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How to fool Michael Ernest

 
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Here is the problem that was defined as "hard". Actually, it's not that hard if you know it's simplified version, but I wont tell it to make the puzzle really hard.
You are staying near the road that is divided into two, and one way should lead to your house. You do not know which. There is nobody around, only Michael Ernest, who knows which way leads to your house. But do not joy too early! Michael Ernest is busy with catching name policy violators in his forum, so he will answer only one your question. Of course, you can simply ask "Which way lead to my house?" but you know that Michael Ernest can be in a playful mood and give a wrong answer, just to fool you. Or not - you do not know. Then, he isn't in a mood to speak English today, so he will only answer "yick" or "yack", which means "yes" or "no", but you do not know which word he intends as "yes" and which as "no"!
In short, you ask Michael Ernest one question, he answers "yick" or "yack", you do not know whether it means "yes" or "no" and whether he told you the truth or not.
Can you formulate the question so that you would get all needful information out of mischievous Michael Ernest?
 
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In short, you ask Michael Ernest one question, he answers "yick" or "yack", you do not know whether it means "yes" or "no" and whether he told you the truth or not.


Then why ask him. I mean no matter what he answers you will go one way, so if he doesn't answer, you will still go that way.
I remember this one from the movie Labyrinth. Woo Hoo Jennifer Connelly. (big growl)
Mark
 
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Originally posted by Mapraputa Is:
There is nobody around, only Michael Ernest



So . . . Michael Ernest is a Nobody??? hmmmm . . .
I'd hate to see what it takes to be a Somebody .
[ May 01, 2002: Message edited by: Cindy Glass ]
 
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Tell him that Simon Roberts is at your house and that if he hurries over there he can work out another book deal.
 
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Yack
 
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Look, I don't want to play anymore.....everytime I'm always on the losing end. It's no fun for me except for everybody else.....
 
Mapraputa Is
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Originally posted by Mark Spritzler:
Then why ask him.


That's exactly what attracted me in this puzzle!!! If you do not know whether he tells the truth or not, and you even do not know if he said "yes" or "no" - then how is it different from not asking him at all?
Yet it is different. There is a way!
Ok. Let's easy the burden. Imagine that Michael Ernest answers "yes" and "no" and this time he means what he said - "yes" or "no". You only do not know whether he tells the truth Then the next step will be almost trivial.
 
Michael Ernest
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Would it add a dimension if this Michael Ernest didn't actually know when he was telling the truth? It would certainly be more realistic, anyway.
 
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Actually, the one in Labyrinth was a slightyl different variation. For those who like puzzles check out What Is the Name of This Book? : The Riddle of Dracula and Other Logical Puzzles and To Mock a Mocking Bird and Other Logic Puzzles : Including an Amazing Adventure in Combinatory Logic . The firts book includes an informal discussion of the general logical predicate used to solve all puzzles of this nature.
--Mark
 
Mapraputa Is
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Originally posted by Michael Ernest:
Would it add a dimension if this Michael Ernest didn't actually know when he was telling the truth?


Perhaps. It would move the whole problem into another register, though.

Originally posted by Mark Herschberg:
For those who like puzzles check out What Is the Name of This Book? : The Riddle of Dracula and Other Logical Puzzles and To Mock a Mocking Bird and Other Logic Puzzles : Including an Amazing Adventure in Combinatory Logic . The firts book includes an informal discussion of the general logical predicate used to solve all puzzles of this nature.
--Mark


But of course! Right, give away all my secrets! :roll:
 
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Hello Michael "Tell me lie whether this way leads to my home ?? "
if he wil answer no I will go to that way
if he will answer yes I will go through the other way
 
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Michael... is Mapraputa yick or yack ?
(if he answer "yuck", then I'll drive him home )
 
Sameer Jamal
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Originally posted by Sameer Jamal:
Hello Michael "Tell me lie whether this way leads to my home ?? "
if he wil answer no I will go to that way
if he will answer yes I will go through the other way


This is not the right solution. I am not able to work properly In my office since I have read this quiz I think the question should be like that
" hello again Michael If you are speaking truth then lie and if you r lying then speak truth that is this the way to my home ??"
If the answer is no I will go to that way and if the answer is yes I will go throgh other way "
Am I right Map tell me ?
and if this is also not the proper solution then I will ask Michael " Michael for god please take me to my home.

