Bing Shan Nan Kao

In the Tang Dynasy （618-907）， Emperor Xuanzong， whose name was Li Longji， extremely favored his consort Yang Yuhuan. After being titled the highest-ranking imperial concubine， Yang Yuhuan persuaded the emperor to appoint important positions to her family. Her cousin Yang Guozhong was appointed Prime Minister while he was also concurrently given forty official positions.

At that time， Emperor Xuanzong indulged himself in the comfort of Yang Yuhuan and ignored the governmental affairs. The court was completely controlled by Yang Guozhong， who had the right to appoint or remove governmental officials at his own will.

Then， there was an imperial candidate for official named Zhang Tuan. Without a connection to the nobility at the court， he was given little chance to work for the government. His friends asked him to visit and befriend Yang Guozhong， who was believed to be able to give Zhang Tuan an important position， so that he could become a rich noble.

But Zhang Tuan rejected this suggestion and never went to Yang Guozhong for help. Instead， he warned his friends who wanted to throw themselves into Yang Guozhong that the man was not as reliable as he seemed to be.

“You think Yang Guozhongs position is as stable as Mount Tai， but I just consider him as an iceberg. Without any real talents， he is not suited to govern a country. And look at the chaos he caused. I am sure that there will be an unrest in the future， which will rupture his position as the sun melts down the iceberg. By then you will see that you lose your backing.”

Zhang Tuans prophecy eventually proved true as An Lushan staged a revolt years later. The rebel army overtook the capital， forcing Emperor Xuanzong to run from the city to Sichuan along with Yang Guozhong and Yang Yuhuan. During their fugitive march， the soldiers coming with the trio were greatly angered by Yang Guozhong， blaming him for the harsh situation. They turned their swords to Yang Guozhong and killed him. They also confronted Emperor Xuanzong， forcing the emperor to kill his consort.

After that， the backing provided by Yang Guozhong indeed collapsed.