Logic riddles challenge! [Archive]

kehmesis

07-05-2008, 09:57 PM

I hope we have riddles fans in here.

If you are, like me, a riddle fan, I challenge you! You must answer my riddles. Failure to do so will result in... well, nothing, sadly. But success will bring... well... hmmmm. Anyway, let's start!

Rules:

1. All you need to know is written down. There are no super godly tricks. They are logic riddles, not "find a loophole bullshit solution" riddles.

2. PM me the solution OR spoiler them. Don't post the answer for all others to see, that's pretty lame. Someone probably will anyway, but at least we'll see who the fastest asshole is :)

3. Post your own? I will find them.

You can ask questions if you are not sure you understand the riddle. I will not give hints nor solutions, however.

#1. Four friends

Four friends are held prisoners by an evil wizard. They are stuck in hard mud from feet to shoulder. Only their heads are sticking out. The only way to escape is if one of the four friends guesses the color of his own hat. They know that there are 2 white hats and 2 black ones, but do not know who has which. If they speak for any other reasons than to say the color of their own hat, they all die.

After a few minutes, one of them speaks and say the color of its own hat out loud. They are all freed. He was absolutely certain of his answer (he was not guessing). Which one is it, and how did he figure it out?

http://img392.imageshack.us/img392/7278/4friendsqe1.jpg (http://img392.imageshack.us/my.php?image=4friendsqe1.jpg)

In case you don't get it, the first one on the left sees nothing but a wall. The 2nd guy sees nothing but a wall. The 3rd guy can see the 2nd guy's hat. And the last guy can see the 2nd and 3rd guy's hat.

--------------

#2. The fucked up religion

A community lives on an island, far from civilization. They have a very weird religion: if one knows the color of his own eyes, he must commit suicide before the next day. And while you can see everyone's eye color, you must not tell anyone what color their eyes are. However, they are all very logical and have the same reasoning, so if they can figure out the color of their own eyes, they will. There are no mirrors and they cannot see the reflection of their eyes in water or any other bullshit.

One day, a stranger comes to the island and says: "At least one of you has blue eyes." He then leaves.

Now, what happens if there is only one person on the island with blue eyes? He will see that no one has blue eyes, and logically deduce that he must be the one to have blue eyes. So he will kill himself before the next day.

What if two people have blue eyes? The first day, they will both think that the other will kill himself before the next day. But the 2nd day, seeing that the blue eyed person didn't kill himself, he will logically deduce that they also have blue eyes and both will kill themselves before the next day.

What if three people have blue eyes? The 3rd day, seeing that the two other people with blue eyes didn't kill themselves, he will logically deduce that they also must have blue eyes, so they will all kill themselves before the next day.

And so on. (If you don't get this, get a pen and paper and work on it! It is vital that you understand and agree this is what would happen.)

Now, let's say there were 10 people with blue eyes in total. Everyone on the island already knew that at least one of them had blue eyes. So they actually didn't learn anything new from the stranger.

So that creates a paradox:

1. They didn't kill themselves before the stranger came.
2. They started killing themselves after the stranger came.
3. They didn't learn anything new from the stranger.

One of these affirmation MUST be wrong. Which one is it?

If you pick #1 or #2, you must explain why they did or did not kill themselves before/after the stranger came. If you pick #3, you must explain what new information they learned from the stranger.

---------

#3.

I have a third one, but I'll give it only to those able to find the first 2 ones.

Have fun, and good fuckin' luck.

Forgin

07-05-2008, 10:04 PM

the first one is easy, second one takes to much thinking

ExiliuM

07-05-2008, 10:05 PM

The first one is driving me crazy. I have no idea but I bet the answer is simple as shit

Satan

07-05-2008, 10:17 PM

1.
the third guy knows the color of his hat because if the last guy doesnt know his color then the guy in front of him must not have the same color hat as he does. therefore his hat is the opposite color

Spades Felligan

07-05-2008, 10:22 PM

Second one sounds awesome, I'm going to have to sleep on that.

ExiliuM

07-05-2008, 10:23 PM

Apex Vertigo

07-05-2008, 10:24 PM

1st one is easy, 2nd one... I'll come back to later because the three people killing themselves part is not making sense atm.

1st Riddle Spoiler... Just to tempt you.

The answer is : The 3rd guy realizes his hat is white and says it out loud.
Explanation: The 3rd guy can see the 2nd guys hat and knows that hat is black, meaning there is 1 black and 2 whites left unknown. The guy behind him has a black hat and can see 2, leaving a white and a black left, but says nothing because he obviously doesn't know the answer. The third guy will deduct that the 4th doesn't know the answer even though he can see the other 2 meaning the 2 he can see must be of different color. He already knows the 2nd is black, meaning he can't be black or the 4th would had already found the answer, leaving him with white.

*This is only right if the 3rd guy knows the 4th guy is behind him... if not then I am wrong.

Teutates

07-05-2008, 10:26 PM

omnigol

07-05-2008, 10:28 PM

Technically this is not a spoiler although it would soon become one in anyones mind, if I am right. This situation highlights why I don't like these 'logic' puzzles, as they tend to depend on details that make it too obvious if you mention them specifically. Yet they need to be known, or assumed for the puzzle to be solved.

My question for the first one is: Does the 3rd guy know the 4th guy is behind him and able to see his hat?

I think this puzzle comes with the diagram, and counts on the audience assuming the 4 guys know the information given in the diagram, but not the color of the hats. Even though they can talk.

Spades Felligan

07-05-2008, 10:28 PM

Is it possible that the stranger is lying? Or can the natives tell others what eye color their eyes are NOT?

Spades Felligan

07-05-2008, 10:33 PM

Nevermind

Viluin

07-05-2008, 10:38 PM

Satan

07-05-2008, 10:45 PM

Spades Felligan

07-05-2008, 10:47 PM

Everyone lives if there is at least two people with blue eyes. Because everyone can see AT LEAST one person with blue eyes, non-blued eye people will see two people with blue eyes. In that case, nothing new has been learned from the stranger.

The only time anyone can learn anything new from the stranger is if only one person has blue eyes. Everyone else already knows this, except for the blue eyed person, therefore that person will then kill her/himself.

So #2 is wrong

Viluin

07-05-2008, 10:49 PM

What I said earlier was wrong.

#1 has to be correct, otherwise there wouldn't be anyone with blue eyes left for the stranger to mention. #3 is correct because the story says so. #2 must be wrong.

Only solution.

Teutates

07-05-2008, 10:50 PM

#1
Is impossible in my eyes, only if you give more information.

Spades Felligan

07-05-2008, 10:53 PM

It's simple if you draw a diagram of the villagers.

Lachrymose

07-05-2008, 11:09 PM

Spades Felligan

07-05-2008, 11:15 PM

#2
The first two must be true if the reasoning described is accurate, so the 3rd is false.

They already knew that at least one person had blue eyes, but after being told that, they can also deduce that at least one person will kill themselves, being that it's possible for them to figure out they have blue eyes, and it was stated if it's possible to figure out, they will figure out.

Therefore, if everyone knows at least one person will kill themselves, when they see that no one has, they each individually know it must be them that should kill themselves and b/c they have the same reasoning, they would each figure it out at the same time, so they would all end up killing themselves at the same time.

No, no, no. It works like this.

Case 1: The number of blue-eyed people are at least 1.

If there is one blue-eyed person, then everyone else but that person already knows that there is at least one blue-eyed person. The blue-eyed will find this to be new information, and kill himself because everyone else has non-blue eyes. Problem solved.

Case 2: If there are more than one blue-persons, then nobody kills themselves because everyone already knows that there is at least one blue-eyed person.

If there are two or more blue eyed people, the blue eyed people observe each other's eyes, find them to be blue, and thus fullfills the truth that AT LEAST one person is blue eyed, nothing more happens.

Lachrymose

07-05-2008, 11:21 PM

No, no, no. It works like this.

Case 1: The number of blue-eyed people are at least 1.

If there is one blue-eyed person, then everyone else but that person already knows that there is at least one blue-eyed person. The blue-eyed will find this to be new information, and kill himself because everyone else has non-blue eyes. Problem solved.

Case 2: If there are more than one blue-persons, then nobody kills themselves because everyone already knows that there is at least one blue-eyed person.

If there are two or more blue eyed people, the blue eyed people observe each other's eyes, find them to be blue, and thus fullfills the truth that AT LEAST one person is blue eyed, nothing more happens.

but....

just like it expliains... if there are, say 2 blue eyes, bill and ted. at first bill will think "i'm ok, b/c ted has blue eyes, so i already knew that there was one blue eyed person." but when ted doesn't kill himself, bill can deduce that ted is thinking the same thing becasue someone else must have blue eyes, and knowing that it isn't anyone else, bill realizes it must be himself, so w/ 2 blue eyed ppl, they can figure out they have blue eyes themselves. ted will also deduce the same thing from his pov, and kill himself too.

Spades Felligan

07-05-2008, 11:29 PM

but....

just like it expliains... if there are, say 2 blue eyes, then at first one will think "i'm ok, that other guy has blue eyes, so i already knew that there was one blue eyed person." but when that person doesn't kill themselves, they can deduce that that person is thinking the same thing becasue someone else has blue eyes, and knowing that it isn't anyone else, it must be them, so w/ 2 blue eyed ppl, they can figure out they have blue eyes themselves.

But they already know that at least one person has blue eyes. Each other. Get it? The stranger said that at least one person has blue eyes, the fact that they already have beforehand observed each other having blue eyes makes that statement already known to each other.

Put yourself into the shoes of a non-blue eyed person or a blue-eyed person in that scenario. Whether or not you're blue eyed, you'll always going to see at least one other person with blue eyes. But you'll never know your own eye color. So as long everyone can observe at least one person with blue eyes, nobody dies.

Nobody can logically deduce that themself do or do not have blue eyes, even if they can see both blue eyed people, because the stranger said at least one, which mean 1,2,3...and so on. So there's always the possibility that you may yourself have blue eyes. Even though in reality, it may only really be two other people.

So you can never, ever be sure that you have blue eyes in this situation. Due to the fact that you cannot observe your own eye color, there will always be uncertainty.

It's really only possible to be sure if only one person has blue eyes, because then he would kill himself, observing no-one else having blue eyes.

Viluin

07-05-2008, 11:30 PM

Sorry, but my second answer is the only right one. Its logic is infallible. I dare you to try it. You guys are giving this way too much thought.

Ftang

07-05-2008, 11:37 PM

Sorry, but my second answer is the only right one. Its logic is infallible. I dare you to try it. You guys are giving this way too much thought.
your answer is wrong because the "story confirms 3" is not true for the entire problem. just the "if there were 10" scenario.

my answer:

1. this must be true because no blue eyes left otherwise.
2. this must be true because the information "atleast one of you has blue eyes" will always lead to all blue eyes dying.
3. this must then be false. only one person had blue eyes. so the stranger gave him new information.

Lachrymose

07-05-2008, 11:38 PM

But they already know that at least one person has blue eyes. Each other. Get it? The stranger said that at least one person has blue eyes, the fact that they already have beforehand observed each other having blue eyes makes that statement already known to each other.

Put yourself into the shoes of a non-blue eyed person or a blue-eyed person in that scenario. Whether or not you're blue eyed, you'll always going to see at least one other person with blue eyes. But you'll never know your own eye color. So as long everyone can observe at least one person with blue eyes, nobody dies.