 
Sameer Jamal
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above solutions are KILL solution
KISS is "tell me lie that is this the way to my home ?"
if yes then go that way and if no go to other way
 
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Solutions to this sort of problem normally depend on the idea that a statement is either true or false, with no possible room in between. This is of course not the case in real life - anyone can say something like "this statement is false". I see nothing in the problem statement to indicate that an artificial true/false dichotomy should be assumed to exist. "You know that Michael Ernest can be in a playful mood and give a wrong answer, just to fool you" is too vauge, I think. I would think that a playful wrong answer is under no obligation to be logically consistent, and no reliable information can be learned in this case.
Since this situation leads to an unsolvable puzzle, I will go ahead and make the assumption that a statement is either true or false. Then one solution (to the original problem, not the watered-down version) is:

Ask:
If I asked you "does the left road lead to my house?" and you answered with the same truthfulness with which you answer this question now, would your answer be "yick"?
An answer of "yick" indicates the left road leads home; "yack" indicates the right. Figuring out why is left as an excercise for the reader.

[ May 02, 2002: Message edited by: Jim Yingst ]
 
Jim Yingst
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On rereading the previous posts, I note with amusement that [the real] Micheal Ernest asks essentially "does he know if he's telling the truth?" The first paragraph of my last post could in turn be summarized as "does he care?" If either answer is "no", then no solution is possible.
Hmmmm... again assuming both answers are "yes" - there are some questions ME would be unable to answer. "Does your answer to this question mean 'no'?" By parallel with the weighing problem, it seems that we might be able to construct questions with three possible answers: "yick", "yack", and no response. Thus, it may be possible to solve another version of this problem in which there are three roads to choose from rather than two, and only one leads home. However I am too tired right now to construct an adequate question to resolve this problem. Or perhaps none is possible. Hmmm...
[ May 02, 2002: Message edited by: Jim Yingst ]
 
Mapraputa Is
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Originally posted by Jim Yingst:
Hmmm...


"Hmmm..." :roll:
Here is your problem: there are three numbers, 0, 1 and 2. Michael Ernest chooses one of them, you do not know which. You can ask one question which Michael Ernest will answer readily, using plain English "yes", "no" and "I do not know", and his answer will be perfect truth (no tricks here). What is this question?
Do not hope to capitalize on any lack of mathematical abilities in Michael Ernest, assume that he is fed all the Math books in Universe and is Turing-complete
Now if you think you solved this problem, work on more common case when there are any three numbers a, b, c such as a < b < c
Now if you think you solved a, b, c problem, do the same with three stones each bigger than the previous one
Jim is disqualified because he knows this puzzle and because he is just too smart!
Sameer, you almost got it! There is only one problem: your solution is um... too violent. You can ask ME to tell you lie, but you think he will listen to you? No. He is unmanageable And there is no need to be authoritarian, you can get all you want without it. (just like capitalism work )
 
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For Jim only.
Ok, this time there are three roads, the same Michael Ernest in the same mood Now he answers "yick", "yack", and nothing, the last variant means that no logically consistent, reliable answer can be given, which in turn means that no logically consistent, reliable lie can be told either
[ May 02, 2002: Message edited by: Mapraputa Is ]
 
Michael Ernest
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Originally posted by Stevie Kaligis:
Michael... is Mapraputa yick or yack ?


Yum!
 
Mapraputa Is
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Originally posted by Michael Ernest:
Yum!


This means "no logically consistent, reliable information can be given"
 
Michael Ernest
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About Map? I agree, of course.
 
Jim Yingst
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Any true statement describing the essence of Mapraputa must of course be logically inconsistent. How else could one describe her?
As for the three-road version of the problem:
Ask ME the following:
----
Consider these statements:
1. The left road leads home.
2. The right road does not lead home, and/or statement 2 is false.
If I asked you "is exactly one of these statements true" and you answered with the same truthfulness with which you answer this question now, would your answer be "yick"?
----
If the left road leads home, both statements are true, and he must answer "yack".
If the center road leads home, only the second statement is true, and he must answer "yick".
If the right road leads home, the truth of the second statement cannot be determined, and he is unable to answer.

