81450
These traditions can be summarized as : fengshui geomancy and astronomy ; the well-field system ; gaitian cosmology ; qi as a medium of energy connecting man , earth , and heaven ; political power shared between a military aristocracy and educated advisers ; the holy place bo ; a three-tiered economic system under absolute state control ; early writing ; and the walled yet portable capital city as a diagram of political power .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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