Nobody can logically deduce that themself do or do not have blue eyes, even if they can see both blue eyed people, because the stranger said at least one, which mean 1,2,3...and so on. So there's always the possibility that you may yourself have blue eyes. Even though in reality, it may only really be two people.

It's really only possible to be sure if only person has blue eyes, because then he would kill himself, observing no-one else having blue eyes.

yea, but it's just like in the first riddle.. the 3rd dude knows that he has a black hat, b/c if him and the guy in front had the same color hat, the guy behind him would have figured out which color he has.

in this one, if 2 ppl have blue eyes, then sure, they will both know that at least one person has blue eyes. but, from their pov, ONLY one person has blue eyes. if that's the case, it's like u said, that one person would figure it out and kill themselves. but, if you were one of the ppl w/ blue eyes, if you noticed the other guy hadn't killed himself yet, you can logically deduce that he didn't kill himself b/c he doesn't think he's the one w/ blue eyes, meaning someone ELSE has blue eyes, and if you know that no one else besides him has blue eyes, then you must be the other person w/ blue eyes. :ohno: he of course comes to the same conclusion, you both off yourselves.

Viluin

07-05-2008, 11:39 PM

your answer is wrong because the "story confirms 3" is not true for the entire problem. just the "if there were 10" scenario.

my answer:

1. this must be true because no blue eyes left otherwise.
2. this must be true because the information "atleast one of you has blue eyes" will always lead to all blue eyes dying.
3. this must then be false. only one person had blue eyes. so the stranger gave him new information.

The examples of 1, 2 and 3 people with blue eyes were just that, examples. The riddle is only about the "if there were 10" scenario. My answer must be correct or the riddle is flawed.

Lachrymose

07-05-2008, 11:41 PM

The examples of 1, 2 and 3 people with blue eyes were just that, examples. The riddle is about the "if there were 10" scenario. My answer must be correct or the riddle is flawed.

yea, but if examples 1, 2, and 3 are true, logical induction says that anything above 3 would also be true, assuming the same pattern is repeated.

Spades Felligan

07-05-2008, 11:44 PM

yea, but it's just like in the first riddle.. the 3rd dude knows that he has a black hat, b/c if him and the guy in front had the same color hat, the guy behind him would have figured out which color he has.

in this one, if 2 ppl have blue eyes, then sure, they will both know that at least one person has blue eyes. but, from their pov, ONLY one person has blue eyes. if that's the case, it's like u said, that one person would figure it out and kill themselves. but, if you were one of the ppl w/ blue eyes, if you noticed the other guy hadn't killed himself yet, you can logically deduce that he didn't kill himself b/c he doesn't think he's the one w/ blue eyes, meaning someone ELSE has blue eyes, and if you know that no one else besides him has blue eyes, then you must be the other person w/ blue eyes. :ohno: he of course comes to the same conclusion, you both off yourselves.

It would be a lot easier to follow your logic if you typed proper grammar.

If that were the case, then everyone would off themselves. You have to remember that everyone would have the same experience, meaning everyone would make the assumption that they also have blue eyes.

Meaning all three cases are correct.

I edited it guys, so if you just read it, check it again.

Ftang

07-05-2008, 11:45 PM

The examples of 1, 2 and 3 people with blue eyes were just that, examples. The riddle is only about the "if there were 10" scenario. My answer must be correct or the riddle is flawed.

i too interepreted it in that way initiatially. i would say it is a wording issue. if we know there are 10 then the riddle is too easy. it also makes no sense that one 3rd of the answer would be given away like that. the number of blue eyes must be unknown

Lachrymose

07-05-2008, 11:47 PM

It would be a lot easier to follow your logic if you typed proper grammar.

If that were the case, then everyone would off themselves. You have to remember that everyone would have the same experience, meaning everyone would make the assumption that they also have blue eyes.

Meaning all three cases are correct.

I edited it guys, so if you just read it, check it again.

that's where the problem comes in.. NOT everyone would off themselves b/c from their POV, they would know that 2 ppl had blue eyes, not just 1. then, just as i said last time, the 2 ppl would kill themselves and everyone else would be just fine. the ONLY people that realizes there are not just 1, but 2 blue eyed people, are the blue eyed people themselves. everyone else ALREADY knows there are 2 blue-eyed people.

Viluin

07-05-2008, 11:48 PM

i too interepreted it in that way initiatially. i would say it is a wording issue. if we know there are 10 then the riddle is too easy. it also makes no sense that one 3rd of the answer would be given away like that. the number of blue eyes must be unknown

If there is more than 1 person with blue eyes, the stranger would indeed provide no new information. That means #3 is only correct in some cases which just doesn't work. The amount of people with blue eyes has to be fixed, in this case 10.

Ftang

07-05-2008, 11:50 PM

If that were the case, then everyone would off themselves. You have to remember that everyone would have the same experience, meaning everyone would make the assumption that they also have blue eyes.

Meaning all three cases are correct.
you mean everyone as in everyone on the island? that may make sense when you apply your own logic, however we have already been told how that situation must be resolved within this scenario. it takes x days for x blue eyes to realise they have to kill themselves, and then only they will.

Lachrymose

07-05-2008, 11:50 PM

who posted this tread? just tell us the answers already :eek:

Lachrymose

07-05-2008, 11:51 PM

you mean everyone as in everyone on the island? that may make sense when you apply your own logic, however we have already been told how that situation must be resolved within this scenario. it takes x days for x blue eyes to realise they have to kill themselves, and then only they will.

qft

Spades Felligan

07-05-2008, 11:51 PM

that's where the problem comes in.. NOT everyone would off themselves b/c from their POV, they would know that 2 ppl had blue eyes, not just 1. then, just as i said last time, the 2 ppl would kill themselves and everyone else would be just fine.

But, a person can't assume that it's only those two blue eyed people that stopped them from committing suicide. They may have seen a third person with blue eyes, you.

You may be right, in that case, the two people scenario would follow into Case 2, as I previously mentioned. I'm not entirely convinced yet though, I'm pretty tired. :/

Ftang

07-05-2008, 11:55 PM

If there is more than 1 person with blue eyes, the stranger would indeed provide no new information. That means #3 is only correct in some cases which just doesn't work. The amount of people with blue eyes has to be fixed, in this case 10.
3 questions are provided and one must be false. therefore if we can conclude 2 are correct then the 3rd is determined as false. in my interpretation where 10 blue eyes is just another example and the answer of 3 is not pre-determined, 1 and 2 must be correct, leaving 3 as incorrect. only one islander has blue eyes. there is no different possibilities because of the nature of the 3 questions provided.

Lachrymose

07-06-2008, 12:00 AM

But, a person can't assume that it's only those two blue eyed people that stopped them from committing suicide. They may have seen a third person with blue eyes, you.

You may be right, in that case, the two people scenario would follow into Case 2, as I previously mentioned. I'm not entirely convinced yet though, I'm pretty tired. :/

exactly, that's why, in the case of 3 blue eyed ppl, you'll realize that the other 2 haven't killed themselves yet. so you'll know that there must be a 3rd person w/ blue eyes (there can't be a 4th b/c you know that there must be either 2 or 3 with blue eyes, 3 if you yourself have blue eyes). that's why it's important to note that all the people have the same exact reasoning process.

Spades Felligan

07-06-2008, 12:01 AM

Man, I am so fucking confused now. I *think* my logic holds for situations above 2 person situations.

Let me sleep on it.

Spades Felligan

07-06-2008, 12:14 AM

Now, let's say there were 10 people with blue eyes in total. Everyone on the island already knew that at least one of them had blue eyes. So they actually didn't learn anything new from the stranger.

So that creates a paradox:

1. They didn't kill themselves before the stranger came.
2. They started killing themselves after the stranger came.
3. They didn't learn anything new from the stranger.

Okay, in this case, #2 is wrong. Simply because you can see 9 people with blue eyes beforehand, that's fucking easy.

But 2-3 people, I'm not so sure.

Lachrymose

07-06-2008, 12:22 AM

if it works for 3 ppl, it works for 9 ppl b/c the inductive logic is the same.

Ftang

07-06-2008, 12:27 AM

Okay, in this case, #2 is wrong. Simply because you can see 9 people with blue eyes beforehand, that's fucking easy.

But 2-3 people, I'm not so sure.
as ive said before.. its the same for all numbers above 1. x blue eyes = x days until they work out they have blue eyes and kill themselves. this is the logic we are told we must work with.

also where is kehmesis to tell me if my answer is right :(

Ample

07-06-2008, 02:26 AM

Viluin

07-06-2008, 02:47 AM

my head hurts from #2, so i've got 2 more riddles that you guys can play with that are on the same difficulty level as #1 (or so i think)...

1.
You are in an attic with 3 light switches that each turn on 3 different lights in the basement.
You want to find which light switch turns on which light bulb.
You can only go down into the basement once, and you cannot come back up.

You turn on two switches and wait a few minutes. Then you turn one switch off again. When you go down the basement, you'll have:

- A light bulb that's turned on (Turned on by the switch you left on, obviously)
- A light bulb that's off but still hot (Turned on by the switch you turned on then off)
- A light bulb that's off and cold (turned on by the switch you never touched)

2.
You are in a completely closed in room, with no clocks.
All you have are 2 pieces of rope and a means of setting them on fire.
Each rope burns for 1 hour each, they do not burn at the same rate. (for example you cannot cut the rope into 1/4ths and each will burn for 15 min... for all you know, 95% of the rope could be burned in 5 minutes and the last 5% of the rope could take 55 minutes. But you don't know, all you do know is that each rope burns for 1 hour)
You need to use the ropes to (for lack of a better word) "count" 45 minutes and you will be set free.
(before anyone asks..... ropes can only be burned once and counting 1... 2... 3... in your head obviously does not work)

Impossible imo. You can make a rope burn half an hour by lighting both ends on fire but I don't see how you could ever count another 15 minutes to get 45..

Unahim

07-06-2008, 03:08 AM

my head hurts from #2, so i've got 2 more riddles that you guys can play with that are on the same difficulty level as #1 (or so i think)...

1.
You are in an attic with 3 light switches that each turn on 3 different lights in the basement.
You want to find which light switch turns on which light bulb.
You can only go down into the basement once, and you cannot come back up.

This one is pretty mainstream... bit too easy.

2.
You are in a completely closed in room, with no clocks.
All you have are 2 pieces of rope and a means of setting them on fire.
Each rope burns for 1 hour each, they do not burn at the same rate. (for example you cannot cut the rope into 1/4ths and each will burn for 15 min... for all you know, 95% of the rope could be burned in 5 minutes and the last 5% of the rope could take 55 minutes. But you don't know, all you do know is that each rope burns for 1 hour)
You need to use the ropes to (for lack of a better word) "count" 45 minutes and you will be set free.
(before anyone asks..... ropes can only be burned once and counting 1... 2... 3... in your head obviously does not work)

You light one rope from one end and the other from both ends.
When the one you lit from both ends burns up, you know half an hour has passed.
You now light the other rope, which you had originally lit only from one end, on the other end as well.
Seeing as that cuts the remaining time(30 minutes) in half, you get a total of 45 minutes on that rope.

Personally I wouldn't light a fire in an enclosed space though, certainly not for 45 minutes(oxygen ftl)

Viluin

07-06-2008, 03:41 AM

Wow.

http://www.borrett.id.au/computing/petals-j.htm

Someone try to solve this. It's driving me nuts.

kehmesis

07-06-2008, 04:06 AM

OK guys, sorry for the late update.

