A very special island is inhabited only by knights and knaves. Knights always tell the truth, and knaves always lie. You meet 6 inhabitants: Joseph, Isabella, Amelia, Victoria, Noah, and Mason. Joseph told you that Amelia is a knight if and only if Isabella is a knave. Isabella said that Noah is a knave and Isabella is a knight. Amelia expressed that Noah is a knave if and only if Isabella is a knight. "Amelia is a knave," Victoria mentioned. "If Mason is a knight then Victoria is a knave" - Noah. Mason asserted: "If Mason is a knight then Joseph is a knight". So who is a knight and who is a knave?
Joseph is a knight, Isabella is a knave, Amelia is a knight, Victoria is a knave, Noah is a knight, and Mason is a knight.
(1) Joseph is a knight
(2) Isabella is a knave
(3) Amelia is a knight
(4) Victoria is a knave
(5) Noah is a knight
(6) Mason is a knight
Assume Joseph is a knight. No contradiction is found in their claim that Amelia is a knight if and only if Isabella is a knave. Assume Amelia is a knight. No contradiction is found in their claim that Noah is a knave if and only if Isabella is a knight. Assume Noah is a knight. No contradiction is found in their claim that If Mason is a knight then Victoria is a knave. Assume Mason is a knight. No contradiction is found in their claim that If Mason is a knight then Joseph is a knight. Victoria cannot be a knight, because this would contradict the claim of their own that Amelia is a knave. Assume Victoria is a knave. No contradiction is found in their false claim that Amelia is a knave. Isabella cannot be a knight, because this would contradict the claim of Joseph that Amelia is a knight if and only if Isabella is a knave. Assume Isabella is a knave. No contradiction is found in their false claim that Noah is a knave and Isabella is a knight.