A very special island is inhabited only by knights and knaves. Knights always tell the truth, and knaves always lie. You meet 6 inhabitants: Chloe, Jack, Avery, Michael, Sebastian, and Elizabeth. "Elizabeth is not a knight" - Chloe. Jack stated, "Sebastian is a knight if and only if Elizabeth is a knight". Avery was heard saying, "Avery is a knight and Sebastian is a knave". In Michael's words: "Jack is not a knave". Sebastian was heard saying, "Jack is a knave". Elizabeth noted, "Sebastian is not a knight". So who is a knight and who is a knave?
Chloe is a knight, Jack is a knave, Avery is a knave, Michael is a knave, Sebastian is a knight, and Elizabeth is a knave.
(1) Chloe is a knight
(2) Jack is a knave
(3) Avery is a knave
(4) Michael is a knave
(5) Sebastian is a knight
(6) Elizabeth is a knave
Assume Chloe is a knight. No contradiction is found in their claim that Elizabeth is not a knight. Elizabeth cannot be a knight, because this would contradict the claim of Chloe that Elizabeth is not a knight. Assume Elizabeth is a knave. No contradiction is found in their false claim that Sebastian is not a knight. Assume Sebastian is a knight. No contradiction is found in their claim that Jack is a knave. Jack cannot be a knight, because this would contradict the claim of their own that Sebastian is a knight if and only if Elizabeth is a knight. Assume Jack is a knave. No contradiction is found in their false claim that Sebastian is a knight if and only if Elizabeth is a knight. Avery cannot be a knight, because this would contradict the claim of their own that Avery is a knight and Sebastian is a knave. Assume Avery is a knave. No contradiction is found in their false claim that Avery is a knight and Sebastian is a knave. Michael cannot be a knight, because this would contradict the claim of their own that Jack is not a knave. Assume Michael is a knave. No contradiction is found in their false claim that Jack is not a knave.