Many found #1. It's the easiest, but it's no way easy. Many people never figure it out. So congrats if you did!

There is a small tiny flaw in that riddle. It's a math thing and it's a bit complicated. However, It should definitely not keep you from finding the answer. It's about timing and stuff. You also have to assume that your friends are not total morons, as most of you did.

-------

#2. A tip: Try and really understand why they couldn't possibly kill themselves before, that they could definitely kill each other after, and figure out why. That might tell you what the new information is

Ftang: It works for all situations. Obviously, if there is only 1 person, then you are right, it was new information. But if there was 2, or 10, or a thousand, it stops working. Let's suppose there are 10 of them. They would kill each other after, not before, but what was the new information then?

----

It's a little hard for me to answer everyone by reading the forums. If you absolutely want a personal answer, PM me.

I'm re-reading the thread and I'll try to answer a few questions. Coming soon...

kehmesis

07-06-2008, 04:26 AM

but....

just like it expliains... if there are, say 2 blue eyes, bill and ted. at first bill will think "i'm ok, b/c ted has blue eyes, so i already knew that there was one blue eyed person." but when ted doesn't kill himself, bill can deduce that ted is thinking the same thing becasue someone else must have blue eyes, and knowing that it isn't anyone else, bill realizes it must be himself, so w/ 2 blue eyed ppl, they can figure out they have blue eyes themselves. ted will also deduce the same thing from his pov, and kill himself too.

Spades and Lachrymose, Lach is correct here.

If 2 people have blue eyes, seeing that they other didn't kill himself the next day, they will both kill themselves on that day, and nobody else will kill themselves afterwards because they will now know there were only 2 people with blue eyes.

If 3 have blue eyes, they will each see that the 2 people with blue eyes didn't kill themselves after the 2nd day (unlike the situation above), so there must be a 3rd one. Everyone on the island saw 3 blue-eyed persons, besides the 3 that actually have blue eyes, who saw only 2.

That's why only N people will kill themselves after N days. No more, no less.

Ftang

07-06-2008, 04:33 AM

#2. Ok, first of all, Lachrymose and Ftang have got the logic right. You understand the puzzle, you probably know the answer, but can't put it into words.

A tip: Try and really understand why they couldn't possibly kill themselves before, that they could definitely kill each other after, and figure out why. That might tell you what the new information is

Ftang: It works for all situations. Obviously, if there is only 1 person, then you are right, it was new information. But if there was 2, or 10, or a thousand, it stops working. Let's suppose there are 10 of them. They would kill each other after, not before, but what was the new information then?

Lachrymose: I think you figured it out afterwards, but they can't all kill themselves at the same time because only those with blue eyes see 1 less than everyone else, who would need to wait 1 day.
they cant kill themselves before because they have no indication at all as to their eye colour just from looking at each others eyes (ignoring genetics). the stranger gives the information that atleast one person definitely has blue eyes. this creates the example situation whereby any blue eyed person will know for sure they have blue eyes when a number of days equal to the number of blue eyed people they can see has been reached without suicide. meaning the true number of blue eyed people is how many they can see +1 (themselves).

thats rehashing what ive already said i guess. i dont know how to put it differently.

im kind of confused now as you seem to agree that 1 and 2 are true, but for numbers greater than 1 blue eyed person the riddle stated that 3 is true.

kehmesis

07-06-2008, 04:50 AM

#2

Everyone on the island already knew that at least one of them had blue eyes. So they actually didn't learn anything new from the stranger.

^ Because of this information, the third affirmation must be correct otherwise the entire riddle is BS. The second affirmation must be wrong, because if nothing changed with the stranger's appearance then they shouldn't suddenly start killing themselves after he appears.

It's either this or I call BS on the riddle.

You're wrongfully assuming that one of the statement is true, which leads you to believe that another one is true, making the third one false. That's not the task you've been asked to do.

Also, something did change with the stranger's appearance, and I've explained it very clearly: those with blue eyes kill eachother after the N day, N being the number of people with blue eyes.

kehmesis

07-06-2008, 04:57 AM

they cant kill themselves before because they have no indication at all as to their eye colour just from looking at each others eyes (ignoring genetics). the stranger gives the information that atleast one person definitely has blue eyes. this creates the example situation whereby any blue eyed person will know for sure they have blue eyes when a number of days equal to the number of blue eyed people they can see has been reached without suicide. meaning the true number of blue eyed people is how many they can see +1 (themselves).

thats rehashing what ive already said i guess. i dont know how to put it differently.

im kind of confused now as you seem to agree that 1 and 2 are true, but for numbers greater than 1 blue eyed person the riddle stated that 3 is true.

First, forget the situation where there is only 1 blue eyed person. It must work for any number of blue eyed persons. Did not mean to confuse you. In the case where there are more than 1 person (I've randomly picked 10 in the riddle), a paradox happens, because the 3 statements can't be true, there MUST be one that is false.

Now, you got the logic right so far. If #3 is false, it means that the stranger gave them new information. You haven't answered that question yet, you've only told me what the riddle already said: they will kill themselves after N days, N being the number of blue eyed persons on the island.

In other words, you're saying that they can't possibly kill each other before the stranger told them there was at least one person with blue eyes. Why exactly? They already knew there was at least one person with blue eyes.

kehmesis

07-06-2008, 05:03 AM

Okay, in this case, #2 is wrong. Simply because you can see 9 people with blue eyes beforehand, that's fucking easy.

But 2-3 people, I'm not so sure.

In the situation where there are 10 people, they would all kill themselves after 10 days, because the 9 people they saw with blue eyes didn't kill themselves after the 9th day.

Just like when there are 2 people with blue eyes, they will both kill themselves on the 2nd day when they see that the one person they see with blue eyes didn't kill himself on the first day.

Just like when there are 3 people with blue eyes, they will all kill themselves on the 3rd day when they see that the 2 people with blue eyes didn't kill themselves on the 2nd day.

And so on.

Those without blue eyes will never kill themselves because they see one more person with blue eyes than those with blue eyes.

Ftang

07-06-2008, 05:05 AM

First, forget the situation where there is only 1 blue eyed person. It must work for any number of blue eyed persons. Did not mean to confuse you. In the case where there are more than 1 person (I've randomly picked 10 in the riddle), a paradox happens, because the 3 statements can't be true, there MUST be one that is false.

Now, you got the logic right so far. If #3 is false, it means that the stranger gave them new information. You haven't answered that question yet, you've only told me what the riddle already said: they will kill themselves after N days, N being the number of blue eyed persons on the island.

In other words, you're saying that they can't possibly kill each other before the stranger told them there was at least one person with blue eyes. Why exactly? They already knew there was at least one person with blue eyes.

according to the wording of the riddle, for N > 1, question 3 is true. if this is not supposed to be the case then the riddle has been misworded to an extremely confusing degree

kehmesis

07-06-2008, 05:09 AM

according to the wording of the riddle, for N > 1, question 3 is true. if this is not supposed to be the case then the riddle has been misworded to an extremely confusing degree

No, that's the actual riddle. I'm saying they did not learn anything from the stranger, but it might be false. One of the statements must be false, even though all of them seem to be true.

If #3 is false, which it is, you must find what new information they gained from the stranger, eventhough it looks like they didn't.

Lachrymose

07-06-2008, 05:27 AM

kehmesis

07-06-2008, 05:29 AM

my head hurts from #2, so i've got 2 more riddles that you guys can play with that are on the same difficulty level as #1 (or so i think)...

1.
You are in an attic with 3 light switches that each turn on 3 different lights in the basement.
You want to find which light switch turns on which light bulb.
You can only go down into the basement once, and you cannot come back up.

You turn #1 on. You turn #2 on. Wait a few minutes. You close #2 off. Go downstairs and touch the 2 lights that are off.

2.
You are in a completely closed in room, with no clocks.
All you have are 2 pieces of rope and a means of setting them on fire.
Each rope burns for 1 hour each, they do not burn at the same rate. (for example you cannot cut the rope into 1/4ths and each will burn for 15 min... for all you know, 95% of the rope could be burned in 5 minutes and the last 5% of the rope could take 55 minutes. But you don't know, all you do know is that each rope burns for 1 hour)
You need to use the ropes to (for lack of a better word) "count" 45 minutes and you will be set free.
(before anyone asks..... ropes can only be burned once and counting 1... 2... 3... in your head obviously does not work)

I like it. Working on this one as soon as I'm done with the fuckin' roses.

kehmesis

07-06-2008, 05:34 AM

so is the answer that they learn (or rather, they can logically deduce from the new information) that in N days, the blue eyed people will kill themselves? where N is the number of blue eyed people. That way, when a blue eyed person sees that 9 people are still alive after 9 days, they know there must be a 10th, and it must be themselves.

I don't really feel like that's something that's isn't already stated tho. :(

Exactly. That's already stated.

Let me ask you this: why did they need the stranger to tell them there was at least 1 blue eyed person on the island for the thought process (that you are describing) to kick off since they already knew that there was already 1 person with blue eyes.

Beeblebrox

07-06-2008, 05:43 AM

This thread is gonna end in a bloodbath.

Or brain tumor.

Lachrymose

07-06-2008, 05:45 AM

:bang:

kehmesis

07-06-2008, 06:29 AM

You are in a completely closed in room, with no clocks.
All you have are 2 pieces of rope and a means of setting them on fire.
Each rope burns for 1 hour each, they do not burn at the same rate. (for example you cannot cut the rope into 1/4ths and each will burn for 15 min... for all you know, 95% of the rope could be burned in 5 minutes and the last 5% of the rope could take 55 minutes. But you don't know, all you do know is that each rope burns for 1 hour)
You need to use the ropes to (for lack of a better word) "count" 45 minutes and you will be set free.
(before anyone asks..... ropes can only be burned once and counting 1... 2... 3... in your head obviously does not work)

You start burning rope #1 on one end and at the same time you start burning rope #2 on both ends. When rope number 2 is done, 30 minutes has passed. You light the other end of rope #1, which will then burn in exactly 15 minutes, for a total of 45 minutes.

Bawlin

07-06-2008, 06:32 AM

Exactly. That's already stated.

Let me ask you this: why did they need the stranger to tell them there was at least 1 blue eyed person on the island for the thought process (that you are describing) to kick off since they already knew that there was already 1 person with blue eyes.

They needed him so that they could question whether or not their eye color was blue, so in fact they learned their own eye color using logic in relation to all the other blue eyed people, them killing themselves, etc. But he began the chain by stating there was ATLEAST one

kehmesis

07-06-2008, 06:33 AM

Wow.

http://www.borrett.id.au/computing/petals-j.htm

Someone try to solve this. It's driving me nuts.

Very hard. I think I'm getting close, though. I'm getting one out of 4 right at the moment from the patterns only.

I'll break it eventually, I'm sure. But I've had enough for tonight.

Komako

07-06-2008, 06:57 AM

You could probably get away with hiding porn in this thread

Viluin

07-06-2008, 01:39 PM

Also, something did change with the stranger's appearance, and I've explained it very clearly: those with blue eyes kill eachother after the N day, N being the number of people with blue eyes.

But that's not the third affirmation. The third affirmation is that the people learned something new from the stranger, which they didn't. The third affirmation must be correct.

Teutates

07-06-2008, 02:13 PM

eek nm misread

Suitepee

07-06-2008, 02:13 PM

Darkfall:

-Where is it?

Serious Time:

-I am the symbol of death but also life. What am I?

