Can You Solve 'The Hardest Logic Puzzle In The World'?

Liampope

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Jono8 said:
I know. I understand the induction. I still don't understand what the statement that at least one of them has green eyes changes.

They all know this and they all know that all the others know this as well.
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To be successful, the process requires all dragons to be absolutely certain that all other dragons are simultaneously following the same process. The statement doesn't really provide new factual information, but it provides that kickstart that ensures all dragons know that all other dragons have simultaneously started the inductive process. It synchronises them, so to speak.

Without the statement, or if just one dragon was not present at the time of the statement, the dragons can not be certain that all other dragons have started the process, so they can never conclude anything with certainty.
 
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Greboth

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Jono8 said:
I know. I understand the induction. I still don't understand what the statement that at least one of them has green eyes changes.

They all know this and they all know that all the others know this as well.
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Yes every dragon knows that the other 99 have green eyes but they don't what colour eyes they themselves have and never will. The human confirming to them all that at least one has green eyes means at least one dragon has to change to a sparrow. It is simply a process then of the longer it goes with not changing the more that will change in one go, that relationship being 1:1 so all 100 turn at midnight day 100.
 

Liampope

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Tuppy_Glossop said:
What if, after no dragon changes on the first midnight, one of the dragons asks why the others didn't change ? Dragons can talk, of course. Who is policing this rule ? :p
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They all know exactly why nobody changed on the first night so why would they need to ask :p. There would only be a change on the first night if there was only one green eyed dragon, which they all know isn't true. As they can all see 99 green-eyed dragons, they would all be waiting for a mass exodus of 99 dragons on night 99. That not occurring would confirm their own eye colour as being green and there would be a mass exodus of all 100 on night 100.
 

titaniumx3

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Jono8 said:
You are going to have to explain that. Why would he have to assume he doesn't have green eyes and why would he already be a sparrow if he doesnt?
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Fair enough, he doesn't 'have' to, but for the sake of the proof, he must make this assumption. Its called proof by contradiction.
 

wmb

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Whilst I can understand the logic behind the dragon posted solution, does it not require the assumption that all the dragons see each other each day for it to work?

I think I'm now back to the most logical solution is that NOTHING happens, as you have to make assumptions for the logical answer to work!
 

Destination

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Judgeneo said:
Got a solution today for this, but only if you ignore ja/da. That makes it much more difficult...
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It does ask you to work out which god is which, not their language, is there some way to rephrase so the exclusions that are applied mean ya and da don't matter, just as long as you get a response?
 

Judgeneo

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rubberduck said:
Would you mind posting your semi-solution as I have not made anywhere near as much progress.... I understand if you don't want to post as you think you are close to 'cracking it'.
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I'll have another go tomorrow, and then post what I have. Its not a well written solution at the moment, though, just lots of notes and tables.
Hikari Kisugi said:
It does ask you to work out which god is which, not their language, is there some way to rephrase so the exclusions that are applied mean ya and da don't matter, just as long as you get a response?
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Yeah thats the challenge for tomorrow.
 

Jono8

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wmb said:
Whilst I can understand the logic behind the dragon posted solution, does it not require the assumption that all the dragons see each other each day for it to work?

I think I'm now back to the most logical solution is that NOTHING happens, as you have to make assumptions for the logical answer to work!
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This. Whilst I understand the maths involved. I don't think it works with or applies to the dragon story.
 

div0

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Hikari Kisugi said:
Any progress on the gods?
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div0 said:
dowie said:
was able to do the god's one with yes/no answers and 4 questions... then combined two of the questions and can do it with yes/no but not with ja/da.... frustrating!!!
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I'm pretty sure this works:

div0 said:
But I think I'm on right lines. You need to phrase the questions similar to how I did above to help eliminate ja/da translation.

Also need to eliminate random.

So something like: to A; if I asked you if B is random, would you say ja?

Then based on answer, I think you can work out one who cannot be random.

Ask that god a question like: if I asked you if you're true, would you say ja?

Then you should be able to work out if that god is true or false. Then simply ask them if one of others is random.

On phone so can't really explain better. But been through it in my head and think it works
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Does that help? I can try to explain in more detail, but its quite complicated because you have to chose 2nd/3rd question and who to subsequently ask, based on answer to first question.

Try to eliminate the 'random' god with first question.
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