There are books as evidence:
There are some records in ancient books about Shennong's taste of herbs and the identification of medicinal properties:
According to the "Historical Records" of the Western Han Dynasty: "Shennong He whipped grass and trees with ocher and began to taste hundreds of herbs. "Huainanzi" records: "Shennong tasted the taste of hundreds of herbs and the sweetness and bitterness of water springs." "Sou Shen Ji" says: "Shennong whipped hundreds of herbs with ocher whips, fully knowing their flat, poisonous, cold and warm properties, and the odor..."
"Tongzhi" written by Zheng Qiao in the Song Dynasty said : When Shen Nong tasted hundreds of medicines, "...all tasted them orally and tried them personally, and encountered seventy poisons in one day... and obtained three hundred and sixty medicines... Later generations passed it down as a book, called "Shen Nong's Materia Medica" "
Luo Mi's "Lu Shi" of the Song Dynasty said: Emperor Yan Shennong "rubbed the lips, checked the color and smell, and tasted the vegetation to correct the name. Evil, discern its ministers... seventy poisons can occur in one day, and it is extremely qi-containing... The medicine is positive for three hundred and sixty-five times.
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