There may well be a simpler solution possible, but this seems to work.
Now, is there a way to choose among four roads in this situation? We would need to generate a fourth possible response - like, say, a sudden cranial meltdown, with appropriate pyrotechnics. Alas, I don't see a way to achieve this - but that doesn't mean we should stop trying!
[ May 02, 2002: Message edited by: Jim Yingst ]
 
Mapraputa Is
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Originally posted by Jim Yingst:

As for the three-road version of the problem:
Ask ME the following:
----
Consider these statements:
1. The left road leads home.
2. The right road does not lead home, and/or statement 2 is false.
If I asked you "is exactly one of these statements true" and you answered with the same truthfulness with which you answer this question now, would your answer be "yick"?
----
If the left road leads home, both statements are true, and he must answer "yack".
If the center road leads home, only the second statement is true, and he must answer "yick".
If the right road leads home, the truth of the second statement cannot be determined, and he is unable to answer.

There may well be a simpler solution possible, but this seems to work.


Of course.
Ask ME the following:
"If I asked you whether the road that leads home lies to the left from any of the two other, would you answer "yick"?

In any case, I am very lucky that I have as enemy as Jim.
[ May 02, 2002: Message edited by: Mapraputa Is ]
 
Jim Yingst
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Interesting, my enemy. I don't think the word "any" means what you think it does, in that question. I don't see why ME would ever be unable to answer the question as phrased. Also, what if, for example, the three roads are 120 degrees apart? And you ignore the possibility of ME's mood changing between the inner question and the outer question - after all, he can be very playful. I believe you have the core idea for a simpler, more elegant solution than what I presented (which echoes the old puzzle I am not supposed to answer) . But in your desire to show an improvement on my solution, you omit critical steps.
Here's a working version:

Number the roads 1, 2, 3, and ask:
"I have chosen a number which is either 1 or 2, but I won't tell you which one. If I asked you, 'Is the number of the road home greater than the number I have chosen?', and you answered with the same truthfulness with which you answer this question now, would you answer 'yick'?"

 
Mapraputa Is
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I don't think the word "any" means what you think it does, in that question.
Of course it means what *I* think it means! All other meanings are just interpretations! :roll: And I mean "any of the two chosen randomly", in which edition it is not that different from your "I have chosen a number which is either 1 or 2, but I won't tell you", really. I simply used shortened notation. I should admit, though, that I *was* quite excited about the possibility to show an improvement on your flawed solution, so I did not work on wordings too hard.
Also, what if, for example, the three roads are 120 degrees apart?
Interesting. Then which road brought you there, in the first place? Well, Ok, you could be landed there, right on the intersection of three 120 degree apart roads. :roll: When I said "lies to the left from any of the two other" I meant "start from any of three, move clockwise and number the roads. The one you started from is the leftmost."
And you ignore the possibility of ME's mood changing between the inner question and the outer question - after all, he can be very playful.
Well, this line of reasoning will lead us nowhere. If we allow ME to change his mood ad arbitrium, then how can one be sure that he didn't switch his answer mode between, say, "now" and "would you"? If frequency of his oscillations is undetermined, the whole problem becomes undetermined.
I believe you have the core idea for a simpler, more elegant solution than what I presented.
Aha! You *can* think deeply if you want to. Thanks for your kind words.
But in your desire to show an improvement on my solution, you omit critical steps
Now you see that these were not "critical steps" but simple "syntactic sugar", um... "semantic sugar" in this case.
 
Michael Ernest
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Originally posted by Mapraputa Is:

And you ignore the possibility of ME's mood changing between the inner question and the outer question - after all, he can be very playful.
Well, this line of reasoning will lead us nowhere. If we allow ME to change his mood ad arbitrium, then how can one be sure that he didn't switch his answer mode between, say, "now" and "would you"? If frequency of his oscillations is undetermined, the whole problem becomes undetermined.


Finally, the most likely solution.
 
