First of all, it has great affinity with the centralized political system, and it is highly adapted to the need to continuously strengthen centralization after the maturity of China feudal society. As we all know, there is a very obvious difference between the imperial examination system and the military, supervision and dismissal systems implemented before Sui and Tang Dynasties, that is, the top-down way of the imperial examination system. The implementation of the military service system depends on the bottom-up military service evaluation report; The implementation of the inspection system depends on bottom-up recommendation; To implement the exclusion system is to directly hand over the right to use human rights to the following people. However, the imperial examination system is very different. Its standards are completely decided by the central government, and the selection of personnel is completely decided by the central government. This is a top-down way of selecting officials. The autonomy of local personnel was completely deprived by the imperial examination presided over by the central government.
Of course, the imperial examination system is also bottom-up in concrete implementation. In the Tang Dynasty, the imperial examination was first "rural tribute" and then "rural examination"; Until the Ming and Qing dynasties, it was also the first time that there was a post-exam, and then there was a post-exam. However, this kind of down-first-up is only a matter of order, not a bottom-up problem of the initiative in selecting officials. The "rural tribute" in the Tang Dynasty is completely different from the recommendation under the inspection system, and it is even different from the self-appointment and dismissal under the recall system. Local officials only obey orders and conduct pre-selection according to the specific criteria for selecting officials stipulated by the central government. In contrast, the procuratorial system and banishment system implemented in Han Dynasty obviously deviated from centralization. Under the system of inspection and dismissal, even if the central government has regulations on the employment standards, the right of interpretation is in the hands of local promoters. In the legal sense, whoever has the power of legal interpretation will have the legislative power in the practical sense. Therefore, after the establishment of the centralized autocratic rule system in the Han Dynasty, the power of employing people fell into the hands of local officials through inspection and recall. The emergence of the local separatist regime at the end of Han Dynasty was closely related to the procuratorial system and the local power groups with "students all over the world" created by the purge. Historians of later generations believe that the censorship resulted in the patriarchal and personal attachment relationship between local governors and subordinate officials, and "each flatters his master and does not know that there is a son of heaven" (Wang Fuzhi: reading is like a mirror). The imperial examination system does not need the explanation of local officials at all, so there is no human rights of local officials. After the establishment of the imperial examination system, the spirit of centralization has been thoroughly reflected. Under the imperial examination system, local "rural tribute" and "jurors" will not think that their "tribute" and "jurors" are due to the kindness of a local official. More importantly, even if a scholar has won the title of "rural tribute" or a first-class fame, he must pass the national unified examination before deciding on the choice. In this way, the power of selecting local officials was completely deprived by the imperial examination system, and the way of producing officials also met the requirements of centralization. It is impossible to create local forces that hinder centralization by selecting officials. It is precisely because the imperial examination system is highly adapted to the need of strengthening centralization that it has been highly valued by rulers since Sui and Tang Dynasties. At the beginning of the imperial examination system, Li Shimin once had a famous saying. He watched the new Jinshi file in from the door and proudly said, "The hero of the world is in my life!" " "Obviously, in Li Shimin's eyes, he not only saw that the new Jinshi was a talent, but also saw that the original" each in his own right "was unified to the central government!