There are different opinions on who Mu Zhi is in the "Dragon and Tiger Announcement" of the imperial examination in the 8th year of Zhenyuan period ( 792 ) since the emergence of the revised edition of  Wenyuan Yinghua  in the Southern Song Dynasty, which was recorded in the literature of  Deng Ke Ji Kao  and  Supplements to Deng ke ji kao  Through the investigation of Mu Zhi and the Henan Mu surname in the middle Tang Dynasty in the time of Successful Candidates in Imperial Exams,the official experience, the brothers ranking order, and the standardization of the name, it is believed that Mu Zhi, who Being Admitted to Successful Candidates in Imperial Exams in the 8th year of  Zhenyuan period ( 792 ), was the son of Mu Shen, the nephew of Mu Ning, and the brother of Mu Zan, Mu Zhi, Mu Yuan, and Mu Shang. He was the father of Mu Renyu, the Military Governor of Xuanwujun during the reign of Xizong, and had been a councilor of the Ministry of War in feudal China. Based on this, the author of  Quan Tang Wen  and A letter to the monk Yan Fan should be Mu Zhi rather than Mu Zhi.