Send your enemy beautiful women to cause discord within his camp. This strategy can work on three levels. First, the ruler becomes so enamored with the beauty that he neglects his duties and allows his vigilance to wane. Second, other males at court will begin to display aggressive behavior that inflames minor differences hindering co-operation and destroying morale. Third, other females at court, motivated by jealousy and envy, begin to plot intrigues further exasperating the situation.
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Even though this has been done many times, perhaps the most famous historical example is Xi Shi who was sent to the State of Wu during the Spring and Autumn Period.
Xi Shi's beauty was said to be so extreme that while laundering her garments in the river, the fish were so dazzled that they forgot how to swim and gradually sunk to the bottom of the rive.
King Gou Jian of Yue, was once imprisoned after a defeat in a war by King Fu Chai of Wu, king of the State of Wu. The state of Yue later became a tribulatory to Wu. Secretly planning his revenge, Gou Jian's minister Wen Zhong suggested training beautiful women and offering them to Fu Chai as a tribute. His other minister, Fan Li, found Xi Shi and Zheng Dan, and gifted them to Fu Chai in 490 BC.
Bewitched by the beauty of Xi Shi and Zheng Dan, Fu Chai forgot all about his state affairs and on their instigation, killed his best advisor, the great general Wu Zixu. Fu Chai even built Guanwa Palace (Palace of Beautiful Women) in an imperial park on the slope of Lingyan Hill, about 15 kilometers west of Suzhou. The strength of Wu dwindled, and in 473 BC Gou Jian launched his strike and put the Wu army to full rout. King Fu Chai lamented that he should have listened to Wu Zixu, and then committed suicide.