Unahim

07-06-2008, 03:31 PM

Darkfall:

-Where is it?
Athens

Serious Time:

-I am the symbol of death but also life. What am I?

An old man: the symbol of life because it clearly shows how life is keeping this old wreck together, and death because we all know how soon it's going to fall apart.

kehmesis

07-06-2008, 04:41 PM

But that's not the third affirmation. The third affirmation is that the people learned something new from the stranger, which they didn't. The third affirmation must be correct.

You assume that they didn't, because it looks like they didn't. But you might be wrong.

You are. They learn new information from the stranger. Find what it is.

Suitepee

07-06-2008, 04:56 PM

An old man: the symbol of life because it clearly shows how life is keeping this old wreck together, and death because we all know how soon it's going to fall apart.

I was actually thinking of blood,but then again I pretty much made it up on the spot. I guess that works well too. :)

-Eight men are gathered together in a remote desert. They are waiting for something. After a time the drone of a plane is heard. It approaches, and eventually a light aircraft comes into view. It circles the eight men, banks, comes down closer. A door opens in the side of the plane, a package is thrown out, and the plane flies off into the distance. The eight men run to the package and examine it. It turns out to be a human arm, neatly wrapped in surgical dressings and outer packaging. They look at it, look at one another, nod their satisfaction; then they bury the arm in the deserrt sand, and go their separate ways - as far as we know, not to meet again.

In a very exclusive bar in New York two men meet. One of them is an eminent surgeon, the other nobody in particular. The surgeon presents the other with a banker's cheque for half a million dollars. The other man examines it, expresses his satisfaction, and they part.

Viluin

07-06-2008, 05:50 PM

You assume that they didn't, because it looks like they didn't. But you might be wrong.

You are. They learn new information from the stranger. Find what it is.

The riddle literally states they did not learn anything new from the stranger.

kehmesis

07-06-2008, 06:42 PM

The riddle literally states they did not learn anything new from the stranger.

Yes, the riddle makes 3 statements. But one of them is false and you must find out which.

The riddles says that if there was 10 blue-eyed persons on the island (it works for 2 or more), everyone already knew that there was at least one person with blue eyes. That's obvious.

But that doesn't mean they didn't get new information. They needed the stranger to say this for the process of killing themselves to happen. Why? What new information did they get from the stranger's statement top kick off the process?

kehmesis

07-06-2008, 06:45 PM

-Eight men are gathered together in a remote desert. They are waiting for something. After a time the drone of a plane is heard. It approaches, and eventually a light aircraft comes into view. It circles the eight men, banks, comes down closer. A door opens in the side of the plane, a package is thrown out, and the plane flies off into the distance. The eight men run to the package and examine it. It turns out to be a human arm, neatly wrapped in surgical dressings and outer packaging. They look at it, look at one another, nod their satisfaction; then they bury the arm in the deserrt sand, and go their separate ways - as far as we know, not to meet again.

In a very exclusive bar in New York two men meet. One of them is an eminent surgeon, the other nobody in particular. The surgeon presents the other with a banker's cheque for half a million dollars. The other man examines it, expresses his satisfaction, and they part.

Is this just a cool story or... ?

Incanam

07-06-2008, 06:46 PM

Is this just a cool story or... ?

Yeah, what's the riddle here?

Unahim

07-06-2008, 06:48 PM

I was actually thinking of blood,but then again I pretty much made it up on the spot. I guess that works well too. :)

-Eight men are gathered together in a remote desert. They are waiting for something. After a time the drone of a plane is heard. It approaches, and eventually a light aircraft comes into view. It circles the eight men, banks, comes down closer. A door opens in the side of the plane, a package is thrown out, and the plane flies off into the distance. The eight men run to the package and examine it. It turns out to be a human arm, neatly wrapped in surgical dressings and outer packaging. They look at it, look at one another, nod their satisfaction; then they bury the arm in the deserrt sand, and go their separate ways - as far as we know, not to meet again.

In a very exclusive bar in New York two men meet. One of them is an eminent surgeon, the other nobody in particular. The surgeon presents the other with a banker's cheque for half a million dollars. The other man examines it, expresses his satisfaction, and they part.

The best I can come up with is that the eight men waiting there had struck a deal with the surgeon.
He was to give them his arm, or something, maybe because he made them lose one or they were in a situation where everyone should have lost one and he didn't.
He, being rich, has found some poor person and offered him enough money to get out of his problem in exchange for his arm.
So the surgeon has the nobody's arm delivered to the eight men and gives money to the nobody and everyone is satisfied because they think the dela has come full circle.
They bury the arm because it's of symbolic value, but they can't really do anything with it.
Leads me to suspect the other arms are gone too and not just transplanted onto others or something

Suitepee

07-06-2008, 08:09 PM

The best I can come up with is that the eight men waiting there had struck a deal with the surgeon.
He was to give them his arm, or something, maybe because he made them lose one or they were in a situation where everyone should have lost one and he didn't.
He, being rich, has found some poor person and offered him enough money to get out of his problem in exchange for his arm.
So the surgeon has the nobody's arm delivered to the eight men and gives money to the nobody and everyone is satisfied because they think the dela has come full circle.
They bury the arm because it's of symbolic value, but they can't really do anything with it.
Leads me to suspect the other arms are gone too and not just transplanted onto others or something

Wow,that's pretty much the right answer there,except for the fact the surgeon didn't make a deal from the start. :eek: :eek: :eek:

The solution is that the surgeon and the eight men were part of the same army unit,stuck in a desert.
They all agree to donate one arm to survive; the surgeon being last to do so because he amputates the rest.
The plane arrives before the surgeon removes his arm,but he promises to honour his agreement of removing his arm to his army friends.

The surgeon however disappears and builds up a wealthy practice.
He then offers a derelict person one million to amputate his arm; half a million there & then.
The surgeon then shows the 'arm' to the other eight army men,who accept it. After this the surgeon meets the derelict person again and gives him the other half a million dollars.

Viluin

07-06-2008, 08:15 PM

Yes, the riddle makes 3 statements. But one of them is false and you must find out which.

The riddles says that if there was 10 blue-eyed persons on the island (it works for 2 or more), everyone already knew that there was at least one person with blue eyes. That's obvious.

But that doesn't mean they didn't get new information. They needed the stranger to say this for the process of killing themselves to happen. Why? What new information did they get from the stranger's statement top kick off the process?

Right above the 3 statements, it says the people didn't learn anything new from the stranger. That's supposed to be accurate information we need to solve the riddle. For that reason, statement #3 MUST be correct otherwise the riddle is flawed.

Lachrymose

07-06-2008, 08:19 PM

kehmesis

07-06-2008, 08:35 PM

Right above the 3 statements, it says the people didn't learn anything new from the stranger. That's supposed to be accurate information we need to solve the riddle. For that reason, statement #3 MUST be correct otherwise the riddle is flawed.

The 3 statements are simply a resume of the riddle. The riddle says that they lived before (otherwise they wouldn't meet a stranger), that they killed themselves after wards and that they didn't learn anything new from the stranger.

I'm unsure what you're getting at. That's the puzzle. I give you 3 statements, but I'm explaining to you why one of them has to be false otherwise there's a paradox (or in your words, it's flawed).

Yes, it is flawed. There is a paradox. Fix it!

Viluin

07-06-2008, 08:37 PM

I'm unsure what you're getting at. That's the puzzle. I give you 3 statements, but I'm explaining to you why one of them has to be false otherwise there's a paradox (or in your words, it's flawed).

Yes, it is flawed. There is a paradox. Fix it!

The story says the people did not learn anything new from the stranger because everyone, including the blue-eyed people, already knew there was at least 1 person with blue eyes. If the story is false how are we supposed to answer the question?

kehmesis

07-06-2008, 08:40 PM

The story says the people did not learn anything new from the stranger because everyone, including the blue-eyed people, already knew there was at least 1 person with blue eyes. If the story is false how are we supposed to answer the question?

Well they did know there was at least 1 person with blue eyes. To find the answer, you have to ask yourself whether they could kill themselves before the stranger came, or whether they could all survive after the stranger came, or whether they did in fact gain new information from the stranger's statement.

Viluin

07-06-2008, 08:43 PM

Well they did know there was at least 1 person with blue eyes. To find the answer, you have to ask yourself whether they could kill themselves before the stranger came, or whether they could all survive after the stranger came, or whether they did in fact gain new information from the stranger's statement.

The story literally states "So they actually didn't learn anything new from the stranger". If #3 is not true then the story lies.

Ample

07-06-2008, 09:01 PM

I know the answer to the petals around the rose game, but i didn't figure it out = /
I suck at all riddles, so i had to look it up before i wasted more than 15 minutes of my life thinking about it.
I must say it is pretty clever, I know you aren't supposed to give out any information besides "the name of the game is important" "the answer is always even or 0"... but i think its fair to say... the color of the die on that website has no significance, i was trying to make something of that but this game is traditionally played with just your average 5 die.

Suitepee

07-06-2008, 11:14 PM

lol, how are you supposed to infer all of that? :rolleyes:

You find out the rest by questioning the events in the story.
According to the book,stuff like this was/is part of FBI interrogation training.

Suitepee

07-06-2008, 11:15 PM

-Why do Chinese men eat more rice than Japanese men?
(no,the answer is not a racial slur of any kind,nor is the riddle itself)

HorrorHotel

07-06-2008, 11:36 PM

-Why do Chinese men eat more rice than Japanese men?
(no,the answer is not a racial slur of any kind,nor is the riddle itself)

There are more Chinese men than Japanese men.

kehmesis

07-07-2008, 06:07 AM

Ablu found riddle #2, congrats!

Lachrymose

07-07-2008, 06:12 AM

The story literally states "So they actually didn't learn anything new from the stranger". If #3 is not true then the story lies.

the story states all 3 of those statements, but if that's the case, it creates a paradox, therefore one of the things stated in the story (they are all stated or implied) MUST be false.

kehm, what's the answer to 2?

Satan

07-07-2008, 09:03 AM

Viluin

07-07-2008, 09:20 AM

the story states all 3 of those statements, but if that's the case, it creates a paradox, therefore one of the things stated in the story (they are all stated or implied) MUST be false.

kehm, what's the answer to 2?

No. With the way the flawed riddle is worded, the 3 statements are about the case where 10 people have blue eyes. Those 10 people did not kill themselves before the stranger showed up and they did not learn anything new from the stranger, according to the story. It does not say they killed each other after the stranger appeared so that one must be false.

Maize

07-07-2008, 09:29 AM

for #2

the second statement is false. No one started killing themselves after the stranger came because either all or a majority of the villagers had blue eyes, and any given individual could look at anyone else's eyes and figure himself safe. The stranger provided no new information because they could see for themselves that this was true, and that there was still no way to tell if they themselves had blue eyes.

Amaryl

07-07-2008, 04:44 PM

Wow,that's pretty much the right answer there,except for the fact the surgeon didn't make a deal from the start. :eek: :eek: :eek:

The solution is that the surgeon and the eight men were part of the same army unit,stuck in a desert.
They all agree to donate one arm to survive; the surgeon being last to do so because he amputates the rest.
The plane arrives before the surgeon removes his arm,but he promises to honour his agreement of removing his arm to his army friends.

