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, Scarlett, Ella, Daniel, Amelia, and Aurora. Victoria said that Scarlett is a knight. Scarlett said, "Ella is a knave." "Amelia is a knave" - Ella. Daniel commented, "Aurora is a knave if and only if Victoria is a knave". Amelia expressed that Scarlett is a knave if and only if Victoria is a knight. Aurora told you that Victoria is a knight and Ella is a knave. So who is a knight and who is a knave?
Victoria is a knave, Scarlett is a knave, Ella is a knight, Daniel is a knight, Amelia is a knave, and Aurora is a knave.
(1) Victoria is a knave
(2) Scarlett is a knave
(3) Ella is a knight
(4) Daniel is a knight
(5) Amelia is a knave
(6) Aurora is a knave
Assume Victoria is a knight. No contradiction is found in their claim that Scarlett is a knight. Assume Scarlett is a knight. No contradiction is found in their claim that Ella is a knave. Ella cannot be a knight, because this would contradict the claim of Scarlett that Ella is a knave. Assume Ella is a knave. No contradiction is found in their false claim that Amelia is a knave. Amelia cannot be a knight, because this would contradict the claim of their own that Scarlett is a knave if and only if Victoria is a knight. Amelia cannot be a knave, because this would contradict the false claim of Ella that Amelia is a knave. We have exhausted all possibilities for Amelia and Ella, so let us go back and reconsider Scarlett. Scarlett cannot be a knave, because this would contradict the claim of Victoria that Scarlett is a knight. We have exhausted all possibilities for Scarlett, so let us go back and reconsider Victoria. Assume Victoria is a knave. No contradiction is found in their false claim that Scarlett is a knight. Scarlett cannot be a knight, because this would contradict the false claim of Victoria that Scarlett is a knight. Assume Scarlett is a knave. No contradiction is found in their false claim that Ella is a knave. Assume Ella is a knight. No contradiction is found in their claim that Amelia is a knave. Amelia cannot be a knight, because this would contradict the claim of Ella that Amelia is a knave. Assume Amelia is a knave. No contradiction is found in their false claim that Scarlett is a knave if and only if Victoria is a knight. Assume Daniel is a knight. No contradiction is found in their claim that Aurora is a knave if and only if Victoria is a knave. Aurora cannot be a knight, because this would contradict the claim of Daniel that Aurora is a knave if and only if Victoria is a knave. Assume Aurora is a knave. No contradiction is found in their false claim that Victoria is a knight and Ella is a knave.