 Whereas the Shuogua authors focus on the 8 trigrams, the Xugua authors pay special attention to the sequence of the 64 hexagrams (for a full translation of Xugua, see Lynn 1994: 103–110). In rationalizing the hexagram sequences, the Xugua authors match the order of hexagrams with key moments of human evolution, beginning with the construction of a primitive community to the establishment of a patrilineal family structure based on gender distinctions and matrimony. Later, the patrilineal family structure is further expanded into a complex socio-political system based on the distinctions between kings and officials, and rulers and ruled. While this process of development seems inevitable, occasionally the Xugua authors call attention to challenges and obstacles in maintaining a stable community. They identify moments where the socio-political order is corrupt (Kui #38 and Jian #39) or disintegrated (Huan #59). Because of the danger of corruption and disintegration, the Xugua authors emphasize the need for renewing the socio-political order by replacing corrupt leaders (Ge #49) and re-structuring the entire system (Ding #50). Nevertheless, occasional interruptions do not interfere with or slow down the steady progress of humankind. Based on this epic saga, the Xugua authors place the fortune and misfortune of individuals in the longue durée of human evolution. Accidents, irritant behaviors, unexpected occurrences, and unplanned actions are absorbed and rationalized in the onward march of humankind.