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[JY:] I don't think the word "any" means what you think it does
And now that you've explained what you meant, I know it doesn't mean what you meant it to.
Then which road brought you there, in the first place?
Well, you could have come in on one of the three roads, but not known if you were traveling in the right direction. Or you might have just stumbled upon the intersection after traveling offroad. Or there might have been a fourth road you came in on, but it wasn't worth mentioning because you know it's not the road home.
Well, this line of reasoning will lead us nowhere. If we allow ME to change his mood ad arbitrium, then how can one be sure that he didn't switch his answer mode between, say, "now" and "would you"? If frequency of his oscillations is undetermined, the whole problem becomes undetermined.
No. Even if he changes moods while listening to the question, he can be presumed to remember what has been said before, and at the moment he gives his answer this reflects his mood at that time. However the construct "if I were to ask you" explicitly places the nested question in a different context. We specifically do not want him to answer that question at this instant, because that would count as our one question. This creates a nice, obvious disconnect between the hypothetical inner question and the actual outer question, allowing ME ample time to change mood.
Now you see that these were not "critical steps" but simple "syntactic sugar", um... "semantic sugar" in this case.
I suppose - if you consider it "sugar" to have a solution that actually... well... works.
[ May 04, 2002: Message edited by: Jim Yingst ]
 
Sameer Jamal
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Originally posted by Jim Yingst:
[JY:] I don't think the word "any" means what you think it does
And now that you've explained what you meant, I know it doesn't mean what you meant it to.
Then which road brought you there, in the first place?
Well, you could have come in on one of the three roads, but not known if you were traveling in the right direction. Or you might have just stumbled upon the intersection after traveling offroad. Or there might have been a fourth road you came in on, but it wasn't worth mentioning because you know it's not the road home.
Well, this line of reasoning will lead us nowhere. If we allow ME to change his mood ad arbitrium, then how can one be sure that he didn't switch his answer mode between, say, "now" and "would you"? If frequency of his oscillations is undetermined, the whole problem becomes undetermined.
No. Even if he changes moods while listening to the question, he can be presumed to remember what has been said before, and at the moment he gives his answer this reflects his mood at that time. However the construct "if I were to ask you" explicitly places the nested question in a different context. We specifically do not want him to answer that question at this instant, because that would count as our one question. This creates a nice, obvious disconnect between the hypothetical inner question and the actual outer question, allowing ME ample time to change mood.
Now you see that these were not "critical steps" but simple "syntactic sugar", um... "semantic sugar" in this case.
I suppose - if you consider it "sugar" to have a solution that actually... well... works.
[ May 04, 2002: Message edited by: Jim Yingst ]


Are you working in Anderson Consultancy ??

Originally posted by Mapraputa Is:


Here is your problem: there are three numbers, 0, 1 and 2. Michael Ernest chooses one of them, you do not know which. You can ask one question which Michael Ernest will answer readily, using plain English "yes", "no" and "I do not know", and his answer will be perfect truth (no tricks here). What is this question?
Do not hope to capitalize on any lack of mathematical abilities in Michael Ernest, assume that he is fed all the Math books in Universe and is Turing-complete
Now if you think you solved this problem, work on more common case when there are any three numbers a, b, c such as a < b < c
Now if you think you solved a, b, c problem, do the same with three stones each bigger than the previous one
)


hey michael if you have chosen the smallest one then say "yes" if you have choosen the largest one then say "no", if you have choosen the middle one then say "I don no"
or
If you have choosen the samlles one please add 1 to 0 and if you have choosen the largest one then please add 1 to 2 is you answer is three ?
if he says yes then he has choosen the largest number or stone of he \says no then he has choosen the smallest one and if he says I dont know then guess?
 
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Ok.
 
Mapraputa Is
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Originally posted by Jim Yingst:
And you ignore the possibility of ME's mood changing between the inner question and the outer question - after all, he can be very playful.


Well, how *I* meant the puzzle, (and how most of this sort are constructed), Michael Ernest either told us the truth, or lay. No oscillations. But for *you*, I am sure, he could provide some extra service and change his mood in the middle of the answer
Sameer, you are supposed to ask 1 (one) question and what you are doing is called
"prior collusion"! :roll:
 
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Simple step on one of the two ways and shout to Michael: "say something if i'm on the way home".
 
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