A very special island is inhabited only by knights and knaves. Knights always tell the truth, and knaves always lie. You meet 6 inhabitants: Jackson, Zoey, Emily, Penelope, Charlotte, and Samuel. "Penelope is not a knight" - Jackson. Zoey asserted: "Emily is a knave". According to Emily, "Penelope is a knight". Penelope told you that Jackson is a knave or Charlotte is a knave. Charlotte stated, "Jackson is a knight if and only if Emily is a knight". Samuel said, "Jackson is a knight." So who is a knight and who is a knave?
Jackson is a knave, Zoey is a knave, Emily is a knight, Penelope is a knight, Charlotte is a knave, and Samuel is a knave.
(1) Jackson is a knave
(2) Zoey is a knave
(3) Emily is a knight
(4) Penelope is a knight
(5) Charlotte is a knave
(6) Samuel is a knave
Assume Jackson is a knight. No contradiction is found in their claim that Penelope is not a knight. Penelope cannot be a knight, because this would contradict the claim of Jackson that Penelope is not a knight. Assume Penelope is a knave. No contradiction is found in their false claim that Jackson is a knave or Charlotte is a knave. Assume Charlotte is a knight. No contradiction is found in their claim that Jackson is a knight if and only if Emily is a knight. Emily cannot be a knight, because this would contradict the claim of their own that Penelope is a knight. Emily cannot be a knave, because this would contradict the claim of Charlotte that Jackson is a knight if and only if Emily is a knight. We have exhausted all possibilities for Emily, so let us go back and reconsider Charlotte. Charlotte cannot be a knave, because this would contradict the false claim of Penelope that Jackson is a knave or Charlotte is a knave. We have exhausted all possibilities for Charlotte and Penelope, so let us go back and reconsider Jackson. Assume Jackson is a knave. No contradiction is found in their false claim that Penelope is not a knight. Assume Penelope is a knight. No contradiction is found in their claim that Jackson is a knave or Charlotte is a knave. Assume Charlotte is a knight. No contradiction is found in their claim that Jackson is a knight if and only if Emily is a knight. Emily cannot be a knight, because this would contradict the claim of Charlotte that Jackson is a knight if and only if Emily is a knight. Emily cannot be a knave, because this would contradict the false claim of their own that Penelope is a knight. We have exhausted all possibilities for Emily, so let us go back and reconsider Charlotte. Assume Charlotte is a knave. No contradiction is found in their false claim that Jackson is a knight if and only if Emily is a knight. Assume Emily is a knight. No contradiction is found in their claim that Penelope is a knight. Zoey cannot be a knight, because this would contradict the claim of their own that Emily is a knave. Assume Zoey is a knave. No contradiction is found in their false claim that Emily is a knave. Samuel cannot be a knight, because this would contradict the claim of their own that Jackson is a knight. Assume Samuel is a knave. No contradiction is found in their false claim that Jackson is a knight.