Four inhabitants of the island make the statements as given below. Each of these inhabitants are either Liars or Knights. Little is known regarding the identity of the four inhabitants except for the fact that Q and R are not both Knights.

P's Statement: If asked, Q would say that he and S belong to the same group.

Q's Statement: If asked, S would say that he and P do not belong to the same group.

R's Statement: P and myself belong to the same group..

S's Statement: If asked, P would say that he and R do not belong to the same group.

To what group or groups do the four speakers belong?

(In reply to Q's and R's by Allen)

Actually, the only thing that doesn't work about that solution is P's statement. Since P is a knight, his statement must be true, assuming he would state that S and himself were in the same group. They ARE in fact in the same group, but Q would not say that because he is a liar.

Posted by Stefanie on 2006-08-18 09:20:53