The surgeon however disappears and builds up a wealthy practice.
He then offers a derelict person one million to amputate his arm; half a million there & then.
The surgeon then shows the 'arm' to the other eight army men,who accept it. After this the surgeon meets the derelict person again and gives him the other half a million dollars.

there isn't enough information in this story to relate this kind of information.

how do you know the other eight men had an arm amputated? and why would the eight men either stay in the desert, or go back to the desert to wait for the surgeon to build up a practice before donating his arm? the "solution" and the "problem" are both filled with to many holes, and it simply sounds like shooting in the dark and hope you hit the right target.

what if the 8 eight men were tribal leaders, gathering every year at a certain spot? and an arm drops down from a plane and they take it as somekind of omen to never meet up again? and that the arm infact was a transplant item designated for someone the surgeon didn't like and there for payed a crewmember of the plane to get rid of it? its just that unlikly and yes with less plot holes, from the given information.

kehmesis

07-07-2008, 04:47 PM

No. With the way the flawed riddle is worded, the 3 statements are about the case where 10 people have blue eyes. Those 10 people did not kill themselves before the stranger showed up and they did not learn anything new from the stranger, according to the story. It does not say they killed each other after the stranger appeared so that one must be false.

Yes, if you understood it correctly, it states that after the stranger came, if N people have blue eyes, they will kill themselves on day N.

So if there was 10 people with blue eyes (it was only an example), they would kill themselves on day 10.

kehmesis

07-07-2008, 04:50 PM

oh ok, i understand what you're saying about #2 now

in that case

3 they did receive new information. since they were all together when they heard the statement they got a shared starting point to count the number of days. before they couldnt talk and they all knew there was atleast 1 blue eyed person, but now theyre all in sync to kill themselves.

that would be my guess

You are very close.

However, it's not it. Being in sync isn't enough. If they all have the same reasoning and logic, they will, at one point, be in sync with each other before the stranger comes. At one point, they will all realize that there is at least 1 blue eyed person on the island, yet, they do not do anything about it.

Vanno

07-07-2008, 04:52 PM

First one is a standard in logic courses.

Indah

07-07-2008, 05:34 PM

Wow.

http://www.borrett.id.au/computing/petals-j.htm

Someone try to solve this. It's driving me nuts.

Got this one in about 2 minutes, but i cant for the life of me figure out the hats riddle. Seems impossible to me.

Add up the total of the odd dice, then subtract the number of odd dice to get your answer. 6 4 5 2 3 = 8 - 2 = 6

#1 hats riddle

So if the guy in the back sees a black hat and a white hat, he can not know what color hat he has, its either black or white. So if the guy by himself knows that by him not saying anything, he is in that predicament. So how can he know what color hat he has, if the guy can see 2 of the hats and cant see his own.

Indah

07-07-2008, 06:04 PM

Whats the 3rd riddle you had kehmesis?

stalwart

07-07-2008, 06:15 PM

i wish i'd gotten here earlier.

1st - if the guy in the middle of the two others doesn't hear an answer from behind him then he knows his is white.

2nd - i'll check it out in a minute.

Now, let's say there were 10 people with blue eyes in total. Everyone on the island already knew that at least one of them had blue eyes. So they actually didn't learn anything new from the stranger.

So that creates a paradox:

1. They didn't kill themselves before the stranger came.
2. They started killing themselves after the stranger came.
3. They didn't learn anything new from the stranger.

One of these affirmation MUST be wrong. Which one is it?

If you pick #1 or #2, you must explain why they did or did not kill themselves before/after the stranger came. If you pick #3, you must explain what new information they learned from the stranger.

i see a problem here. 3 is correct. it says so in the problem.

1 and 2 could both be wrong if the stranger came and told them WHILE they were killing themselves? after all, it would take a few days to figure out that they had blue eyes (waiting to see if the others killed themselves).

otherwise i don't see it.

Indah

07-07-2008, 06:20 PM

nice stalwart on #1,

try this one
http://www.borrett.id.au/computing/petals-j.htm

stalwart

07-07-2008, 06:54 PM

nice stalwart on #1,

try this one
http://www.borrett.id.au/computing/petals-j.htm

got it. that one wasn't bad. took around 20 or so rolls of the dice and writing down the parameters + looking at the answers. the color shit through me off for around 5-6 rolls. i figured it had to do with that...

edited out the answer.

Indah

07-07-2008, 08:52 PM

Ok, i was thinking about hat thing. Even if the guy in the middle knows, his hat is white, he cant see the guy behind him so his hat could be white or black. So i am confused again on #1

kehmesis

07-07-2008, 08:54 PM

i see a problem here. 3 is correct. it says so in the problem.

1 and 2 could both be wrong if the stranger came and told them WHILE they were killing themselves? after all, it would take a few days to figure out that they had blue eyes (waiting to see if the others killed themselves).

otherwise i don't see it.

Ok, I must have badly expressed myself because this problem keeps popping up, and I can't edit the original post.

The riddle (problem) actually says that all 3 are correct. So assuming #3 is correct is the same as assuming they are all correct, which is obviously wrong because there must be one that is false.

But let's assume that #3 is correct and #1 is wrong (let's exclude both happening at the same time...) you're not explaining to me how they could figure out what color their own eyes are before the stranger came. So as far as I'm concerned, they're not killing themselves before the stranger states the obvious.

Viluin

07-07-2008, 08:56 PM

kehmesis

07-07-2008, 09:02 PM

If the riddle is wrong about saying they did not learn anything new, then it can also be wrong about saying they'll kill each other after the stranger appears. #2 could be wrong.

Yes. It could be wrong, as expressed in the riddle, because one of them has to be wrong (exactly 2 of them are right, only 1 of them is wrong). However, I can explain to you how they would kill themselves after N days, N being the number of blue eyed people on the island. It was explained in the riddle as well, but you should figure it out for yourself to truly understand the problem.

If by miracle you can find a flaw in that logic (you won't be able to), then tell me and you will have found the answer to the riddle.

But that's not the answer to the riddle, because there's no flaw in that logic. Do it yourself, you will see.

If there is one blue-eyed person on the island, he will kill himself on the first day, seeing as no one else has blue eyes. (I REALLY hope you at least get that one)

If there is 2 blue-eyed persons on the island, they will kill themselves on the 2nd day, seeing as no one killed themselves on the first day.

If there is 3 blue-eyed persons on the island, they will kill themselves on the 3rd day, seeing as no one killed themselves on the 2nd day.

And so on for all N possibilities.

That logic isn't flawed and so that statement isn't wrong. So either they killed themselves before the stranger came or they did get new information when the stranger came, because those with blue eyes WILL kill themselves.

stalwart

07-07-2008, 09:06 PM

Ok, I must have badly expressed myself because this problem keeps popping up, and I can't edit the original post.

The riddle (problem) actually says that all 3 are correct. So assuming #3 is correct is the same as assuming they are all correct, which is obviously wrong because there must be one that is false.

But let's assume that #3 is correct and #1 is wrong (let's exclude both happening at the same time...) you're not explaining to me how they could figure out what color their own eyes are before the stranger came. So as far as I'm concerned, they're not killing themselves before the stranger states the obvious.

i mean, we're dealing with paradoxes here, so i'll say that i was correct AND wrong at the same time.

Now, let's say there were 10 people with blue eyes in total. Everyone on the island already knew that at least one of them had blue eyes. So they actually didn't learn anything new from the stranger.

they all know that at least one person had blue eyes, sure... they can see that. only problem is that nobody told them how many there were. once the stranger comes and says that there is someone with blue eyes, they can figure wait until someone kills themselves or they know that the stranger was talking about them.

go back to the situation where there were only 2 people with blue eyes... the 10 people with blue eyes is the same problem but they try to confuse it.

the problem is in the original phrasing of the problem. it presents this BEFORE the paradox:

Now, let's say there were 10 people with blue eyes in total. Everyone on the island already knew that at least one of them had blue eyes. So they actually didn't learn anything new from the stranger.

when it should be after. the way it's phrased in the original post, #1 is wrong. they wouldn't have killed themselves before because while they know the others have blue eyes, they don't have enough information to know that they also have blue eyes.

Viluin

07-07-2008, 09:07 PM

If by miracle you can find a flaw in that logic (you won't be able to), then tell me and you will have found the answer to the riddle.

Here's the flaw. If there are 10 people with blue eyes, then they're not magically going to deduce that they should kill each other after 10 days. Not only is it completely stupid that it should take 10 days for them to figure it out, but it is also highly unlikely they will all think "Wow, no one has killed themselves yet, I must be the 10th guy!" and then they all kill themselves at the same time.

Besides, get this, someone might have brown eyes and think he's the xth guy and kill himself at the exact same time the others do!

Indah

07-07-2008, 09:08 PM

explain the hat one please

kehmesis

07-07-2008, 09:09 PM

when it should be after. the way it's phrased in the original post, #1 is wrong. they wouldn't have killed themselves before because while they know the others have blue eyes, they don't have enough information to know that they also have blue eyes.

Exactly, they don't have enough information to know that they also have blue eyes. Congrats, you have figure out that #1 is RIGHT. They did not kill themselves before the stranger came.

I'm looking for the statement that is false, however.

kehmesis

07-07-2008, 09:13 PM

Here's the flaw. If there are 10 people with blue eyes, then they're not magically going to deduce that they should kill each other after 10 days. Not only is it completely stupid that it should take 10 days for them to figure it out, but it is also highly unlikely they will all think "Wow, no one has killed themselves yet, I must be the 10th guy!" and then they all kill themselves at the same time.

Besides, get this, someone might have brown eyes and think he's the xth guy and kill himself at the exact same time the others do!

They're not magically deducing it, they are deducing it because each of those 10 people expected the other 9 blue eyed to kill themselves on the 9th day. But they didn't, so each of them deduces that they have blue eyes as well.

There's nothing magical to it. It's just logic. It's also not stupid that it should take 10 days, it's the only way to find out if they have blue eyes or not. Once they kill themselves, the rest of the island now deduces that they do NOT have blue eyes.

While it is unlikely that they would try and deduce the color of their own eyes, they will do it because it is stated in the riddle. And NOT as one of the 3 possible statements that could be false. So if they CAN deduce it, they WILL.

EDIT: Someone with brown eyes will never kill himself because he sees 1 more people with blue eyes than those who do have blue eyes. The brown eyed guy sees 10 people with blue eyes. All the blue-eyed people see 9 people with blue eyes. That is why the brown eyed guy will never think he is the 10th one. He might think he is the 11th, but since they will all be dead on the 10th day, he'll know he doesn't have blue eyes.

kehmesis

07-07-2008, 09:14 PM

explain the hat one please

It has been spoiled plenty already, but here it is one more time:

The guy in the middle on the right side of the wall figures his hat is a different color than the guy in front of him, because the guy behind him can't find the color of his own hat.

Viluin

07-07-2008, 09:18 PM

They're not magically deducing it, they are deducing it because each of those 10 people expected the other 9 blue eyed to kill themselves on the 9th day.

Why would it take 9 days? Someone might deduce the whole thing in 10 minutes. But then he would be unsure if the others also deduced it, so he would wait to see if the others kill themselves first. The same probably applies to the others as well, so no one ends up killing himself.

Or, 9 people deduce it and kill themselves until there is only 1 person left. He would not kill himself because he has no reason to believe he has blue eyes.

stalwart

07-07-2008, 09:18 PM

hrm. i'll change my answer, i guess. i'm kind of lost and getting the puzzles mixed up.

#3 is false. they did learn anything new from the stranger. they learned his perspective. once they had that, they had enough information to kill themselves (and i'm sure they were appreciative).

stalwart

07-07-2008, 09:19 PM

Why would it take 9 days? Someone might deduce the whole thing in 10 minutes. But then he would be unsure if the others also deduced it, so he would wait to see if the others kill themselves first. The same probably applies to the others as well, so no one ends up killing himself.

