During the mid-Tang Dynasty, the Huaining military governor Li Xilie rebelled, declaring himself Grand Marshal and King of Jianxing, and laid siege to Xiangyang. Emperor Dezong ordered the Jingyuan military governor Zhu Ci to relieve Xiangyang. As the Jingyuan troops passed through the capital Chang'an, the court refused them rewards, sparking a mutiny. The soldiers seized Chang'an and proclaimed Zhu Ci emperor of a new state called Qin. At that time, Zhu Ci's brother, the Lulong military governor Zhu Tao, had also rebelled and declared himself King of Ji.
Emperor Dezong of Tang fled from Chang'an to Fengtian, finding himself unable to eat or sleep well in his dire situation. Chancellor Lu Qi comforted him, "If we send a high minister to grant Zhu Ci higher titles and appease the Jingyuan troops, I believe Zhu Ci can still be brought back to the imperial court."
Emperor Dezong looked at the ministers who had fled with him and asked, "Who is willing to go?" The ministers, fearing they would be killed by Zhu Ci, all remained silent. Grand General Wu Xu said, "I will go!" After the court session, someone asked him, "Zhu Ci harbors treacherous intentions; this mission will surely end in disaster. Why don't you consider yourself and your family?"
Wu Xu said calmly, "I receive the court's salary, so I should die for the court. Now that the emperor is in danger, if I think only of myself in the face of crisis, I am no loyal minister. I know I will surely die on this mission, but for the emperor's sake, I must still take this risk."
Wu Xi set out that very day with the imperial decree, arriving at Zhu Ci's camp to explain the principles of righteousness and urge him to submit to the court. Zhu Ci refused to listen and had him killed.
Later, the idiom "Thinking Only of Oneself in Times of Danger" came to describe someone who, when facing a crisis or critical moment, considers only their own interests.
Source: *Old Book of Tang*, "Biography of Wu Xu"
Meaning of the Idiom: Later, the Chinese idiom "临危自计" came to describe how someone who when facing a crisis or critical moment considers only their own interests.