Riddle me this

[Dark Jaguar]

Here's a thread for riddles, I guess, because maybe this game might last a while.

So I'll start things off with a classic. I'll just quote it.

A group of people with assorted eye colors live on an island. They are all perfect logicians -- if a conclusion can be logically deduced, they will do it instantly. No one knows the color of their eyes. Every night at midnight, a ferry stops at the island. If anyone has figured out the color of their own eyes, they [must] leave the island that midnight. Everyone can see everyone else at all times and keeps a count of the number of people they see with each eye color (excluding themselves), but they cannot otherwise communicate. Everyone on the island knows all the rules in this paragraph.

On this island there are 100 blue-eyed people, 100 brown-eyed people, and the Guru (she happens to have green eyes). So any given blue-eyed person can see 100 people with brown eyes and 99 people with blue eyes (and one with green), but that does not tell him his own eye color; as far as he knows the totlas could be 101 brown and 99 blue. Or 100 brown, 99 blue, and he could have red eyes.

The Guru is allowed to speak once (let's say at noon), on one day in all their endless years on the island. Standing before the islanders, she says the following:

"I can see someone who has blue eyes."

Who leaves the island, and on what night?


There are no mirrors or reflecting surfaces, nothing dumb, It is not a trick question, and the answer is logical. It doesn't depend on tricky wording or anyone lying or guessing, and it doesn't involve people doing something silly like creating a sign language or doing genetics. The Guru is not making eye contact with anyone in particular; she's simply saying "I count at least one blue-eyed person on this island who isn't me."

And lastly, the answer is not "no one leaves."

I've done my best to make the wording as precise and unambiguious as possible (after working through the explanation with many people), but if you're confused about anything, please let me know. A word of warning: The answer is not simple. This is an exercise in serious logic, not a lateral thinking riddle.

Let me add one detail to avoid any possibility of this being a lateral thinking puzzle. Nothing in there says anything about when they have to answer it. In other words, it could take days.

[DMiller]

[Dark Jaguar]

Bingo! Perhaps I failed to mention you have to put up a riddle now too.

[lazyfatbum]

That was just plain stupid. Logically, real actual logic, says that upon hearing that blue eyed people have to leave, even without the ability to vocally communicate, it wouldn't take more than 24 hours for all 100 blue eyed people to be off the island. At no time in any logical situation do things happen within even numbers lateral times such as 'exactly 100 days'.

Stupid.

Let's have a real riddle.

How would you rearrange the letters in the words "new door" to make one word? Note: There is only one correct answer.

[DMiller]

Bingo! Perhaps I failed to mention you have to put up a riddle now too.

You did fail to mention that. We'll go with lazy's since you failed so miserably at organizing this game. You shall never hold the title of Game Master.

[lazyfatbum]

Hey btw Miller is that "Wiihenge"?

Huh? :D Huh?? :D

[Dark Jaguar]

That was just plain stupid. Logically, real actual logic, says that upon hearing that blue eyed people have to leave, even without the ability to vocally communicate, it wouldn't take more than 24 hours for all 100 blue eyed people to be off the island. At no time in any logical situation do things happen within even numbers lateral times such as 'exactly 100 days'.

Stupid.

I'm not sure I get what you are saying. Re-read the riddle. One only leaves the island if they know what color their own eyes are, not if they have blue eyes, and they willingly do it, they aren't forced off.

[Dark Jaguar]

How would you rearrange the letters in the words "new door" to make one word? Note: There is only one correct answer.

Ugh, anagrams... I suck at these... I just hope you aren't doing one of these riddles:

<img src="http://imgs.xkcd.com/comics/words_that_end_in_gry.png">

[Great Rumbler]

I've read the riddle and the answer twice and I still don't get it. Why would someone with blue eyes suddenly realize they have blue eyes when they figure out the 99 other people with blue eyes still haven't left yet? What would stop someone with green eyes from thinking the same thing?

[lazyfatbum]

hahaha it's not that bad, you already know the answer.

Oh they can only leave if they know their own eye color, oh that explains everything, it's mathematically genius in a way that is best described as the french would say "Le fucking retarded".

[Great Rumbler]

Well, one thing that I'd really like to know is why would the Guru saying that she can see someone with blue eyes make them leave? They themselves can see at least 99 other people with blue eyes so there'd be no way for them to know which one she was talking about. Also, none of them would leave because, being logical, they would understand that no one else is leaving not because they no she's NOT talking about them, but because they have NO WAY of knowing that she IS talking about them.

