A very special island is inhabited only by knights and knaves. Knights always tell the truth, and knaves always lie. You meet 6 inhabitants: Grace, Noah, Charlotte, Aurora, Isabella, and Luke. Grace expressed that Charlotte is a knave and Aurora is a knight. "Grace is a knight and Grace is a knave," Noah declared. "Aurora is a knave or Luke is a knight," Charlotte claimed. Aurora expressed that Charlotte is a knave or Isabella is a knight. "Noah is a knave," Isabella declared. "Isabella is a knight" - Luke. So who is a knight and who is a knave?
Grace is a knave, Noah is a knave, Charlotte is a knight, Aurora is a knight, Isabella is a knight, and Luke is a knight.
(1) Grace is a knave
(2) Noah is a knave
(3) Charlotte is a knight
(4) Aurora is a knight
(5) Isabella is a knight
(6) Luke is a knight
Assume Grace is a knight. No contradiction is found in their claim that Charlotte is a knave and Aurora is a knight. Charlotte cannot be a knight, because this would contradict the claim of Grace that Charlotte is a knave and Aurora is a knight. Assume Charlotte is a knave. No contradiction is found in their false claim that Aurora is a knave or Luke is a knight. Assume Aurora is a knight. No contradiction is found in their claim that Charlotte is a knave or Isabella is a knight. Assume Isabella is a knight. No contradiction is found in their claim that Noah is a knave. Noah cannot be a knight, because this would contradict the claim of their own that Grace is a knight and Grace is a knave. Assume Noah is a knave. No contradiction is found in their false claim that Grace is a knight and Grace is a knave. Luke cannot be a knight, because this would contradict the false claim of Charlotte that Aurora is a knave or Luke is a knight. Luke cannot be a knave, because this would contradict the false claim of their own that Isabella is a knight. We have exhausted all possibilities for Luke and Noah, so let us go back and reconsider Isabella. Assume Isabella is a knave. No contradiction is found in their false claim that Noah is a knave. Noah cannot be a knight, because this would contradict the claim of their own that Grace is a knight and Grace is a knave. Noah cannot be a knave, because this would contradict the false claim of Isabella that Noah is a knave. We have exhausted all possibilities for Noah and Isabella, so let us go back and reconsider Aurora. Aurora cannot be a knave, because this would contradict the claim of Grace that Charlotte is a knave and Aurora is a knight. We have exhausted all possibilities for Aurora and Charlotte, so let us go back and reconsider Grace. Assume Grace is a knave. No contradiction is found in their false claim that Charlotte is a knave and Aurora is a knight. Assume Charlotte is a knight. No contradiction is found in their claim that Aurora is a knave or Luke is a knight. Assume Aurora is a knight. No contradiction is found in their claim that Charlotte is a knave or Isabella is a knight. Assume Isabella is a knight. No contradiction is found in their claim that Noah is a knave. Noah cannot be a knight, because this would contradict the claim of their own that Grace is a knight and Grace is a knave. Assume Noah is a knave. No contradiction is found in their false claim that Grace is a knight and Grace is a knave. Assume Luke is a knight. No contradiction is found in their claim that Isabella is a knight.