Or, 8 people deduce it until there are only 2 people left. Those 2 people will each think the other would be the last remaining blue-eyed person because they have nothing that indicates otherwise. They wouldn't kill themselves.

vil brings up an interesting point. why doesn't the entire colony kill themselves after seeing that nobody else killed themselves after the first day?

they'd be like "nobody else did, it must be me."

Indah

07-07-2008, 09:24 PM

It has been spoiled plenty already, but here it is one more time:

The guy in the middle on the right side of the wall figures his hat is a different color than the guy in front of him, because the guy behind him can't find the color of his own hat.

But how does the 2nd guy know the last guys hat is black, it could be white just as easily.

kehmesis

07-07-2008, 09:25 PM

vil brings up an interesting point. why doesn't the entire colony kill themselves after seeing that nobody else killed themselves after the first day?

they'd be like "nobody else did, it must be me."

As I explained, the blue eyed people see one person less with blue eyes than those who do not have blue eyes. If you don't have blue eyes, you'd need to wait an extra day to figure out that you do. So the blue-eyed people will always kill themselves before the non blue-eyed people.

---

Your previous answer is not very clear. It's not totally false, but seeing his perspective isn't exactly new information, because his perspective is that there is at least 1 person with blue eyes, which they already know.

But you're getting closer.

kehmesis

07-07-2008, 09:28 PM

But how does the 2nd guy know the last guys hat is black, it could be white just as easily.

Guy

#1 (wall) #2 - #3 - #4

We're in #3's head.

Guy #3 finds the color of his own hat, because #4 can't figure out the color of his own, which means that guy #2 must have a different hat than his own (otherwise it would be child's play for guy #4 to find the color of his own hat).

Viluin

07-07-2008, 09:28 PM

As I explained, the blue eyed people see one person less with blue eyes than those who do not have blue eyes. If you don't have blue eyes, you'd need to wait an extra day to figure out that you do. So the blue-eyed people will always kill themselves before the non blue-eyed people.

Why do they wait for several days? The entire thing could happen in a few minutes. They could all kill themselves after 10 minutes. Or they could not. That alone means no one will kill themselves because it's impossible to know for sure that you are one of the blue-eyed people. The N days for N amount of blue-eyed people thing is just stupid, it won't happen like that.

stalwart

07-07-2008, 09:33 PM

lol @ viluin's "it just wouldn't happen like that." it's a riddle, of course it wouldn't.

but the point is the same. you said "they would just have to wait an extra day" the end sum of the whole timeline is factorial in proportion to the people in the colony, sounds like.

100 people. 100 factorial or something thereof in regards to whatever unit you want to say this takes... 1 day?

then we're getting into the realm of, "are these people's lives long enough to actually kill themselves?"

it's factorial because they all need to wait a unit of time before X person kills themselves. then Y. then Z. if Z does, then they need to wait to see if X kills himself, because X might have just waiting to see if Y or Z did. Then if Y doesn't kill himself the next day, X can finally kill himself.

you can see how this is factorial?

Viluin

07-07-2008, 09:36 PM

Okay, let's put it like this. Let's say there are 2 people with blue eyes.

Person #1 might deduce that person #2 hasn't killed himself because person #1 has blue eyes as well. So person #1 kills himself. Person 2 would then assume person #1 killed himself because person #1 saw no one with blue eyes, automatically meaning person #1 had blue eyes.

There. If there were 2 people with blue eyes, only one of them would kill himself.. The person who deduces the entire thing first.

Indah

07-07-2008, 09:37 PM

Guy

#1 (wall) #2 - #3 - #4

We're in #3's head.

Guy #3 finds the color of his own hat, because #4 can't figure out the color of his own, which means that guy #2 must have a different hat than his own (otherwise it would be child's play for guy #4 to find the color of his own hat).

Doh, i thought they had to guess #1's hat. Was making the riddle impossible.

Indah

07-07-2008, 09:39 PM

Viluin

07-07-2008, 09:41 PM

If there were 3 people and person #1 killed himself after deducing it all, person #2 and #3 would both assume the other was the remaining blue-eyed person of a duo that thought person #1 killed himself because he saw no one else with blue eyes. This can go on and on, right up to 10 people. In every situation, only 1 person would kill himself. #2 must be wrong because they did not kill "themselves". One person killed himself.

Riddle solved imo.

The riddle states they would do it at the same time. Now you are arguing points that are assumed when saying its a riddle.

The riddle also states they did not learn anything new from the stranger. The riddle must be wrong about something, it might as well be the killing.

kehmesis

07-07-2008, 09:45 PM

The religion says: when you learn the color of your eyes, you must kill yourself before the next day.

Hence why it takes N days to figure it out, not a couple of minutes. You don't kill yourself instantly, though you may. But not until the next day will you know how many killed themselves, if any.

Viluin

07-07-2008, 09:46 PM

When you learn the color of your eyes, you must kill yourself before the next day.

This changes nothing. The first person who deduces the entire thing kills himself. The rest will not kill themselves because of the reason I provided in my last 2 posts.

Indah

07-07-2008, 09:49 PM

This changes nothing. The first person who deduces the entire thing kills himself. The rest will not kill themselves because of the reason I provided in my last 2 posts.

according to that statement, then the first guy to figure it out, would kill himself, but there are still 9 other blue eyed people, and 8 of the 9 would kill themselves till there is just a retard with blue eyes thinking he wins.

kehmesis

07-07-2008, 09:53 PM

Viluin, here's the new riddle, just for you (forget the other one):

I'll skip the religion story, but remember that if one knows the color of his own eyes, he must kill himself before the next day. We're right before the stranger arrives.

Whatever is in the spoiler text is TRUE. If you disagree, you are misunderstanding. Keep working on it.

1. Is it possible that any of them could find out the color of their own eyes and kill themselves?

When you have the answer, continue.

No, it's impossible.

The stranger says: There is at least one person with blue eyes. Leaves.

2. What happens if there is only 1 person with blue eyes?

When you have the answer, continue.

He'll see that no one else has blue eyes, and he'll be dead by next morning

3. What happens if there is 2 persons with blue eyes?

When you have the answer, continue.

One the first day, no one kills himself because both persons with blue eyes see at least one person with blue eyes, so they cannot deduce they have blue eyes themselves. On the 2nd day, they will both see that the only person with blue eyes on the island didn't kill himself, so they will both realize that they have blue eyes themselves and kill themselves on that day.

4. What happens if there is N persons with blue eyes?

When you have the answer, continue.

They will all kill themselves on day N.

5. Since they already knew there was at least 1 person with blue eyes before the stranger told them, what new information did they get from the stranger?

When you have the answer, post it.

Viluin

07-07-2008, 09:54 PM

according to that statement, then the first guy to figure it out, would kill himself, but there are still 9 other blue eyed people, and 8 of the 9 would kill themselves till there is just a retard with blue eyes thinking he wins.

No. Take a look at my example about 3 people. Only one of them will kill himself in that example. The same goes for 10 people.

The whole "before the next day" thing doesn't change anything. if there was only one person with blue eyes, he would figure it out instantly and kill himself. In a scenario with 2 people, person #1 might deduce that, since person #2 has not killed himself within a very short amount of time, person #1 must also have blue eyes. So person #1 kills himself on the spot. Person #2 will then be unsure whether or not person #1 saw another person with blue eyes or if person #1 knew he was the only one. Person #2 would therefore not kill himself.

3. What happens if there is 2 persons with blue eyes?

When you have the answer, continue.

One the first day, no one kills himself because both persons with blue eyes see at least one person with blue eyes, so they cannot deduce they have blue eyes themselves. On the 2nd day, they will both see that the only person with blue eyes on the island didn't kill himself, so they will both realize that they have blue eyes themselves and kill themselves on that day.

That's not how it would happen.

kehmesis

07-07-2008, 09:54 PM

This changes nothing. The first person who deduces the entire thing kills himself. The rest will not kill themselves because of the reason I provided in my last 2 posts.

The first person? They will all deduce it. All of them will deduce it as soon as they see no one killed themselves the day before. So they will all kill themselves.

kehmesis

07-07-2008, 09:57 PM

In a scenario with 2 people, person #1 might deduce that, since person #2 has not killed himself within a very short amount of time, person #1 must also have blue eyes. So person #1 kills himself on the spot. Person #2 will then be unsure whether or not person #1 saw another person with blue eyes or if person #1 knew he was the only one. Person #2 would therefore not kill himself.

#1 could not possibly have been the only one otherwise he would have died on the first day. But he did not kill himself on the first day because he saw someone else with blue eyes.

When they wake up the next morning, both of them will know they have blue eyes because the blue eyed person isn't dead yet.

---

You and I are the only ones with blue eyes. The first day, I'll see you and think "I'm safe, viluin is the only one with blue eyes. You'll see me and think "I'm safe, kehm is the only one with blue eyes. So we won't kill ourselves on that day.

The next morning, I wake up, and I see that you are still alive. I'll think: "fuck, viluin didn't kill himself, so I must also have blue eyes. You'll think: "fuck, kehm didn't kill himself, so I must also have blue eyes."

We both kill ourselves that day. It doesn't matter when. Sometime during that day, because we must. The next morning (3rd day), everyone else wakes up and think: "Nice, Kehm and Viluin killed themselves, so there were only 2 with blue eyes, I'm safe.".

Viluin

07-07-2008, 09:57 PM

The first person? They will all deduce it. All of them will deduce it as soon as they see no one killed themselves the day before. So they will all kill themselves.

No. Even if person #1 kills himself on day 2, person #2 is still not sure whether or not he has blue eyes. Maybe person #1 was just slow in figuring out he was the only one. "Learning the color of your eyes" implies 100% certainty, which is not present so person #2 would not kill himself.

In fact, there is never 100% certainty. The others might just be too stupid to deduce the situation and that might be why they aren't killing themselves! Therefore, no one will kill himself.

kehmesis

07-07-2008, 10:05 PM

No. Even if person #1 kills himself on day 2, person #2 is still not sure whether or not he has blue eyes. Maybe person #1 was just slow in figuring out he was the only one. "Learning the color of your eyes" implies 100% certainty, which is not present so person #2 would not kill himself.

In fact, there is never 100% certainty. The others might just be too stupid to deduce the situation and that might be why they aren't killing themselves! Therefore, no one will kill himself.

No, everyone on the island have the same reasoning and logic. If it is possible to find it, they will find it. And it is logically possible. In other words, you're not on the island. Better?

PrimalSign

07-07-2008, 10:10 PM

The deductive reasoning chain:
(assumes everybody in the village knows everybody else, their eye color, and they all think the same)

1. If one person is a blue eyes he will see nobody else with blue eyes, and kill himself.

2. If two people have blue eyes they will assume the other blue eye will commit suicide on the first day. When the first person does not commit suicide, they will each realize the other person sees a blue eyes, and since they know everybody else doesn't have blue eyes, they must be the second blue eye.

3. The three will expect the scenario in number 2, and when it does not occur on the 2nd day, each of them will realize they are also a blue eye, and kill themselves.

and so on and so forth...

Correct me if I'm wrong OP. Viluin, it helps if you realize the villagers are not real people but simply a part of a deductive reasoning exercise.

Viluin

07-07-2008, 10:12 PM

No, everyone on the island have the same reasoning and logic. If it is possible to find it, they will find it. And it is logically possible. In other words, you're not on the island. Better?

