A very special island is inhabited only by knights and knaves. Knights always tell the truth, and knaves always lie. You meet 6 inhabitants: Liam, Evelyn, Isabella, Jackson, Aiden, and Sofia. Liam expressed that Evelyn is a knight. Evelyn remarked, "Evelyn is a knight and Isabella is a knave". As Isabella put it, "If Sofia is a knave then Liam is a knight". As Jackson put it, "Evelyn is a knave and Sofia is a knight". In Aiden's words: "Jackson is a knave and Evelyn is a knight". "If Liam is a knight then Jackson is a knight" - Sofia. So who is a knight and who is a knave?
Liam is a knave, Evelyn is a knave, Isabella is a knight, Jackson is a knight, Aiden is a knave, and Sofia is a knight.
(1) Liam is a knave
(2) Evelyn is a knave
(3) Isabella is a knight
(4) Jackson is a knight
(5) Aiden is a knave
(6) Sofia is a knight
Assume Liam is a knight. No contradiction is found in their claim that Evelyn is a knight. Assume Evelyn is a knight. No contradiction is found in their claim that Evelyn is a knight and Isabella is a knave. Isabella cannot be a knight, because this would contradict the claim of Evelyn that Evelyn is a knight and Isabella is a knave. Isabella cannot be a knave, because this would contradict the false claim of their own that If Sofia is a knave then Liam is a knight. We have exhausted all possibilities for Isabella, so let us go back and reconsider Evelyn. Evelyn cannot be a knave, because this would contradict the claim of Liam that Evelyn is a knight. We have exhausted all possibilities for Evelyn, so let us go back and reconsider Liam. Assume Liam is a knave. No contradiction is found in their false claim that Evelyn is a knight. Evelyn cannot be a knight, because this would contradict the false claim of Liam that Evelyn is a knight. Assume Evelyn is a knave. No contradiction is found in their false claim that Evelyn is a knight and Isabella is a knave. Assume Isabella is a knight. No contradiction is found in their claim that If Sofia is a knave then Liam is a knight. Assume Sofia is a knight. No contradiction is found in their claim that If Liam is a knight then Jackson is a knight. Assume Jackson is a knight. No contradiction is found in their claim that Evelyn is a knave and Sofia is a knight. Aiden cannot be a knight, because this would contradict the claim of their own that Jackson is a knave and Evelyn is a knight. Assume Aiden is a knave. No contradiction is found in their false claim that Jackson is a knave and Evelyn is a knight.