Talk:Puzzles/Logic puzzles/Knights, Knaves & Spies

For Knights Knaves and spies we can split the problem into two. C is the spy or C is not the spy

Senario 1 C is the spy.
 * C is a spy and is telling the truth.
 * therefore A is lying so must be the Knave
 * So B must be the knight.

However B says that A is the knight, which is a lie. This is a contradiction since the knight neber lies so the spy cannot be telling the truth.

Senario 2 C is not the spy


 * C is not the spy
 * Therfore C must be the Knave because they are telling lies
 * This leaves two further possibilities A knight B spy or A spy B knight

The first possiblity is consistant. The second would isn't because B would be a knight who was lying.


 * So A = knight
 * B = spy
 * C =knave

is the only consistant solution Theresa knott 10:08, 6 Oct 2003 (UTC)


 * Excellent, Theresa! Couldn't have said it better... Thomas

Hope this is the place for question : in the consistant solution, the spy (B) is not lying anymore !