They may have the same reasoning and logic, but do they know it? You can't know what the others are thinking unless they tell you. And they can't tell you what they're thinking, because they're thinking about your eye color.

Indah

07-07-2008, 10:13 PM

but blue eyes person #3 was my brother man!

F8alist

07-07-2008, 11:10 PM

#2

With only 1 blue-eyed person on the island, the revelation that there is at least one person with blue eyes is new information for that person. That much is obvious to everyone.

With 2 blue-eyed people on the island, everyone already knows there is at least one blue-eyed person on the island. What everyone didn't already know was that everyone knew that. When the stranger states that there is at least one blue-eyed person on the island, then everyone knows that everyone knows.

With 3 blue-eyed people on the island, everyone already knows that everyone already knows there is at least one blue-eyed person on the island (if Larry, Moe and Curley all have blue eyes, then Larry knows that Moe can see Curley and that Curley can see Moe)

The new information they gain is that everyone knows that everyone knows that everyone knows there is at least one blue-eyed person on the island. (if Larry, Moe and Curley all have blue eyes, Larry knows that Moe can see Curley, but prior to the stranger's statement, Larry wouldn't have known that Moe knew that Curley knew there was at least one person with blue eyes.)

etc...

Did that make any sense to anyone?

Ftang

07-07-2008, 11:17 PM

#2

Did that make any sense to anyone?

yup..nailed it i think.

kehmesis

07-08-2008, 02:52 AM

kehmesis

07-08-2008, 02:53 AM

Tomaj

07-08-2008, 04:08 AM

#2. The fucked up religion

A community lives on an island, far from civilization. They have a very weird religion: if one knows the color of his own eyes, he must commit suicide before the next day. And while you can see everyone's eye color, you must not tell anyone what color their eyes are. However, they are all very logical and have the same reasoning, so if they can figure out the color of their own eyes, they will. There are no mirrors and they cannot see the reflection of their eyes in water or any other bullshit.

One day, a stranger comes to the island and says: "At least one of you has blue eyes." He then leaves.

Now, what happens if there is only one person on the island with blue eyes? He will see that no one has blue eyes, and logically deduce that he must be the one to have blue eyes. So he will kill himself before the next day.

What if two people have blue eyes? The first day, they will both think that the other will kill himself before the next day. But the 2nd day, seeing that the blue eyed person didn't kill himself, he will logically deduce that they also have blue eyes and both will kill themselves before the next day.

What if three people have blue eyes? The 3rd day, seeing that the two other people with blue eyes didn't kill themselves, he will logically deduce that they also must have blue eyes, so they will all kill themselves before the next day.

And so on. (If you don't get this, get a pen and paper and work on it! It is vital that you understand and agree this is what would happen.)

Now, let's say there were 10 people with blue eyes in total. Everyone on the island already knew that at least one of them had blue eyes. So they actually didn't learn anything new from the stranger.

So that creates a paradox:

1. They didn't kill themselves before the stranger came.
2. They started killing themselves after the stranger came.
3. They didn't learn anything new from the stranger.

One of these affirmation MUST be wrong. Which one is it?

If you pick #1 or #2, you must explain why they did or did not kill themselves before/after the stranger came. If you pick #3, you must explain what new information they learned from the stranger.

this cant be true in any way becase no one knows if they have blue eyes, so it dosnt matter howmany people they see with blue eyes they will just wonder why there not dead. if you have only 1 person with brown eyes and 49 with blue and none of them knows what there eye collor is no one will die un less they start telling who has blue eyes. butin the riddle they can not. thus with out being told they wont know they have the blue eyes and will just see 48 other people with blue eyes and 1 with brown. however it could work if as the stranger leaves and says only one person has blue eys they look at the one person they would deduce they have the blue eyes as they would know why they where looked at. this riddle is flawed as there are to many holes in it. most are wich is why they are hard you have to ather obscure clues to guess at the info you dont know and thus if 50 people guess at the answer chances are you will get 50 vairied results.

HorrorHotel

07-08-2008, 04:21 AM

Yup, congrats! 2nd one to find it.

Are you shitting me? That doesn't make any fucking sense. At all.

No, really.

MCBach

07-08-2008, 04:52 AM

The island visitor was a lair. In fact, the OP is the lying island visitor. Burn him.

HorrorHotel

07-08-2008, 04:58 AM

The island visitor was a lair. In fact, the OP is the lying island visitor. Burn him.

All of the island dwellers are blind. HAH!

Fledrel

07-08-2008, 05:55 AM

When you have the answer, post it.

They all had blue eyes. The new information was that the color of the eyes that they see is blue.

Or the strager mearly confirmed that One person has blue eyes. Until this point there was no logical certanity to the statement

kehmesis

07-08-2008, 06:11 AM

They all had blue eyes. The new information was that the color of the eyes that they see is blue.

Or the strager mearly confirmed that One person has blue eyes. Until this point there was no logical certanity to the statement

Well, they do know their colors, so yes, they did know there was at least 1 person with blue eyes before the stranger came.

He did confirm it. But that doesn't answer the question. They all were CERTAIN there was at least one person with blue eyes, because they all saw at least one person with blue eyes. That's certainty, right there.

HorrorHotel

07-08-2008, 06:17 AM

Well, they do know their colors, so yes, they did know there was at least 1 person with blue eyes before the stranger came.

He did confirm it. But that doesn't answer the question. They all were CERTAIN there was at least one person with blue eyes, because they all saw at least one person with blue eyes. That's certainty, right there.

I had sensed some sort of cocaine usage from this riddle from the get-go, but this confirms it.

Seeing is not believing. To have to assume that to "solve" a logic puzzle is ridiculous.

kehmesis

07-08-2008, 06:17 AM

this cant be true in any way becase no one knows if they have blue eyes, so it dosnt matter howmany people they see with blue eyes they will just wonder why there not dead. if you have only 1 person with brown eyes and 49 with blue and none of them knows what there eye collor is no one will die un less they start telling who has blue eyes. butin the riddle they can not. thus with out being told they wont know they have the blue eyes and will just see 48 other people with blue eyes and 1 with brown. however it could work if as the stranger leaves and says only one person has blue eys they look at the one person they would deduce they have the blue eyes as they would know why they where looked at. this riddle is flawed as there are to many holes in it. most are wich is why they are hard you have to ather obscure clues to guess at the info you dont know and thus if 50 people guess at the answer chances are you will get 50 vairied results.

Try reading the 3rd post on the 9th page, I think I have explained the riddle more clearly.

The riddle isn't flawed, it's from a solid source, it's a friend with a math PHD.

My explanation, however, could probably be better. But I think it's fine. Two people found the answer so far, so it must be at least understandable.

You're just not getting it.

HorrorHotel

07-08-2008, 06:26 AM

Try reading the 3rd post on the 9th page, I think I have explained the riddle more clearly.

The riddle isn't flawed, it's from a solid source, it's a friend with a math PHD.

My explanation, however, could probably be better. But I think it's fine. Two people found the answer so far, so it must be at least understandable.

You're just not getting it.

This thread only has 2 pages. You're shitting me.

Considering you don't have much of a way of confirming that this supposed friend of yours did indeed come up with this supposed riddle and does, in fact, have a Ph.D, there is no choice but to look at the riddle as it is presented on its own merit. And it's clearly lacking. Not just lacking. It's an insult.

Paralda

07-08-2008, 06:52 AM

exactly, that's why, in the case of 3 blue eyed ppl, you'll realize that the other 2 haven't killed themselves yet. so you'll know that there must be a 3rd person w/ blue eyes (there can't be a 4th b/c you know that there must be either 2 or 3 with blue eyes, 3 if you yourself have blue eyes). that's why it's important to note that all the people have the same exact reasoning process.

Yeah, but then everyone's logic would change. For instance, if there were really 3 people with blue eyes, all three of them would think there were two, and then when they hadn't killed themselves, would all think that they're the third, BUT, everyone would see that the three with blue eyes didn't kill themselves and assume that they might be the fourth. And so on and so fourth. This would go on forever, because no one could ever be absolutely certain from logical analysis.

So, number 2 is wrong.

Fledrel

07-08-2008, 07:09 AM

The riddle isnt flawed. The logic is.
Assume 1 is correct. No islanders killed themselves before the vistor came Therefore meaning that only 1 person has blue eyes.
Which leads into 2 being correct as well Since there was only 1 person with blue eyes then they would have killed themselves after the visitor.
So 3 must be incorrect. Yet the riddle states that he priovided no new info so 3 Must be correct.

So 1 or 2 must be incorrect. Yet they both say that 3 must be incorrect. They could have been killing themselves the entire time and then the stranger appeared yet that would mean both 1 and 2 are incorrect. 2 would be false becasue they hadn't started killing after he came, yet 1 would be false as well because they had been killing each other the entire time.

#3 is incorrect if there was only 1 blue eyed person. the riddle never said they knew only 1 of them had blue eyes. If there were more that 1 blue eyes then all three are incorrect and also correct depending on the timeing. Perfect logic is a tricky thing. How do you guage perfect logic without perfect logic?

The blue eyes all kill themselves on day N+1 as described countless times in this thread.
and the brown eyes will all die on day N+2.
No matter how you do the math they will all kill themselves no matter the eye color. Once they see all the blue eyes gone they will all know they have brown eyes.

Edit: just realized this riddle isn't the way i remembered it forget the brown eyes stuff >.>

Got this one in about 2 minutes...
Add up the total of the odd dice, then subtract the number of odd dice to get your answer. 6 4 5 2 3 = 8 - 2 = 6

Thats one way to do the riddle but thats not the intended way. Its petals AROUND the rose. the rose being the center pip. count the pips in the corners around the center pip. If the die has no center pip it doesnt count. so (6=0 4=0 5=4 2=0 3=2) = 6

kehmesis

07-08-2008, 07:31 AM

The riddle isnt flawed.

Nope, your logic is flawed, no one with brown eyes will kill themselves. The wrong assumptions in this thread come from people not understanding the riddle because they either simply can't understand it or they won't try to understand it.

It's funny how many people blame it on a flawed riddle, flawed logic and so on, when what is flawed is their logical sense. This is not an easy riddle, so it's normal to not "get" it.

I'm sure those who do enjoyed it. Especially the 2 who found the answer.

I got harder ones, much, much harder ones. But they require more mathematical knowledge.

This one only requires simple addition by 1, so I shared it.

kehmesis

07-08-2008, 07:34 AM

This thread only has 2 pages. You're shitting me.

Considering you don't have much of a way of confirming that this supposed friend of yours did indeed come up with this supposed riddle and does, in fact, have a Ph.D, there is no choice but to look at the riddle as it is presented on its own merit. And it's clearly lacking. Not just lacking. It's an insult.

Well, we have different settings I guess. So I dunno, there are no post numbers. It's one of the latest post I did with LOTS of spoilers.

Fledrel

07-08-2008, 07:39 AM

Nope, your logic is flawed, no one with brown eyes will kill themselves. The wrong assumptions in this thread come from people not understanding the riddle because they either simply can't understand it or they won't try to understand it.
....
This one only requires simple addition by 1, so I shared it.

The original riddle states there are only 2 colored eyes. so yes once all the blues die the browns will as well. its simple deduction.

as for the simple addition that does not explain which statement is false. As i edited all three are false and all three are true depending on when the traveler appears.

Fledrel

07-08-2008, 08:01 AM

With only 1 blue-eyed person on the island, the revelation that there is at least one person with blue eyes is new information for that person. That much is obvious to everyone.

