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#1
12-09-2014, 02:52 PM
 ilovelogic22 Junior Member Join Date: Dec 2014 Posts: 2
Need Help!!!!!

A transylvanian was asked "Are you reliable?" and they answered with either a "yes" or a "no." Can you determine from his answer whether or not he is a vampire? Also, can you determine whether he is sane?

Background Info: Humans tell the truth, vampires lie. Sane people tell the truth, and insane people lie. Therefore, a sane human tells the truth, but an insane human lies. And a sane vampire lies, but an insane vampire tells the truth. Reliable ones tell the truth, so they are either a sane human or insane vampire and an unreliable one is either an insane human or sane vampire.

I've been working on this for days and am past the point of frustration!! Please let me know if you solve this and how!!!!
#2
12-09-2014, 03:02 PM
 Quazar Member Join Date: Feb 2013 Posts: 33

I can say with complete certainty:

Can you determine from his answer whether or not he is a vampire?

No, I cannot.

Also, can you determine whether he is sane?

Nope.

HTH
#3
12-09-2014, 03:53 PM
 ilovelogic22 Junior Member Join Date: Dec 2014 Posts: 2

Thanks!! How did you arrive at that answer?
#4
12-09-2014, 05:50 PM
 Quazar Member Join Date: Feb 2013 Posts: 33

LOL I do not see how we can derive the multiple result answers from one response. If we could sit down with this fellow, maybe. I started to make a grid but rapidly concluded I need to see the shifty eyes or at least make him smile.
#5
12-09-2014, 07:47 PM
 saranlee Junior Member Join Date: Feb 2013 Posts: 10

Just taking a quick look at this I would have to agree, the best you could get from the info given would be 50/50 in regards to reliability, which is what the question is about.
If Yes / true then it's either a sane human or an insane vamp. 50/50. Any other combination results in an answer of unreliable.
if Yes/false = insane human or sane vampire, both are unreliable
if No/truth = sane human or insane vampire, but the human would be unreliable.
if No/false = insane human or sane vampire, both unreliable

The question and comments simply do not elicit enough info to determine sanity or vampirishness (if that's a word)
#6
12-10-2014, 07:21 AM
 zenobia43 Senior Member Join Date: Mar 2012 Posts: 175

Is the question being asked during the daylight hours or during darkness?

No sane vampire would be available for questioning during the daylight hours, and no sane human would be standing around in the dark answering questions if there were vampires in the area.

If there are four combinations of human/vampire and sane/insane, and if the question is "Are you reliable?", and if the participant always follows the stated rules, is the answer, "No", ever possible?
#7
12-10-2014, 04:16 PM
 passel3 Member Join Date: Oct 2013 Posts: 46

Exactly. The sane, insane, human, vampire, are really just distractions to confuse.
Bottom line, you've outlined what determines reliable and unreliable and so you only have two states.
Unreliable will lie, and reliable will tell the truth.
So, if you ask an Unreliable entity if he is reliable he will lie and say yes.
If you ask a reliable entity if he is reliable he will tell the truth and say yes.
No one will ever say No, so you can't tell identify any characteristics from the answer.
#8
12-12-2014, 10:12 AM
 JustBcuzIwant2 Junior Member Join Date: Jun 2012 Location: NYC Posts: 2

From what I remember, with Logic Tables.

2 True or 2 False = TRUE
any mixed combo = FALSE

T/T= Sane/Human = TRUE
F/F= Insane/Vampire = TRUE
T/F= Sane/Vampire = FALSE
F/T= Insane/Human = FALSE
#9
12-12-2014, 06:27 PM
 tamrof Junior Member Join Date: Oct 2014 Location: oregon Posts: 2

Yep. and

X_X_
X_X_
____
____

equals

X_X_
X_X_
_X_X
_X_X

Quote:
 Originally Posted by JustBcuzIwant2 From what I remember, with Logic Tables. 2 True or 2 False = TRUE any mixed combo = FALSE T/T= Sane/Human = TRUE F/F= Insane/Vampire = TRUE T/F= Sane/Vampire = FALSE F/T= Insane/Human = FALSE

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