carefully to what information is given. at start stage they say 'common knowledge', 5 objects, with 3 variations in color and 3 variations in shape. Both get ONE exclusion criterium. What you should quickly understand from that is that the prize will be under the one that has most common traits, colorwise, and shapewise. That means you can exclude all outlyers! yellow - gone square - gone left is green circle, gren triangle and blue triangle circle - gone blue - gone Green triangle left. Above 6 lines are about 1 second or less of looking at it and discarding. bc you eliminate all outlyers without having to think about it. You can train this sort of logic and understanding very well and will get better and faster at it all the time. Its fun ;]
@@StofStuiver thanks. This is keeper information. I appreciate your time. And it was fun anyway.
@@r.j.powers381 You are welcome sir ;]
Love this kind of pure logical reasoning.
This way too easy though for a real admissions test though
Logical(?) reasoning???? totally assinine!!!
I'd give you a like, but I don't want to disturb the count.
@@jimsvideos7201 Lol. It's gone up now, though, so you can if you want. 👍
@@michaelmcgregor7374 "asinine", and this problem was broken down in much the same way a computer program would need to be written to solve it, so yes, "logical".
I don’t know how like my brain knew the second step but couldn’t form it into words and the third step but I figured it out before you gave the instructions
I finally got one of these right. I'll be expecting my Oxford acceptance letter now.
The fact that I solved it in my head proves that this puzzle does not determine if one is a genius.
Exactly ;)
Everyone here must be a genius or I’m just a retard
@@prod.steezey883 lmao
I got it wrong 😑 and I have an iq of 139
@@CrAzZyTheCodingBoss then i don't think you have an iq of 139 buddy
I'm so amazed at both Shilpa and Colin who, in total silence, managed to use a process of deduction without communicating with one another. I bow to them both.
Exactly!!!!
The process of elimination. It's not that hard. based on the reaction of the other person it becomes easier and easier to eliminate
well think of it like this, they are told that each other has another piece of information. which means they can start ruling out the likelihood that the other person would have been given a clue that was basically a direct answer. So then start by eliminating what is not a direct answer. i.e. yellow and square. this leaves green triangle as the only thing remaining with a pair for both color and shape.
But they never said they did NOT know the answer. They chose not to answer either way.
"process of deduction without communicating with one another." Oh, but they DID communicate!
After reading the comments I think it’s appropriate to leave this here. The only way they both would know, after the host asks the third time, is if they both knew the other had known the missing piece of information. All the necessary clues have been given. “Colin/Shape have been privately told” just tells us they were told the adjective of the prize. This does not mean that the other person would not know what kind of info the first person was given
The prize is under the green triangle. The first time they were each silent, Shilpa's silence eliminated the square and Colin's eliminated the yellow circle. The second time they were each silent, Shilpa's silence eliminated the green circle and Colin's eliminated the blue triangle.
I was able to get this puzzle correct on the first try; however, this puzzle makes the assumption that Shilpa was told that they told Colin color, and Colin was told that they told Shilpa shape. If one didn't know what the other was told, this puzzle would not be solvable.
The video says “Shilpa knows the shape” and “Colin knows the color”, then says “the initial setup is common knowledge.” So yes, it would not work if they didn’t know that-but the puzzle states at the outset that they did.
@@12mountain 0:16 They were both privately told, so there would be no way one would know that the other was told, and the puzzle states that.
@@celts3760 The wording is vague, but Bart is correct: it’s common knowledge that Shilpa knows the shape and Colin knows the color. The information that was communicated privately is *exactly which* shape Shilpa was told and *exactly which* color Colin was told.
@@notanetdeck5264 "Shilpa and Colin are mathematicians who use perfect logical reasoning, and the initial setup is common knowledge." For a "given" to be valid in perfect logical reasoning, it has has to be explicit and clear; not some vague implicit assumption. No where in the video do they explicitly state that Colin knows that Shilpa was told shape and Shilpa knows that Colin was told color. The initial setup could be nothing more than them knowing the shapes and colors used. That alone is not enough for people who use "perfect logical reasoning" to know that the other was told. If you can, provide a time stamp where it is explicitly stated that one knows that the other was told, but I couldn't find one!
@@notanetdeck5264 oh, i thought initial setup meant the setup of the shapes
This test becomes a lot easier when you realize the two of them are gathering information from the other's responses😅
That’s the whole point of including the fact that they were silent.
jus wait a minute, how does shilpa knows, that which one is yellow, she hadn't been told the colors? (after the 2nd question)
@@subhajit1128 Colin knows the color. Shilpa can deduce that the color is not yellow from Colin's silence during the first instance of "Do you know," because if Colin WAS told yellow he'd immediately have an answer.
@@subhajit1128 Exactly! The initial conditions are totally confusing. I got it that one only knows the shapes and the other one - only colors. But no, they know both. It's only the shape or the color of "the object" what was told privately. And this "object" is actually "the prize". I don't know, maybe it's me not being native English speaker, but from my point the conditions are formulated ridiculously unclear.
@@valentinap2432 Shilpa is told the shape, Conor is told the color, and they deduce information about what the other person was told based on their respective responses to a third party asking "Do you know where the thing is?"
wish i applied to oxford and had this question :') i'm surprised i solved this one fairly quickly
It is quite simple bc there is only ONE object that has both its colour and its shape twice in this puzzle: green and triangle. So the green triangle must be the solution.
You forgot to mention the fact that Shilpa and Colin can both hear/see each other, that is a HUGE determining factor when they base their next answer off of the others response.
and that they both know that Shilpa knows the shape and Colin the color.
Exactly. I was figuring out it couldn't be the yellow cirlcle or the square, otherwise on the first try either of them would have found the object. But I assumed they were figuring out the problem together by talking.