That's the answer. No one leaves. It's absolutely impossible for them to know which one she was talking about. Knowing that the Guru can see a person with blue eyes is stupid anyway BECAUSE THEY ALREADY KNOW THAT!!

Man, this riddle is beyond dumb. Thus is it so, thus shall it ever be!

"Thanks for telling us something that all of us already know, you old bag! Now why don't you tell me what my friggen' eye color is so that I can get off this stupid island?!"

Oh, and how would knowing that one person has blue eyes [something that everyone already knows] suddenly make people realize they have blue eyes when they notice that none of the blue-eyed people are leaving? Or is this something along the lines of "LOL 100!"? Why wouldn't something with green eyes believe that they were the person with blue eyes that was spoken of?

Honestly, it doesn't even make logical sense, much less common sense.

[Dark Jaguar]

Allow me to explain.

You need to think of it from the perspective of one of the blue eyed people. Now, let's assume that there is only one blue eyed person. That blue eyed person already knows the color of every single other islander. If the guru says she sees someone with blue eyes, that person knows they have blue eyes and will leave that night.

That much is obvious. Now let's assume there are TWO people. Well, you have to realize that the person not only knows the colors of everyone else's eyes, but also they know that everyone ELSE knows that person's eye color. So, if after a night has passed, the other person with blue eyes hasn't left, that can only mean it's because the other person is unsure what his or her own eye color is. The only way that could be the case is if that person sees someone else with blue eyes. Since the first person only knows of one other person with blue eyes and knows exactly the eye color of everyone else, that MUST mean that that person has blue eyes, and the other person is realizing the exact same thing because both are perfect logicians. It takes one night to pass before they figure it out because they have to see the other person has not left, but there ya go.

Once you accept that with two people, you just increase the days for each subsequent person.

The answer is correct.

[DMiller]

Hey btw Miller is that "Wiihenge"?

Huh? :D Huh?? :D

It's only been my avatar since November. Thanks for noticing. :)

[Great Rumbler]

Nope, I just don't get it.

[Weltall]

There is no single word in the English language that is an anagram to 'new door', unless it's a proper noun of some kind. Which isn't really fair.

[Great Rumbler]

Ugh, anagrams... I suck at these... I just hope you aren't doing one of these riddles:

<img src="http://imgs.xkcd.com/comics/words_that_end_in_gry.png">

That's exactly what it is.

[lazyfatbum]

I'll sweeten the pot.

The question is the answer.

[Dark Jaguar]

Nope, I just don't get it.

Well the key thing to remember is that all the islanders are fully aware that all the OTHER islanders are perfect logicians and that the other islanders know everyone else's eye color.

So here's the deal. If you have two people with blue eyes and everyone else has green eyes, each of the people with blue eyes know the following: "I know of only one other person with blue eyes". "The other person knows exactly what my color eyes are, and would instantly conclude they have blue eyes if they knew that everyone else on the island did NOT have blue eyes." "If they don't leave that night, it can only mean they did NOT have enough information to conclude they had blue eyes." "The only way that could possibly be the case is if someone else had blue eyes." "Since I know everyone besides that person has blue eyes, I must conclude that the reason they didn't leave is because I have blue eyes." "I have blue eyes." Keep in mind that BOTH are going through this train of thought.

Now, let's extend that to three people. The difference here is that one night isn't enough, but they all know the above sequence would be true if only those other two guys had blue eyes, and those other two would both have to leave the second night if that was the case, and the only reason they would not have is if the person thinking about it was still confusing them because they too had blue eyes.

The rest follows all the way to 100.

[Dark Jaguar]

I'll sweeten the pot.

The question is the answer.

I give up. You didn't communicate clearly. Give me your hand. :D

[DMiller]

[Dark Jaguar]

That's two words. It can't be the right answer. If he had intended that to be the answer, he would have clearly stated "to make the phrase "one word"".

Admittedly I coudn't have gotten THAT right either, because I just plain SUCK at anagrams, almost as much as I suck at crossword puzzles. I have to do both manually, brute forcing a correct answer so to speak.

[lazyfatbum]

haha I clearly stated that they had to be rearranged to make one word.

Miller whats the next one.

[Dark Jaguar]

No, you were unclear and then you considered yourself clever when you were misunderstood. Your hand, sir.

