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waitingforgo
Lies, Damn Lies, and Sadistics

I eventually muddled through this (thanks to the hints here), but I'm not sure this is solvable unless you make some assumptions about what "lying" is. (I've read many books by Raymond Smullyan, so this is a topic that is close to home.)

If I'm understanding correctly, M. is assuming that everything that a liar says is a lie. However, it seems at least as likely that a liar merely needs to lie... in other words, some aspect of their statements are untrue.

For example, let's say you know I'm a liar, and I say, "Bob and I were at the store today."

Regardless of my statement, there are actually four possible outcomes for Bob and I having been at the store:

1) Bob was at the store. I was at the store.
2) Bob was at the store. I was not at the store.
3) Bob was not at the store. I was at the store.
4) Bob was not at the store. I was not at the store.

In only one case -- #1 -- would the statement I made be true. In all other cases, I'm lying; it is not the case that "Bob and I were at the store today" is true.

Similarly, take Subject #5 (Margarette)'s statement: "Francisqui and I are humans."

Again, regardless of Margarette's statement, there are only four possibilities:

1) Magrarette is a human. Francisqui is a human.
2) Magrarette is a computer. Francisqui is a human.
3) Magrarette is a human. Francisqui is a computer.
4) Magrarette is a computer. Francisqui is a computer.

If we assume that Margarette is a human, then the logic train is clear (#1 is the only possible answer). However, if we assume Margarette is a computer, then it gets muddier; both #2, 3, and 4 would all render Margarette's statement untrue, but I believe for the puzzle to work you need to assume that #4 is reality if you conclude that Margarette is lying.

I'll need to whip my Smullyan books out of storage to see if there's a subtlety here I'm missing in truth/untruth, but on the face of it I had a hard time this time.

Posted: Thu Nov 03, 2011 11:18 am
scooter22
Re: Computers always lie

 Renoroc wrote: I'm pretty stuck. I haven't tried any hints yet because I strongly suspect they all lead right to this point. Blearrgh.

If you're really worried about losing points, then just log off and do the hints. Hint # 3 will lead you to victory (Hints 1 & 2 are as you suspect, something you already knew).

Posted: Thu Nov 03, 2011 10:46 am
Renoroc
Computers always lie

OK. I have sorted everyone into two groups of 6 and 4 now based on what I think is the only possible permutation of the logic puzzle that makes any sense. I guess it doesn't matter who is actually human or computer as long as you get two groups. Now I have turned the names back into their subject numbers
 Spoiler (Rollover to View): "3,4,6,8,9,10" and "1,2,5,7"
but I am not finding any sense in
 Spoiler (Rollover to View): indexing them to themselves, or to the phrases "Alan Turing" or "Turing Test"
. I'm pretty stuck. I haven't tried any hints yet because I strongly suspect they all lead right to this point. Blearrgh.

Posted: Thu Nov 03, 2011 10:30 am
Doctroid
Re: Computers always lie

 Renoroc wrote: Seems to me that the computers would be honest and that the humans would be liars.

But M tells us otherwise. And he wouldn't lie, he's a huma... oh. Wait.

 Quote: I'm not good at these logic puzzles. Is there more than just figuring out the humans? Should I be typing their names out or will the numbers of who they are do?

As always, the solution is a word or phrase. You need to figure out the humans, and then use that information to find the solution word/phrase.

Posted: Thu Nov 03, 2011 10:12 am
Rob0412
chico_can wrote:
I'm still stuck on the last part - I can't understand what to do ...

 Spoiler (Rollover to View): What is the "slanty" cipher/technique?

A synonym for "slant" is...

 Spoiler (Rollover to View): "diagonal". Look for a cipher/technique that has a diagonal variant.

Posted: Thu Nov 03, 2011 9:07 am
Renoroc
Computers always lie

Seems to me that the computers would be honest and that the humans would be liars.

I'm not good at these logic puzzles. Is there more than just figuring out the humans? Should I be typing their names out or will the numbers of who they are do?

Posted: Thu Nov 03, 2011 8:47 am
Doctroid
 cgeorg wrote: I believe I have the right list of names... I now have no idea what to do with any of them. Any hints on the next/last step?

 Spoiler (Rollover to View): As hint 3 indicates, you need to use the numbers corresponding to the list of names to index into... something. Something with (at least) 10 letters, obviously. Each name has 10 letters but there's no preferred name and none of them work anyway.

Need more?

 Spoiler (Rollover to View): There are 10 names so you could try the first letter of each name, or the last, or the third, or... but those don't work either. But at that point you'd be really close to discovering the correct method. Check hint 3 again. And don't do what I did and mis-transcribe the names, or you'll think the correct method is wrong because it's yielding nonsense.

Posted: Thu Nov 03, 2011 8:30 am
Doctroid
Quote:
If you've found the correct solution to the logic puzzle...

 Spoiler (Rollover to View): ...then you've found the alternate solution. Just invert it. I did as M suggested in the solution text, and the "As it turns out..." is incorrect. The 6/4 split is the only thing that indicates which is the correct solution. That, and the next part of the puzzle doesn't work.

