“Zhuangzi · Qi Wu Lun" said: "in the past, Zhuang Zhou dream was Hu Die, lifelike Hu Die, self metaphor of ambition and! I don“t know Zhou. Suddenly, you will feel like you are in the Zhou Dynasty. I don“t know that Zhou“s dream is Hu diehe, and Hu Die“s dream is Zhou he? Zhou and Hu Die must be divided. This is called materialization. "