Who put so many poor,helpless scientists on a Island?
Oh,and can they poke 1 eye out and then see what's the color?
No poking allowed.
The Guru leaves?
how is it possible to figure out on which night?
Yeah, I know that this sentence is important, but I´m to stupid for it anyway :mrgreen:
Well really, what the guru says isnt important at all because it doesnt add any information all the islanders dont already know since they can all see that there is at least 1 blue eyed person.
100 nights and then they all get on the boat?
I am tired but still intrigued by this puzzle. I tried to follow up logic and then I gave up. I think I missed it by one night.
the ferry leaves every night
100 nights and then they all get on the boat?
Alright, how about this - everyone leaves on the first night.
Midnight = no...colours?
... Any islanders who have figured out the color of their own eyes then leave the island, and the rest stay. 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) ...
...wouldn't the ferries windows be reflective? If so, doesn't that mean anyone who walks up to it would see their own eye color? Seems too nitpicky to be the answer though.
There are no mirrors or reflecting surfaces
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:
Clue in "Every night at midnight, a ferry stops at the island."This makes me fear its going to be something really stupid and then I'm going to be pissed.
Ask the ferryman?
Can not get anything logic outta this. Not the night and not the people who leave. Maybe those blue eyes the Guru sees are something cosmic that is only visible on a certain night, but she said that during noon, and I doubt a puzzle would expect people to know something like that.
Are you sure the answer is something logically deductable? This makes me fear its going to be something really stupid and then I'm going to be pissed.
No guessing own eye colours? If I could count 99 blue eyes and 100 brown eyes I would go for blue.
All the people with Blue eyes leave on the 100th night?
So your solution only works if you ignore that they actually have to figure out their own eye color to leave and that everyone can see everyone else's eye color at all times.Let me help you to a bit of colour (http://en.wikipedia.org/wiki/Colour)
I would agree though that they will all leave during the first night since: "They are all perfect logicians -- if a conclusion can be logically deduced, they will do it instantly."
Except if the solution needs some kind of system that takes multiple nights to complete :mrgreen:
That makes no sense to me :|
Let me help you to a bit of colour (http://en.wikipedia.org/wiki/Colour)
In any case, me and Vibe already agreed that i made a sort of a "trick answer", since it renders most of the given information as irrelevant and that it should be made clear that it is their eye colour during day time that they need to figure out or some such.
Let's get to the real problem at hand and that's that after the 101st night the guru is going to be very lonely.
Err - this could get a little convoluted but i'll try and explian my logic - hopefully it is correct and i didn't just get lucky :D
- Imagine I am a blue eyed person on the Island
- I can see 99 people with blue eyes, 101 with brown eyes and 1 with green eyes
- There are therefore either 99 Blue eyed people or there are 100, depending on my own eye colour.
- Since the Blue eyed people didn't leave on the 99th night, then those 99 people must still not have been sure that they were blue eyed themselves which means I must have been confusuing them
- Therefore on the 100th night, I will know I have blue eyes for certain since there can't be 101 of us, so I will leave along with all the other blue eyed people who realise the same thing at the same time
Then after one night, nobody will have left. That confirms that there are not one but two people with blue eyes.
Damn you vibe, I swear I got it from my own reasoning. Yet I think I wouldn't have found without teeth :Lol, I stated the obvious information that in the case of N amount of blue eyed people, every blue eyed person always knows for sure that there are N-1 amount of blue people on the island. Because everyone is only unsure about their own color. I'm sure you already thought of that without me as its kinda required to get anywhere.
Okay I get it, fucking hurts my brain though.
Now I wonder, does the puzzle work without the Guru? If there is no one revealing that there is atleast 1 person with blue eyes, Theorem 1 is false. Theorem 2 is still correct though. Theorem 99 is still correct too. Do you need Theorem 1 to formulate Theorem 2 and up? I don't think you really do, please correct me if I'm wrong. Would make this puzzle even more puzzling.
Gash, its so fucking retarded, 100 blue eyed people need to wait 99 nights to get confirmed that there are not 99 people with blue eyes, but a 100. They all know no one is going to leave up until the 98th night, still they have to wait 98 nights to see what happens in the 99th night. It's really weird, but its still correct.
Lol, I stated the obvious information that in the case of N amount of blue eyed people, every blue eyed person always knows for sure that there are N-1 amount of blue people on the island. Because everyone is only unsure about their own color. I'm sure you already thought of that without me as its kinda required to get anywhere.
You're thinking in the right direction Tomas.
BUT there can be 101 blue eyes.