一個哲學悖論問題
you are visiting a foreign country inhabited only by knaves and knights;knaves always lie and knights tell the truth,you come to a fork in the road,where one branch leads to the capital and other does not.an inhabitant,kitty,is passing by,and will answer any question with "yes"or "no",but you can just ask one question.what one yes-or-no question you should ask kitty to determine which branch leads to the capital?
意思就是
就是你去一個國家,這個國家就只住著狡猾的人和騎士,狡猾的人專門說謊,騎士通常是講真話.你到了一個分叉路口,一邊是通往這個國家的首都,一邊不是.你碰到一個路人,你可以問她任何一個用yes或no回答的問題（只能問一個）.
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