With 2 blue-eyed people on the island, everyone already knows there is at least one blue-eyed person on the island. What everyone didn't already know was that everyone knew that. When the stranger states that there is at least one blue-eyed person on the island, then everyone knows that everyone knows.

With 3 blue-eyed people on the island, everyone already knows that everyone already knows there is at least one blue-eyed person on the island (if Larry, Moe and Curley all have blue eyes, then Larry knows that Moe can see Curley and that Curley can see Moe)

The new information they gain is that everyone knows that everyone knows that everyone knows there is at least one blue-eyed person on the island. (if Larry, Moe and Curley all have blue eyes, Larry knows that Moe can see Curley, but prior to the stranger's statement, Larry wouldn't have known that Moe knew that Curley knew there was at least one person with blue eyes.)

etc...

Did that make any sense to anyone?

This is flawed, after the third person with blue eyes no new info is offered.

If only 1 person blue eyes then yes new info prvided.
If only 2 person blue eyes then yes new info because the second person only sees 1 blue eyed person, for all he knows he could be blue eyed as well(and is).
But with three or more blue eyes then the logic interfears. If you see two people with blue eyes then you know that every person on the island sees one person with blue eyes and they know that everyone can see at least one person with blue eyes. So No new info is provided.

remember the riddle, if there is a way for them to know it logicly they will. They Can know that everyoine else knows there is at least one blue eyed person when there are at least total of 3 blue eyed people.

Viluin

07-08-2008, 01:32 PM

Nope, your logic is flawed, no one with brown eyes will kill themselves. The wrong assumptions in this thread come from people not understanding the riddle because they either simply can't understand it or they won't try to understand it.

It's funny how many people blame it on a flawed riddle, flawed logic and so on, when what is flawed is their logical sense. This is not an easy riddle, so it's normal to not "get" it.

I'm sure those who do enjoyed it. Especially the 2 who found the answer.

I got harder ones, much, much harder ones. But they require more mathematical knowledge.

This one only requires simple addition by 1, so I shared it.

I understand the riddle. Following your logic I too can find the answer. The problem is that the riddle is complete BS and not quite logical.

HorrorHotel

07-08-2008, 03:34 PM

The fact that the stranger announces that there is at least one blue eyed person is hardly enough to deduce that everyone knows that, and if we're going to be splitting hairs like that, isn't necessary.

Is he lying? Or maybe I didn't hear him. Or I didn't pay attention. All valid thoughts for someone to think that another doesn't know if they already thought that they didn't.

What's more, though, is that it wouldn't be necessary for a stranger to announce that for everyone to know that everyone else knows based on the information in the riddle (they're smart, capable of using logic, can see each other, etc.). It's BS.

Oh, and there is only one true page number.

kehmesis

07-08-2008, 04:08 PM

This is flawed, after the third person with blue eyes no new info is offered.

If only 1 person blue eyes then yes new info prvided.
If only 2 person blue eyes then yes new info because the second person only sees 1 blue eyed person, for all he knows he could be blue eyed as well(and is).
But with three or more blue eyes then the logic interfears. If you see two people with blue eyes then you know that every person on the island sees one person with blue eyes and they know that everyone can see at least one person with blue eyes. So No new info is provided.

remember the riddle, if there is a way for them to know it logicly they will. They Can know that everyoine else knows there is at least one blue eyed person when there are at least total of 3 blue eyed people.

You just have to go on if there is more than 3. Everyone knows that everyone knows that everyone knows, etc.

He gave examples for 1, 2 and 3 people. It's the same for any number of people, you just have to add a "everyone knows that".

Fledrel

07-08-2008, 04:11 PM

I feel sooo dumb, just came to a realization, #1 and #2 both inply a timetable, before and after the traveler arrives. Yet the riddle offers no time table as to when the visitor arrives. So we are all flawed from the beginning. Its like trying to solve a simple repeating number puzzle. 2...?...?...9
With out one of the ...?... we have several possibilities.

Logic is only perfect when all the variables are known. Since they don't know their own eye color then their logic is flawed and since we don't know the time frame of the visitor our logic is flawed.

It's impossible to reach a logicly sound solution without all the info. This is the only answer that can not be undone with logic. All the other answers are flawed.

Fledrel

07-08-2008, 04:12 PM

You just have to go on if there is more than 3. Everyone knows that everyone knows that everyone knows, etc.

He gave examples for 1, 2 and 3 people. It's the same for any number of people, you just have to add a "everyone knows that".

You don't go on at all everyone knows that there is at least one person with blue eyes after there are 3 blue eyed people. Therefore the traveler offers no new info.

kehmesis

07-08-2008, 04:13 PM

The original riddle states there are only 2 colored eyes. so yes once all the blues die the browns will as well. its simple deduction.

Really now? I don't know why you think there was only 2 possible eye colors.

kehmesis

07-08-2008, 04:15 PM

You don't go on at all everyone knows that there is at least one person with blue eyes after there are 3 blue eyed people. Therefore the traveler offers no new info.

See, that's flawed logic. Don't blame the riddle.

They do not learn from the stranger that there is at least one person with blue eyes. That much is sure. (And it's for all cases where N > 2, not 3). But they do get new information.

Fledrel

07-08-2008, 04:29 PM

Really now? I don't know why you think there was only 2 possible eye colors.

I don't get where you got that basterdized version of this riddle.

How is it flawed?!? i have clearly stated how yours is now do the same for mine!

They do not learn from the stranger that there is at least one person with blue eyes. That much is sure. (And it's for all cases where N > 2, not 3). But they do get new information.

No if two blue eyed people each of them will see a blue eyed person but for all their logic they will not know their own. They will think the other person is the only blue eyed and that they think they are brown.

Also not blaming the riddle just saying there is not enough info for your statements to be proven or disproven.

kehmesis

07-08-2008, 04:45 PM

No if two blue eyed people each of them will see a blue eyed person but for all their logic they will not know their own. They will think the other person is the only blue eyed and that they think they are brown.

Exactly right. That will be on the day the stranger arrives.

The next day, however, they will both see that the only (or so they thought) person with blue eyes didn't kill himself, which he should have done had he been the only one. They will make a simple deduction: "FUCK! I have blue eyes, too." This is fuckin' simple, actually, and it's not the hard part. If you can't get that, just drop it, the riddle's not for you.

I have explained this so many times and most realized I am right. You might, too, and then you'll go "ooooh, I feel dumb." like the others.

kehmesis

07-08-2008, 04:50 PM

Is he lying? Or maybe I didn't hear him. Or I didn't pay attention.

That wouldn't make a very good riddle indeed, now would it. However, I clearly stated that if they could find out what their eye color is, they would.

There's no bullshit like the stranger is lying, or deaf people or people not caring.

They all hear him, there are no retards, everybody cares...

If that's how you want to see it, that's cool. You can make up all the excuses in the world to not try and find or understand the answer to the riddle. But quit this thread, it's not for you.

kehmesis

07-08-2008, 04:51 PM

I understand the riddle. Following your logic I too can find the answer. The problem is that the riddle is complete BS and not quite logical.

Of course it's not. There are no such religions and anyone in such a religion would not try to logically deduce the color of their own eyes. But it's a logical exercise, not a reality check. Get over it.

Fledrel

07-08-2008, 04:53 PM

yes i know that. Im saying what you said was correct isnt. The taveler has to have offered up info. Or else if there was only 1 blue eyed person he would never know until the traveler told him. This is like a math equation, It must work in all situations or it isnt correct. You say the traveler doesnt give any new info so If there is only 1 person he shold kill himself without the traveler, but he doesn't. Because the riddle never said they knew there was at least one blue eyed person. We don't get that info until the traveler shows up.

I understand the N+1 thing i got that before i even finish reading the riddle. What your doing is assuming they all know there is at least one person with blue eyes. You can't do that. Your misreading/understanding the riddle

Fledrel

07-08-2008, 05:05 PM

this is why there are brown eyed people.

http://xkcd.com/blue_eyes.html
http://everything2.com/index.pl?node_id=1181120(blue and green here)
http://www.subzeroblue.com/archives/2007/09/blue_eyes_riddle.html
http://nz.answers.yahoo.com/question/index?qid=20080314162049AAcvrRS
http://apuzzleaday.org/puzzle/puzzle.php?ID=75.html

Just a few i found quickly all of these say 2 different color eyes and none of them have your flawed #1#2#3 choices.

Besides in their religion they have to kill themselves if they discover their eye color, Like I said if all one color leaves then the other group knows their own color. But even if we follow your riddle, you still don't have enough info to determine the answer. It all depends on when the traveler appears.

HorrorHotel

07-08-2008, 05:54 PM

That wouldn't make a very good riddle indeed, now would it. However, I clearly stated that if they could find out what their eye color is, they would.

There's no bullshit like the stranger is lying, or deaf people or people not caring.

They all hear him, there are no retards, everybody cares...

If that's how you want to see it, that's cool. You can make up all the excuses in the world to not try and find or understand the answer to the riddle. But quit this thread, it's not for you.

No, logic is not for you. You see, one can't be logical without knowing these simple details. If we're meant to assume that the people of your cult know this, why can we not also assume that they know they are exactly like them in regards to their capacity for critical thought?

kehmesis

07-08-2008, 09:44 PM

this is why there are brown eyed people.

http://xkcd.com/blue_eyes.html
http://everything2.com/index.pl?node_id=1181120(blue (http://everything2.com/index.pl?node_id=1181120%28blue) and green here)
http://www.subzeroblue.com/archives/2007/09/blue_eyes_riddle.html
http://nz.answers.yahoo.com/question/index?qid=20080314162049AAcvrRS
http://apuzzleaday.org/puzzle/puzzle.php?ID=75.html

Just a few i found quickly all of these say 2 different color eyes and none of them have your flawed #1#2#3 choices.

Besides in their religion they have to kill themselves if they discover their eye color, Like I said if all one color leaves then the other group knows their own color. But even if we follow your riddle, you still don't have enough info to determine the answer. It all depends on when the traveler appears.

I just picked one and read it, and this is usually only the first part of the riddle.

kehmesis

07-08-2008, 09:47 PM

yes i know that. Im saying what you said was correct isnt. The taveler has to have offered up info.

But the example was for more than 1 people (I picked 10, but it could be any other).

But even for more than 1, the community learned something new. So yes, he did offer up info. That's actually the answer. But if you can't tell me what it is they learned, you are just guessing.

PrimalSign

07-08-2008, 10:47 PM

The villagers learned there was a stranger who came to their village and told them at least 1 person has blue eyes. #3 is proven false.

Riddle solved :)

Fledrel

07-08-2008, 10:48 PM

But the example was for more than 1 people (I picked 10, but it could be any other).

But even for more than 1, the community learned something new. So yes, he did offer up info. That's actually the answer. But if you can't tell me what it is they learned, you are just guessing.

In you OP you said that he did NOT offer any new info.

If they did not know that at least one of them had blue eyes then no one would have been able to kill themselves.
Example If one person had blues eyes and he could see no one else had blue eyes then he could not kill himself with logic because he might have brown eyes and no one had blue. Same with two blue eyed people They would see that the other person did not kill themselves so either he also has blue eyes or he has brown. Same all the way up, until the traveler says "At least one of you has blue eyes." there was no logical way to find out.

You said he offered no new info and said that our logic was flawed and that we shouldn't blame the riddle now your saying you lied in your OP?