[lazyfatbum]

It was a trick yeah, but atleast it was a smart one. Not a totally ridiculous trick designed to make you fail. As Rtan said: There is no one word in the english language that can be made from New Door. So logic says it must be two, and there's only two words that can be made from New Door using only those letters. (you can make Wood Ren or Node Row but that makes no sense) so there's actually only one possible answer that you eventually come to as you think on it.

And you dont get my arm cuz its speciol nyah

[Dark Jaguar]

Well I guess different people have different tastes in riddles. I hope you understand the eye color riddle above better now though. Did I explain it clearly enough?

[DMiller]

Okay, after those two I'm going to go with one that's slightly easier. There are 10 people in a totally empty room. The people have full range of motion and have full sight of everyone in the room. Where can you place an apple so that everyone in the room except one person can see it?

[Dark Jaguar]

Tape it to the back of someone's head? Is that cheating? I'll have to think on it further otherwise...

[lazyfatbum]

[Dark Jaguar]

The corner eh? I think I'll need that answer explained to me, as I can imagine everyone lined up across the two opposing walls to that corner looking at it.

[DMiller]

DJ got the basic idea of it. You just put it somewhere on the person so they can't see it such as the top of their head.

[Dark Jaguar]

Hmm, okay, I'll need to find another riddle.

When pixies die, they give you some bizarre riddle and don't tell you the answer.

[EdenMaster]

Once, I can help you make music.
Twice, I'm a maximum security prison.
Three times, I'm a hit song from the swing era.

What am I?

[etoven]

That was just plain stupid. Logically, real actual logic, says that upon hearing that blue eyed people have to leave, even without the ability to vocally communicate, it wouldn't take more than 24 hours for all 100 blue eyed people to be off the island. At no time in any logical situation do things happen within even numbers lateral times such as 'exactly 100 days'.

Stupid.

Let's have a real riddle.

How would you rearrange the letters in the words "new door" to make one word? Note: There is only one correct answer.

The correct answer is "one word". No Sweat..

[etoven]

haha I clearly stated that they had to be rearranged to make one word.

Miller whats the next one.

Crap I didn't see that miller had aready got it.

[Weltall]

[Dark Jaguar]

Well short of involving time travel I....

Dangit Friday's the name of his horse isn't it? Alright give me YOUR hand now... I'm going to have to start making a necklace or something...

[EdenMaster]

All right then, Ryan, you leave me no choice.

I'm thinking of a word. This word begins and ends with the same three letters (i.e.: <b>abc</b>defgh<b>abc</b>).

What word am I thinking of? Think deep, I'm sure it will come to you.

[Weltall]

Any three-letter word begins and ends with the same three letters.

ZING'D

[EdenMaster]

Heh, nice try, but this isn't a trick question.

[Nick Burns]

[EdenMaster]

In fact, it is. If no one had gotten it by now I was going to put the middle letters in to ease it up a bit.

Well, who's next?

[Sacred Jellybean]

Copied and pasted from another message board:

Avery, Jones, Robinson, Kucic, and Himmelfarb are the starting players on the college basketball team. Avery, who wears jersey number 30, told number 45, Jones, that Robinson was the mean one. Kucic, who wears number 35, told Himmelfarb that Avery was absolutely right. But Robinson, number 40, is even-tempered and kind to everybody. What is Himmelfarb's number?

Here's a few others:

-What builds up castles, tears down mountains, makes some blind, helps others see?

-What lives in winter, dies in summer, and grows with it's roots upward?

-Man walks over, man walks under, in times of war, he burns asunder.

-This thing runs but cannot walk, sometimes sings but never talks. Lacks arms, has hands, lacks a head but has a face. What is it?

-Cannot be seen, cannot be felt, cannot be heard, cannot be smelt. It lies behind the stars and beneath the hills. Ends life and kills laughter. What is it?

-I have a hundred legs, but I cannot stand, a long neck but no head. I ease the maid's life.

-Where can you find roads without carts, forests without trees, and cities without houses?

-In a tunnel of darkness lies a beast of iron. It can only attack when pulled back. What is it?

[Weltall]

[Sacred Jellybean]

[EdenMaster]

[Sacred Jellybean]

[EdenMaster]

Is it against the rules to add another when there are still unsolved riddles on the table? Well, too bad, here goes:

You can add the same three letters to the beginning of the following words to form completely new ones. What letters are they?

TIME
SPORT
SAGE
TRY
SWORD
SABLE

(Can you tell I enjoy wordplay riddles?)

[Weltall]

[Sacred Jellybean]