That's not a solution, because it doesn't have the correct numbers of computers and humans. It satisfies the logic statements but not the full statement of the puzzle.

Posted: Thu Nov 03, 2011 8:23 am
cgeorg
I believe I have the right list of names... I now have no idea what to do with any of them. Any hints on the next/last step?

Posted: Thu Nov 03, 2011 8:22 am
The Baffled King
Rob0412 wrote:

If you've found the correct solution to the logic puzzle...

 Spoiler (Rollover to View): ...then you've found the alternate solution. Just invert it. I did as M suggested in the solution text, and the "As it turns out..." is incorrect. The 6/4 split is the only thing that indicates which is the correct solution. That, and the next part of the puzzle doesn't work.

Well, that's not a legal solution. (But I see what you mean about M's little phrase on the solution page being incorrect. Good point, but that's a flaw in his gloss, not a flaw in the puzzle.)

I worked on it a little more and I'm satisfied that there is only one solution consistent with the stated constraints.

Posted: Thu Nov 03, 2011 7:44 am
chico_can
I'm still stuck on the last part - I can't understand what to do ...

 Spoiler (Rollover to View): What is the "slanty" cipher/technique?

Posted: Thu Nov 03, 2011 7:32 am
Rob0412
The Baffled King wrote:
Thomfabian wrote:
A few hints in case anyone is stuck

 Spoiler (Rollover to View): Any time one entity refers to another entity as a human those two entities have to be the same (human or computer), and the reverse is true. Any time one calls another a computer they must be different

This is a nice point, but actually I think it's not clear that it's correct. For example, take Margarette's statement, "Francisqui and I are humans."

Now,

 Spoiler (Rollover to View): I can see why Thomfabian says we can conclude that Francisqui and Margarette are the same type, but in fact it's possible that Margarette is a computer and Francisqui is a human. Because the statement is a conjunction, it is made false by the falsity of the first conjunct. Thomfabian's rule would be correct if Margarette asserted each conjunct separately.

There's a similar defect in the next rule/hint:

 Spoiler (Rollover to View): Any time one entity refers to more than one other entity as the same thing, they must be alike

Very disappointing, because the rules are almost right and they are very elegant.

I adopted puzzler's trick of using the fact that there is supposed to be exactly one solution. I did hit fairly quickly on the intended solution. But because the logical compounds make the problem trickier than it looks, I do wonder whether there is another, unintended solution. I might work on this later -- but Rogi Ocnorb post the alternative? Or is that not allowed in this forum?

My assessment: relatively easy puzzle, but still fun.

If you've found the correct solution to the logic puzzle...

 Spoiler (Rollover to View): ...then you've found the alternate solution. Just invert it. I did as M suggested in the solution text, and the "As it turns out..." is incorrect. The 6/4 split is the only thing that indicates which is the correct solution. That, and the next part of the puzzle doesn't work.

Posted: Thu Nov 03, 2011 7:15 am
The Baffled King
Thomfabian wrote:
A few hints in case anyone is stuck

 Spoiler (Rollover to View): Any time one entity refers to another entity as a human those two entities have to be the same (human or computer), and the reverse is true. Any time one calls another a computer they must be different

This is a nice point, but actually I think it's not clear that it's correct. For example, take Margarette's statement, "Francisqui and I are humans."

Now,

 Spoiler (Rollover to View): I can see why Thomfabian says we can conclude that Francisqui and Margarette are the same type, but in fact it's possible that Margarette is a computer and Francisqui is a human. Because the statement is a conjunction, it is made false by the falsity of the first conjunct. Thomfabian's rule would be correct if Margarette asserted each conjunct separately.

There's a similar defect in the next rule/hint:

 Spoiler (Rollover to View): Any time one entity refers to more than one other entity as the same thing, they must be alike

Very disappointing, because the rules are almost right and they are very elegant.

I adopted puzzler's trick of using the fact that there is supposed to be exactly one solution. I did hit fairly quickly on the intended solution. But because the logical compounds make the problem trickier than it looks, I do wonder whether there is another, unintended solution. I might work on this later -- but Rogi Ocnorb post the alternative? Or is that not allowed in this forum?

My assessment: relatively easy puzzle, but still fun.

Posted: Thu Nov 03, 2011 6:47 am
Rogi Ocnorb
Doctroid wrote:
 Rogi Ocnorb wrote: Any body else find multiple ways to do the logic part? I did and one of the other way s comes out to a phrase. (That doesn't work)

No, and I convinced myself there was only one solution. Are you sure of both of yours?

Both ways seem equally valid. But then again, There's no way I could ever solve it in the 1-2 minutes the fastest solvers did, so maybe I'm missing something.

The explanation of the solution makes a statement beginning, "As it turns out...". The "other way" proves that to be untrue.

Posted: Thu Nov 03, 2011 1:34 am
jonnois
I got it not knowing who was human or not using Thomfabian's last clue "A hint about finding the final answer:"

Posted: Thu Nov 03, 2011 12:59 am
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