But the "door" on the plaque of the Forbidden City is not linked, and there are many historical allusions. According to Jo Yeo-jeong at the end of the Qing Dynasty and the beginning of the Republic of China, most of the inscriptions on the doors in the Qing Dynasty were without hooks, including the Forbidden City and folk plaques. Nowadays, many plaques of ancient buildings have begun to be hooked up, mainly because these buildings were rebuilt later and the characters were written by modern people. At that time, people generally didn't take the bait, which may be a custom at that time.
Of course there are legends. It is said that during the Southern Song Dynasty, the palace caught fire. After investigation by the other party, no cause of the fire was found. At that time, Emperor Zhao Gou interrogated the eunuch on duty at that time, and the eunuch was afraid of taking the blame. He casually said that the cause of the fire was the word "fire hook" on the door, and the inscription "vertical hook" on the door really lit a fire like a pillar of fire. Zhao Gou was superstitious too, so he ordered all the hook paintings on the door to be removed.
This statement continued until the Ming dynasty, and Zhu Yuanzhang of the Ming dynasty also had his own views. He thought that the hook on the door was unlucky, the hook painting was sharp, and it was easy to trip, which hindered outstanding talents from entering the palace, so he removed all the hook paintings on the palace. Emperor Qianlong of the Qing Dynasty thought that the hook on the door was easy to scratch his dragon Lin, and that he was the real dragon emperor, and he was not allowed to hook the inscription on the door. In this way, the legends of these palaces gradually spread to the people, and the folk inscriptions slowly began to take off the hooks, but now most of us don't believe this and put the hooks back.