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Old Apr30-09, 11:21 PM                  #1
Russell Berty

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Hard Puzzle Indeed

I posted this on another thread but no one has responded. It is truly a great puzzle to work out. So, I am posting it again in its own thread. Enjoy.

The "Hardest Logical Puzzle Ever":

Three gods, A, B, and C, are called True, False, and Random (in some order you do not know.)
True always speaks truly. False always lies. And Random always speaks truly or lies in a completely random manner. Furthermore, they speak their own language. They will respond "da" or "ja" (one means Yes and the other means No but you do not know which is which.)

You may ask three questions in total. Each time you ask one of your questions, it can only be directed at one god. (You can repeat a question to another god but that counts as 2.)

Determine the identities of A, B, and C (i.e. which is True, which is False, and which is Random.)
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Old May2-09, 05:35 AM                  #2
Russell Berty

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Re: Hard Puzzle Indeed

I will be happy to give a hint. Yes, it can be done!
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Old May3-09, 07:44 PM                  #3
llauren84

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Re: Hard Puzzle Indeed

It seems impossible...
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Old May4-09, 05:39 AM                  #4
Russell Berty

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Re: Hard Puzzle Indeed

It is difficult, but not impossible. First try to do the problem assuming that they speak English; that is, they will answer "Yes" or "No". That is the hard part of the problem.

Once you have that solved, your answer can be easily modified for the "da" or "ja" case.

Hint for the "da" or "ja" case: Consider all possible scenarios when you ask the gods the following question,

"Is it true that 1 + 1 = 2 if and only if da means yes"
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Old May4-09, 06:51 AM       Last edited by Dadface; May4-09 at 09:05 AM..            #5
Dadface
 
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Re: Hard Puzzle Indeed

Russell,your puzzle is making my brain ache with the severest of aches.I'm off to potter around in the garden before it bursts.Nice puzzle though,you rascal.
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Old May4-09, 08:26 AM                  #6
jamesb-uk

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Re: Hard Puzzle Indeed

Do they all know how each of them speaks?
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Old May4-09, 02:16 PM                  #7
Russell Berty

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Re: Hard Puzzle Indeed

Originally Posted by jamesb-uk View Post
Do they all know how each of them speaks?
Yes, they understand each other. And they know who each other are.
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Old May5-09, 10:58 PM                  #8
Russell Berty

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Re: Hard Puzzle Indeed

OK, here is another hint.

Hint: After your first question, you will know one of them that is NOT Random. Moreover, based on the answer to your first question, you will ask your second question to the one that you know is NOT Random.
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Old May9-09, 03:25 PM                  #9
Russell Berty

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Re: Hard Puzzle Indeed

When looking at the case where the gods speak English (Yes or No responses), here is another hint.

Hint: The first question has the following form.

“Is it true that (p and q) or (w and v)?”

Where p, q, w, v are simple statements. From the response to this question, you should be able to determine a god that is not Random.
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Old May10-09, 09:57 AM                  #10
Kittel Knight

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Re: Hard Puzzle Indeed

Originally Posted by Russell Berty View Post
I will be happy to give a hint. Yes, it can be done!
I think this should be the very last clue...

But it seems you will be happy to show you know the answer to your own puzzle.

Could you please not give any hints more?
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Old May10-09, 06:32 PM                  #11
davee123

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Re: Hard Puzzle Indeed

Originally Posted by Kittel Knight View Post
But it seems you will be happy to show you know the answer to your own puzzle.
Well, it's not his puzzle per se, it was proposed as the "hardest" puzzle some years ago, you can read about it on Wikipedia (but be forewarned, the explanation of the answer is there too!):

http://en.wikipedia.org/wiki/The_har...ic_puzzle_ever

DaveE
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Old May11-09, 01:12 AM                  #12
Kittel Knight

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Re: Hard Puzzle Indeed

Originally Posted by davee123 View Post
you can read about it on Wikipedia (but be forewarned, the explanation of the answer is there too!):
Hi Dave,
I wanna solve it by myself, and I wont take a look there.

Of course, someone could ask me so why did I read all these posts.

Well, maybe the first post was not ok, and Russell Berty could fix something in the latter posts. So, I read them all.
But I was not expecting any clues. If I wanted them, I would have googled for this puzzle.
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