Zheng-tong: Year 5, Month 5, Day 15
14 Jun 1440
Imperial orders of instruction were sent to the Yun-nan Regional Commander and Vice Commissioner-in-Chief Mu Ang. The orders read: "In the past, for my forbears, your father the Qian-ning Zhao-jing Prince defended Yun-nan and kept the area pacified and soothed. The man and the yi were submissive and the border regions were at peace. The Court came to trust that there would be no troubles in the South-west. Your elder brother continued the tradition and he was also able to maintain peace there. All of this you know. Recently, Si Ren-fa attacked and plundered neighbouring territories. You followed the way of restraining and ruling through soothing and comforting. However, he became increasingly wild and violent. You thus repeatedly requested permission to despatch troops to punish him. Knowing that you must have made good plans and appropriate arrangements, I ordered you to take on the post of regional commander and to lead 100,000 troops, and expected that you could achieve success. I did not expect that you would be fearful and passive and would lose control of the troops. In employing troops, speed is of the utmost importance. From Yun-nan to Lu-chuan is not a great distance. Yet you dallied for a whole month before you advanced, resulting in the bandits being able to make plans as they wished. They were able to spy on your strengths and weaknesses and this resulted in the defeat of our army, and brought shame to the country and harm to our authority. Not only have you failed in the task the Court has given you, but you have disgraced your father and elder brother. Now the Court ministers have submitted a memorial of impeachment against you. Wu Liang and so on have already been sent to the judicial offices for investigation. Considering the achievements of your father and your brother, I am especially pardoning you and am simply demoting you. You will remain regional commander. The Court ministers' memorial is enclosed for you. Study it carefully and strive hard to atone. Do not be remiss in this!"
Zhong-yang Yan-jiu yuan Ming Shi-lu, volume 25, page 1291/92