A very special island is inhabited only by knights and knaves. Knights always tell the truth, and knaves always lie. You meet 6 inhabitants: Victoria, Emma, Evelyn, Daniel, Noah, and Ella. In a statement by Victoria: "Ella is not a knight". Emma said that Victoria is a knave and Daniel is a knight. "Victoria is a knight if and only if Emma is a knave," Evelyn mentioned. "Noah is a knight if and only if Victoria is a knave," Daniel declared. Noah was heard saying, "If Emma is a knave then Evelyn is a knight". Ella said that If Noah is a knave then Noah is a knight. So who is a knight and who is a knave?
Victoria is a knave, Emma is a knight, Evelyn is a knight, Daniel is a knight, Noah is a knight, and Ella is a knight.
(1) Victoria is a knave
(2) Emma is a knight
(3) Evelyn is a knight
(4) Daniel is a knight
(5) Noah is a knight
(6) Ella is a knight
Assume Victoria is a knight. No contradiction is found in their claim that Ella is not a knight. Ella cannot be a knight, because this would contradict the claim of Victoria that Ella is not a knight. Assume Ella is a knave. No contradiction is found in their false claim that If Noah is a knave then Noah is a knight. Noah cannot be a knight, because this would contradict the false claim of Ella that If Noah is a knave then Noah is a knight. Assume Noah is a knave. No contradiction is found in their false claim that If Emma is a knave then Evelyn is a knight. Emma cannot be a knight, because this would contradict the claim of their own that Victoria is a knave and Daniel is a knight. Assume Emma is a knave. No contradiction is found in their false claim that Victoria is a knave and Daniel is a knight. Assume Daniel is a knight. No contradiction is found in their claim that Noah is a knight if and only if Victoria is a knave. Evelyn cannot be a knight, because this would contradict the false claim of Noah that If Emma is a knave then Evelyn is a knight. Evelyn cannot be a knave, because this would contradict the false claim of their own that Victoria is a knight if and only if Emma is a knave. We have exhausted all possibilities for Evelyn, so let us go back and reconsider Daniel. Daniel cannot be a knave, because this would contradict the false claim of their own that Noah is a knight if and only if Victoria is a knave. We have exhausted all possibilities for Daniel, Emma, Noah, and Ella, so let us go back and reconsider Victoria. Assume Victoria is a knave. No contradiction is found in their false claim that Ella is not a knight. Assume Ella is a knight. No contradiction is found in their claim that If Noah is a knave then Noah is a knight. Assume Noah is a knight. No contradiction is found in their claim that If Emma is a knave then Evelyn is a knight. Assume Emma is a knight. No contradiction is found in their claim that Victoria is a knave and Daniel is a knight. Assume Daniel is a knight. No contradiction is found in their claim that Noah is a knight if and only if Victoria is a knave. Assume Evelyn is a knight. No contradiction is found in their claim that Victoria is a knight if and only if Emma is a knave.