A very special island is inhabited only by knights and knaves. Knights always tell the truth, and knaves always lie. You meet 6 inhabitants: Ava, David, Sophia, Aurora, Amelia, and Scarlett. "David is a knave or Scarlett is a knight," Ava mentioned. David expressed that If David is a knight then Amelia is a knight. Sophia was heard saying, "Scarlett is not a knave". Aurora stated, "Ava is a knave and Scarlett is a knave". "Sophia is a knight," Amelia claimed. Scarlett noted, "If Sophia is a knave then Ava is a knight". So who is a knight and who is a knave?
Ava is a knight, David is a knight, Sophia is a knight, Aurora is a knave, Amelia is a knight, and Scarlett is a knight.
(1) Ava is a knight
(2) David is a knight
(3) Sophia is a knight
(4) Aurora is a knave
(5) Amelia is a knight
(6) Scarlett is a knight
Assume Ava is a knight. No contradiction is found in their claim that David is a knave or Scarlett is a knight. Assume David is a knight. No contradiction is found in their claim that If David is a knight then Amelia is a knight. Assume Amelia is a knight. No contradiction is found in their claim that Sophia is a knight. Assume Sophia is a knight. No contradiction is found in their claim that Scarlett is not a knave. Assume Scarlett is a knight. No contradiction is found in their claim that If Sophia is a knave then Ava is a knight. Aurora cannot be a knight, because this would contradict the claim of their own that Ava is a knave and Scarlett is a knave. Assume Aurora is a knave. No contradiction is found in their false claim that Ava is a knave and Scarlett is a knave.