That is to accept the destiny. An old formula for praising emperors. First seen in "Selected Works". "Book for Shi Zhongrong and Sun Hao" written by Sun Chu of the Jin Dynasty: "Taizu carries the fortune, and Shenwu responds."
In the past, the emperor issued an edict, and the first sentence was "I carry it with heaven, the emperor's edict said." "Fengtian" means that becoming the emperor is the entrustment of the Emperor of Heaven. The meaning of "carrying" is accurately stated in ancient books such as "Hanshu Jiaosi Zhi". The ancients believed that all things in the world are composed of gold, wood, water, fire and earth, which are called the "Five Elements". They move, die and grow according to certain rules, which are called the "Five Movements". During the Warring States Period, Zou Yan, a native of Qi, called the "Five Lucks" the "Five Virtues", which were linked to the rule of emperors and the rise and fall of world affairs. According to the law of "the victory of the Five Lucks", the right to rule was confirmed to be reasonable and legal. According to Zou Yan's statement, Qin Shihuang believed that the Zhou Dynasty had the virtue of fire and that water could defeat fire, which confirmed that Qin had the virtue of water. In the Han Dynasty, it was changed to Tu De, which means that soil is better than water. In the late Western Han Dynasty, scholars Liu Xiang and Liu Xin and their son proposed a new theory, believing that the basis of the Five Movements for the transfer of imperial power was not mutual victory, but mutual inheritance. Starting from Fuxi, the virtue of wood is considered, and the turn of the Qin Dynasty is also the virtue of wood. Wood can make fire, and fire carries the luck of wood. The virtue of fire should be in the Han Dynasty. This statement was recognized by Liu Xiu, the founder of the Eastern Han Dynasty, which is the origin of the titles "Yan Han" and "Yan Liu".
From then on, Cao Pi used earth to carry fire, Sima Yan used gold to carry earth, and Liu Yu used water to carry gold. Every time there was a change of dynasty, the legacy would continue until the monarchy was overthrown, and then the legacy would no longer exist.