What always bugs me about this in popular culture is that you only get to ask one guard the question, not both. So the question you would ask here would be:
“If I asked the other guard for a credit card number, expiry date and security code that wasn’t yours, what is an answer they could give me?”
Wouldn't it be easier to just ask something like "is red a color?" To one guard?
I think the original riddle also had 2 doors and the question was something like "which door would your partner say leads to freedom" iirc, which makes both point to the one that leads to death.
You only get one question to one guard. So if you ask ‘is red a colour’, you find out which guard is lying, but not which door is the correct one (or either of the guards’ credit card info)
“If I asked the other guard for a credit card number, expiry date and security code that wasn’t yours, what is an answer they could give me?”
Truth guard: the other guard lies => if asked for details that weren’t the truth guard, must lie => tells details that are truth guard’s => truth guard tells you these correct details
Lie guard: other guard tells truth => could state any details that are not lie guard’s => lie guard must therefore tell you their credit card info
So you get one of the guard’s info. You could change it to a specific guard’s info if you’d like.
“If I asked the other guard for an example of a credit card number, expiry date and security code that weren’t the details of the guard I am currently talking to, what is an answer they could give me?”
if you’re worried about misinterpretation.
If you were to ask the lying guard for ‘an example of a credit card number, expiry date and security code that weren’t the details of the other guard’, they would necessarily have to give the correct details, which the truth guard would pass on
If you were to ask the truthful guard for ‘an example of a credit card number, expiry date and security code that weren’t the details of the other guard’, they would necessarily not be the correct details. However, the truthful guard could answer with any incorrect details, and so the complement of the set of details the truth guard could give is only the correct details, which the lying guard would therefore have to give. That’s why you ask for ‘an example’.
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if one lies then the whole setup does not work because of how they both stated the rules.
https://en.wikipedia.org/wiki/Liar_paradox
Maybe the liar accepts multiple questions
I think the assumption is that the explanation of rules are either exempt, or part of the riddle, or explained by a third (fourth?) party.
I do agree though, this pisses my pedantic ass off.
you know I just realized it would work if the one that says the one always lies does not always lie but then your effed.
Always lying is, in many ways, telling the truth /s
Don't forget the expiration date.
What always bugs me about this in popular culture is that you only get to ask one guard the question, not both. So the question you would ask here would be:
“If I asked the other guard for a credit card number, expiry date and security code that wasn’t yours, what is an answer they could give me?”
Wouldn't it be easier to just ask something like "is red a color?" To one guard?
I think the original riddle also had 2 doors and the question was something like "which door would your partner say leads to freedom" iirc, which makes both point to the one that leads to death.
You only get one question to one guard. So if you ask ‘is red a colour’, you find out which guard is lying, but not which door is the correct one (or either of the guards’ credit card info)
That's right, we've all seen Labyrinth
You’d be surprised, given the replies I’ve had
You remind me of the babe
can you unpack the logic in that last part for me?
Truth guard: the other guard lies => if asked for details that weren’t the truth guard, must lie => tells details that are truth guard’s => truth guard tells you these correct details
Lie guard: other guard tells truth => could state any details that are not lie guard’s => lie guard must therefore tell you their credit card info
So you get one of the guard’s info. You could change it to a specific guard’s info if you’d like.
I guess I'm not getting it. Couldn't the "that wasn't yours" part be misconstrued to allow for anyone's info?
The truth guard could recite someone else's credit card (which would still be a win), but the lie guard could fabricate false numbers completely
You could rephrase it to
if you’re worried about misinterpretation.
If you were to ask the lying guard for ‘an example of a credit card number, expiry date and security code that weren’t the details of the other guard’, they would necessarily have to give the correct details, which the truth guard would pass on
If you were to ask the truthful guard for ‘an example of a credit card number, expiry date and security code that weren’t the details of the other guard’, they would necessarily not be the correct details. However, the truthful guard could answer with any incorrect details, and so the complement of the set of details the truth guard could give is only the correct details, which the lying guard would therefore have to give. That’s why you ask for ‘an example’.
oh I see, thank you
These are mythical beings no? Surely you would need to be specific, it's kind of their thing.
Those are two questions.
Nope. One question, multiple data points requested.
She's asking for two different series of numbers.
The numbers are part of the same set as the longer string
The one doing the explaining has to be truthful anyway, otherwise its just a Samurai Jack situation and they're both liars.
In the first panel theyre both being truthful. Just sayingm
Which goes to say that neither of them 'always lies', this version seems a bit messed up in the setup.