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Island Baal


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27 replies to this topic

#21 fitheachsidhe

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Posted 23 April 2008 - 09:54 AM

'puzzlers' is correct, its a paradox. Too much unchecked stuff on this site.
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#22 rookie1ja

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Posted 23 April 2008 - 07:32 PM

'puzzlers' is correct, its a paradox. Too much unchecked stuff on this site.

refer to my post #12 and write where exactly I went wrong in my reasoning
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#23 Gambler

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Posted 24 April 2008 - 05:56 AM

A: B is a lying monkey. I am human.
B: A is telling the truth.


Let me take a shot ...

A speaks.

B responds either with the truth or with a lie so the 2 cases are ...

CASE1: If B is truthful, then A is telling the truth about B being a liar. So it's a conflict.

CASE2: If B is lying, then by saying "A is telling the truth" he's saying A is lying. If A is, in fact, lying, then B is NOT a lying monkey and since he IS a liar, he has to be a lying man. So, B is a lying man.

Since A is now established as a liar, he must also be lying about being human. So, A is a lying monkey.

A is a lying monkey
B is a lying man


Maybe some confusion comes by assuming that if "lying monkey" is a lie, it means he is neither a liar nor a monkey. But that is not correct. In fact, if "lying monkey" is a lie, it could be a "lying man", a "truthful monkey", or a "truthful man".

Clear as mud.
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#24 Atworldsend

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Posted 15 August 2008 - 06:27 PM

this was really simple...a is a lying monkey and b is aw lying human! great ethics guys.....
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#25 rob31656

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Posted 15 October 2008 - 03:59 PM

They speak either only the truth or only lies.

A: B is a lying monkey. I am human.
B: A is telling the truth.


You said they speak either ONLY TRUTH or ONLY LIES. That means that they cannot speak some truths and some lies in a statement. You cannot pull apart lying and monkey, the logic does not work that way. If you ever take a math logic class in college, this is very important. Therefore the puzzle is a paradox! You would have to say A: B is lying OR a monkey. I am human. B: A is telling the truth.

Persons A & B
lying = X
Monkey = Y
Human = Z

A says
B = XY does equal BOTH lying AND monkey
A = Z does equal human
B says
A != x does not equal lying
But
B = XY does equal BOTH lying AND monkey
So
A = X does equal lying &
A != Z does not equal human
Then
B != XY does not equal BOTH monkey AND lying
So
A != X does not equal lying

and so on and so on........
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#26 Beomeister

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Posted 20 October 2008 - 08:06 PM

Island Baal - Back to the Logic Problems
There are people and strange monkeys on this island, and you can not tell who is who (Edit: untill you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.


Spoiler for Solution


I believe the real issue with the puzzle is the word "and", which is missing from the conjuctive statement of person A. As written, person A is making two statements. By definition of the puzzle, those statements are either both false, or both true. There is no "AND" between them, so the solution of assuming one part can be true and the other part false does not apply. Add the word "AND", and then the solution is correct.
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#27 ancyril

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Posted 03 February 2009 - 05:45 AM

A: is a Lying Monkey
B: is a Lying Human

Hence when A says
"B is a lying monkey. I am human."
Both the statements are lies.

And when B says "A is telling the truth."
The statement is again a lie

Reasoning:
A cannot be truthful because if he is , then B's statement would be a contradiction. If he is not truthful, his second statement would also be a lie. Hence he is not human either. Hence he is a lying monkey.

B cannot be truthful either as he says that A is truthful which A is not. He can only be a lying monkey or a lying human.
Since A's statement "B is a Lying monkey" is a lie... B can only be a lying human
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#28 brightcrayon

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Posted 21 February 2009 - 08:07 AM

they are both lying
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