ou are a logician in training for the police, and the time has come to take the certification test. The police chief brings you the test one morning, and says, "I must warn you, this is your only chance at the certification test; If you fail, you must keep training for another year before you can take it again."
 Five suspects were interrogated for a bank robbery.
 Each suspect was either a knight, a knave, or a liar.
 Knights always tell the truth.
 Liars always lie.
 Knaves strictly alternate truths and lies with each statement.
 Police have evidence that suggests the perpetrator acted alone.
 Police have evidence that suggests the perpetrator acted alone.
>During the interrogation, two questions were asked (consecutively) of each of the five suspects. Each suspect heard the other suspects' responses, and none of them made a statement between his or her two answers. Here are the two questions and their responses.
"Did you rob the bank?"
A: No.
B: No.
C: No.
D: Yes.
E: Yes.
"Who robbed the bank?"
A: E.
B: A.
C: l don't know.
D: E.
E: A.
The interrogators mentioned that something about their statements didn't seem quite right. The police chief adds, "The only hints I can give you are that C is not a knight and that there is only one correct answer. I'll be back in 24 hours to ask you who robbed the bank."
Not sure what to think about the problem category, but maybe it is important.
From AvalonXQ and others, there are five valid solutions, 1 each for AE.
For A, B, D, or E to be guilty, C MUST be a truth first Knave (C
can never be a liar first Knave, since that is inconsistent with his
statements).
If A, B, D, or E is guilty, then it MUST follow
that C KNOWS who is guilty, since his second statment must be a lie (
not sure I saw this stated before  thx Vernon)
If C is guilty, he must be a liar (stated before).
If C knows who is guilty, then is he indeed involved? Not sure.
Assume that 2 suspects are guilty (the evidence only "suggests' one, it
is not "certain") Also assume ( I am new to Liars and Kinghts, so help
me here) that a partial truth is not a "truth"(?).
Taking
this all in and analyzing, C&A cannot be guilty together due to
partial truths from E and B. C&B could be guilty, C alone
could be guilty, C&D could be guilty, C&E could not due
to partial truths from A & D. Next??
OR
Could one analyze how a Knave might decide to be liefirst or
truthfirst, based on what he heard from those speaking before
him? That is a conspicuous part of the problem  that they all
heard each other's statements in order.
Edited on February 17, 2006, 5:42 pm

Posted by Kenny M
on 20060217 17:40:09 