The fourteenth year of Hongwu, on the eve of Zhu Su's appointment as a vassal prince.
Zhu Su woke up to find himself the fifth son of Zhu Yuanzhang.
In the Eastern Palace, seven-year-old Zhu Xiongying was vomiting and suffering from diarrhea. He couldn't keep down food or water and was already unconscious. The imperial physicians were helpless. The palace maids and eunuchs knelt across the floor, waiting for thunder from the heavens.
He rolled up his sleeves. "Bring me warm water, salt, and sugar."
When Zhu Yuanzhang arrived, he saw Zhu Su giving water to his eldest grandson.
"Fifth son, what are you giving my grandson?"
"Something that will save his life."
After that night, the crown prince's eldest son, who had been destined to die young, survived.
Later, Empress Ma did not die of illness, Zhu Biao did not die young, crops grew in Kaifeng's saline-alkali fields, and epidemics could no longer claim tens of thousands of lives.
Someone asked why he turned away from power and spent his days in the fields and beside medicine stoves.
Zhu Su simply said, "I can't stand to see people die, and I can't stand to see the common people go hungry."
Years later, the medical texts he compiled saved countless lives, and the crop varieties he cultivated spread across the land.
History would call him the Sage of Agriculture and the Sage of Medicine.
