Does the nature have no origin? I cannot tell. Have human beings had any incipient stage of their own? I cannot tell, either. Nevertheless, has any incipient stage ever existed? I think there has been, which is closer to the fact. But how could we prove it? We can prove it through the system of feudalism. The system had existed throughout sagacious kings of Yao, Shun, Yu, Tang, Wen, Wu, and no one could ever abolish it. They wanted to, but why could not they? Because the trend of social development could not allow them to do so. Maybe such a trend is the true situation human beings had to accommodate themselves in the incipient stage. Therefore, fedualism and incipient stage had been highly correlated, and it might not be the oringinal idea of those sagacious kings.
In that incipient stage, human beings were coexisting with all creatures: sprawling weeds and trees, scrambling reptiles and beasts. But human beings boast of no feathers to keep themselves warm, nor of no adequate stuff to feed and protect themselves. Xun Zi once said, "People have to fully captalize things from outside so as to survive." Thus, people have to compete among one another, incessantly vying for things for themselves. Therefore, they must find someone who can make judicious decision for them to follow suit. The wise man, who is sagacious and discerning, is able to persuade a lot of believers to follow him. But if people do not listen to him and continue to fight with each other, he has to punish them and fill them with awe. In so doing, the system of hierarchy, criminal law, and decree are thus introduced. Hence, people of close interests gather into groups, so struggles between the different groups will exacerbate. When the struggles become larger, it necessitate army and leader of stature. Thus, a leader of greater stature emerges and makes other smaller leaders to under his command. In order to appease those smaller leaders and let them better manage their people, the leader of greater stature recognizes them as vassals with enfeoffment as under a fedual-like system. As the struggles between the vassals arise again, it takes an even stronger leader to let the larger vassals such as Bo and Shuai follow his order until the entire tribes are united and all listen to only one supreme leader. That has been the complicated process that a hierarchical system is so founded: from managerials of low level, to vassals, to Bo and Shuai, until to the supreme leader, the king. As all leaders of all levels, from the bottom to the top, are persons of stature, so after their death, people are prone in accepting the decendants of the deceased leaders and continue to pay allegiance to them. Therefore the feudal system is not necessarily the idea out of sages; instead, it has been a social trend.
Things pertaining to the eras of Yao, Shun, Yu, and Tang has been long gone, but the records of Zhou Dynasty are well documented. When Zhou ruled the whole country, it divided the land into many parts under five categories and gave each one an enfeoffment. The vassals, dispersed in the earth like constellations in the skies, surrounded the House of Zhou like a wheel to a spoke. When they gathered they paid an audience with the King, and after that they were the subjects guarding the land for the King. However, when in the time of King Yi, he broke the rule and etiquette by condescending himself to come down the palace to meet his vassals. Although later King Xuan brought stature again to the House by gaining several victories all over the country, still he was unable to determine the heir of earl in Lu. The prestige of the House thus gradually declined through King You and King Li till the House moved to the new capital in east. Then the status of House of Zhou had downgraded to the level equivalent to a vassal. Later on, things of insubordination ensued, such as questioning the weight of royal emblem: Ding, injuring King by shooting his shouder, attacking one of Kings major subordinate and forcing the King to execute another, and so on. Thus, the whole country was in disorder, the hierachical relation between king and the vassals had broken. I think the House of Zhou had long lost its authority to control the country, and King of Zhou had become nothing but a figurehead on top of vassals. Was it the result like an animal having too large a tail to wiggle at last? The real ruling power thus was divided and distributed to twelve powerful vassals, and final to Big Seven through annexation. In nutshell, at first the ruling power inappropriately delegated to vassals, and eventually was taken all away by newly-emerging Qin. That was the root cause of failure and fall of Zhou Dynasty.
So Qin Dynasty was founded. The new emperor replaced the vassal states with counties and dispatched governors and magistrates to rule the country on behalf of the royal house. The capital of the empire was best strategically located upstream of Yellow River, which was capable of controlling all the country in its hands. Qin just did a right and great thing. However, ere long the whole empire collapsed due to its oppression and tyranny: excessively labor conscription, extremely draconian punishment, and totally unrestrained outlays. With tacit understanding, those oppressed outlaws carrying hoes and sticks who were sent to frontiers easily united in drones in uprising against Qin. There were civilian rebels, but none from officials. People harbor rancor against Qin Empire, but officials dared not disobey the emperor. So rebellion raised from bottom and swiftly spread; officials were killed everywhere. Thus, the root cause was the deep grudge from people against Qin Empire, not because of its governmental system of county and district.
Han Dynasty established. The newly-founded dynasty rectified the drawback of delegating systems by restoring the feudalism of Zhou. So Han distributed the lands to the members of its royal family and the subjects having great deeds. But before long several fedual states rebelled and the central government was exhausted in oppressing the tumults, which resulted in the first emperor was besieged by Huns and injured by arrow. The ill had lasted for three generations uncured until some capable subjects mapped out a smart scheme to debilitate the power of fedual states and transferred it to the officials dispatched from central government. Actually at the very begining of Han Dynasty, feudal system and county system were coexisted, and there had been rebellions from feudal states, but none from counties. Therefore, the advantange of county system of Qin is quite obvious, and it can be testified throughout hundreds of generation after Han.
When Tang Dynasty began, local administrations, such as Zhou and Xian, were well and effectively. The ones who wrought havoc to the country were local warlords, not officials of Zhou and Xian. So it was warlords, not officials of Zhou and Xian, who brought the havoc. Though there were shrewd and atrocious insurgents who sometimes rebelled throughout Tang era, none of the rebellions was from central-controlled local governments. Therefore, the establishment of Zhou and Xian by central government is irreplaceable.