What does it mean that Chen Shizhao was deceived and didn't know it?

Being deceived without knowing it (classified as ancient jokes)

Li Xiya Yao (yāo), a writer in Ming Dynasty, and Chen Shizhao were playing dice together, and he deliberately wanted to tease Chen Shizhao, who was in a trance.

Li Xiya saw that the front of the dice was right, so he mysteriously pointed to Chen Shizhao and said, "I guess the bottom of the dice must be

six." Open it, and sure enough, the bottom is six. In this way, Li Xiya guessed correctly several times in a row. Chen Shizhao was so surprised

that he said to everyone, "Li Xiya is really a genius." Someone told him, "What is it on the top of the dice and six on the bottom? This < P > is a fixed number. What's strange?" Chen Shizhao said, "If that's the case, I can guess correctly." So he went to see Li Xiya specially.

Li Xiya had long expected that Chen Shizhao would definitely come again, so he found another dice in advance to confuse the original figures

. Chen Shizhao guessed several times in succession according to the number of people who told him to go up and down, but he didn't guess once. He

praised Li Xiya and said, "You are amazing! I knew you wouldn't cheat me. "