Pinyin is y and b and shzh and u s and,

It means to describe noble integrity and swear to death without having anything to do with unjust or immoral people.

From Historical Records Biography of Boyi.

It's about Boyi and Shu Qi.

At the end of Shang Dynasty, the monarch of the isolated bamboo country in eastern Hebei had two sons, the older one was Boyi, and the younger one was Shu Qi. Zhu Guo liked his youngest son, Shu Qi, and made a will to let Shu Qi succeed him. After his father died, Shu Qi didn't want to violate the rule of making the eldest son king, and insisted on giving way to his younger brother. Boyi secretly ran away from home in order to let his younger brother settle down to be a monarch. After his brother left, Shu Qi also left the palace, looking for his brother everywhere. After the reunion, they decided not to return to that lonely bamboo village.

I heard that Xibochang (that is, Zhou Wenwang) respected the elderly, so the two brothers defected together and settled there. After King Wen died, King Wu succeeded to the throne. After King Wu succeeded to the throne, he expanded his power and prepared to crusade against Shang and Zhou Dynasties. When the troops of the Zhou Dynasty entered today's Jin Meng area, Boyi Shu Qi seized the opportunity to run over, detained the horses and protested that Zhou Wuwang's actions were unfilial and unfriendly. Hearing this, King Wu's soldiers were very angry and pulled out their knives to kill them. Fortunately, Jiang Taigong stopped them. Jiang Taigong said, "These are two moral people." And asked the soldiers not to embarrass them.

Successfully cutting Zhou, the world is unified as Zhou. Boyi and Shu Qi think this is a shameful thing. They are determined not to be Zhou Chen or eat Zhou Su. The two brothers left the ruling area of the Zhou Dynasty and lived in seclusion in a place called shouyangshan, where they collected Osmunda japonica from the mountains to satisfy their hunger. A woman saw them and said, "You don't eat the grain of the Zhou Dynasty. The wild vegetables you are picking now are also planted on the land of the Zhou Dynasty!" " Hearing this, they thought that everything in the world belonged to the Zhou Dynasty and decided to starve to death. On his deathbed, he sang a song saying, "You don't know it's your fault to replace tyranny with tyranny." The heyday of Shennong, Yu Shun and Yu Xia suddenly disappeared without a trace. Where do we end up? "