To understand an opponent's arguments or methods deeply and then use their own points to refute them; to turn an adversary's words or logic against them.
Era:
Ancient
Frequency:
Story:
During the Eastern Han Dynasty, Zheng Xuan studied under Kong Rong, who held him in high regard and praised him for truly grasping his scholarship.
Zheng Xuan wrote critiques titled "Mo Shou" and "Fei Ji," specifically targeting scholar He Xiu's works, such as "Gongyang Mo Shou" and "Zuoshi Gaohuang." In his writings, Zheng Xuan effectively pinpointed the weaknesses and inconsistencies within He Xiu's own arguments.
Upon reading Zheng Xuan's critiques, He Xiu sighed in admiration, saying, "Zheng Xuan has entered my house and taken up my own spear to fight me!" This idiom later came to describe using an opponent's own reasoning or methods to defeat them.