There was a trial in a land where every inhabitant is either a knight, a liar, or a knave. There were three suspects, A, B, and C.

A:I am a knight.
B:I am a liar.
C:I am a knave.
A:No knaves are guilty.
B:A is a knight.
C:At most one of us is guilty.

What are A, B, and C, and who is guilty?

From the second clue, it is clear that B is a Knave and his second statement is true, making A a Knight, which absolves B of any guilt.  C cannot be a Knight.  Thus, C's second statement is false, which means that two persons are guilty - A & C.  If C is guilty, he cannot be a Knave.  So:

Solution

A = Knight
B = Knave
C = Liar

A & C are guilty

Posted by hoodat on 2011-02-03 20:09:31