How else is this supposed to work? Magic? Obviously they have to be able to observe each others reactions, otherwise the "Yes" at the third stage wouldn't make any sense.
Thanks for admitting that you got it wrong
Exactly! I thought they were both told privately. Knowing that it's pretty simple.
I am so bad at these but I actually got this one. I needed that boost today.
Was your process the same as that in the video? I got it too but I my reasoning was completely different. More of a educated guess than reasoning lol
@@joshuazatarain7967 I think yes, for the most part. My thought process was sort of "Well, I don't know what it is, so is there anything that it can't be?" and "okay, then what's the significance of it being 3 times?"
after the first help (Ie realizing the meaning of the first silence) I figured it out... what a nifty puzzle that is honestly simple once you get it
I’m glad that I finally got one of these.
I LOVE how this work. It seems so impossible at a glance, but is fun and fairly simple to work through once you realize the process of elimination.
The blue □ and the yellow ◯ are unique in shape or color. So they are eliminated in the first round. Then the blue △ and the green ◯ become unique and eliminated in the 2nd round. Now, only the green △ is left.
Why though? We cant assume what silence means. Maybe one knew what it was and didnt say. And while we only knew they were silent, we dont know if they used non verbal communication either. Riddle relies on making assumptions.
@@phalcon23 It was said they use perfect logical reasoning. So they're basically like "computer code". They are silent because they both knew the other won't have the solution yet. That's part of the puzzle. And when they knew, they told so, as that's what they have to due to the perfect logical reasoning. Also, non verbal communication is communication too.
@@ggdk2865 well as someone who writes computer code, that is not perfectly logical. If you ask a yes or no question, you expect to get an answer back, never silence.
@@phalcon23 Not really. The question is "Do either of you know where the prize is". Logically, they don't know what the *other* one knows. So they can't say either yes or no. Therefore, silence.
@@ggdk2865 well they cant lie, so if one person knows it, they would say yes, and the other one could also then say yes as well. you could also add 3rd opttion "unknonwn, or not sure" logic doesn't have to be binary.
I saw a similar puzzle just yesterday. Once you know the approach, it's trivial, but understanding which approach you have to use is somewhat tricky.
I've got Brilliant to thank for me knowing how to solve this problem, it thought me a lot about what someone not knowing something can tell you
The puzzle itself was pretty simple, but the "Do you know now" control part of it was rather ambiguous. If they were both equally fast at processing the logic, that part would be redundant. If they were not, there would be no way for them to know if the other's silence is an indication of choice or simply the fact that they didn't finish the "stage" yet, which is what the explanation and the question itself assumes. Maybe if the puzzle added something like "They were both given 10 seconds before I ask for an answer... and so on" would make it more clear. I hope they're not seriously using this to filter out applicants.
It was implied. Could have been explicit, though!
@@LukeSumIpsePatremTe Various implications would make it ambiguous
Yeh, unnecessarily confusing setup for sure.
I mean instead of staying silent they could just have responded "no" which indicates they're finished accessing and have decided that they don't know. The problem is that the first to answer gives the second more information so instead, they remain silent and we're asked to assume if they needed more time they would have said so lol
I was not even thinking about that part and I still solved it. I think is moré like a guide on how many discard steps there was(???
This proves a point, it's important to have an eye on not only your own move but also on the move of the competitors.
They are not competitors, your point is not valid.
This problem does not work at all. What is the justification for claiming that silence means the same as "No"? Silence could mean "Yes, but I am not telling." or "No, but I am not telling." or even something else.
That's what Game Theory is
@@urfinjuice1437 That's why Both Shilpa and Colin are said to be perfect logicians, and there is no indication that they are antagonistic towards each other. The basis of this problem is what is known as "Common Knowledge", meaning that you gain knowledge from knowing what others with different information know. If both Shilpa and Colins refuse to speak on the grounds of competition (which were not established) then logically they would never say anything since they gain no new information (and it would benefit their competitor) and thus cannot solve the puzzle.
@@williamschwarer2463 Thank you for your answer. It is not logical though. There is not reason to claim that Shilpa and Colin do not answer because they are antagonitic or competitive. They just do not answer. Noone knows the reason. As a result, noone except each one for themselves can know what they know. So "Common Knowledge" does not help. It is just a flaw in the puzzle. It is not properly thought through.
I actually did it!! First problem on this channel that I’m able to solve!
I do not equate silence to "I don't know." I initially read silence as "I know, but don't want to give the answer away," which cost me a few moments before I managed to solve the puzzle.
Got it, took about 3 mins. If I'm genuinely a genius then humanity is setting the bar pretty freaikin' low..
maybe you are a logical genius...trying be a genius in the other 7 intelligence departments as well
I am absolutely not a genius but still solved it in my head immediately. It's not difficult logic to follow at all
Now assume that they don't know each other's answers.
To Oxford you go!
Lies
I didn't pause the video to try to solve it, but after I watched the video I don't think I would've got it anyways. But I need to watch more videosof this guy so I can learn this kind of rational thinking! :)
Thats how idiots like Imran Khan went to Oxford and Sonia Gandhi & Rajiv Gandhi went to Cambridge.
At a glance I would suggest a Yellow triangle on the right, however I have not read the question yet ! Look forward to watching.
so glad I got this right, I feel better about my chances
The feeling of getting it right is unmatched
Truly
One of the few problems that I actually managed to solve on my own wow
Lol same
Me too
Same here
Me too. So proud
Easy pisy
Awesome puzzle. Subscribed.
Robots are taking the planet over right in front of us: 5:04 “What A Fun Logic Puzzle.”