Shen Nong Ben Cao Jing

Legendary story says that Shen Nong (God of Agriculture) tasted hundreds of herbs and was poisoned seventy times a day. This story actually talks about differentiation of edible plants. However in the book entitled Huai Nan Zi (Book of the Master of Huainan) compiled in the Han Dynasty, it was taken as the first trial of studying materia medica. That is why the God of Agriculture was also worshiped as the father of medicine. Shen Nong Ben Cao Jing (Agriculture God's Canon of Materia Medica) is the earliest extant classics about material medica compiled in the Eastern Han Dynasty.

Shen Nong Ben Cao Jing was lost in history. It was recompiled by scholars in modern times by collecting the original materials of it from many other books. Shen Nong Ben Cao Jing was regarded as the authentic canon of materia medica in all dynasties. So the quotations from it can be found in many books written after it. According to these quotations, we can know that about 365 kinds of herbs were studied in Shen Nong Ben Cao Jing.

These herbs were classified into three grades, first grade, second grade and third grade. The first grade of herbs can be used to invigorate the body and prolong life; the second and the third grades of herbs are toxic and thus can be used to treat diseases. But they cannot be taken more and for a long time. The discussion of each herb covers the aspects of name, taste, property, indication, place of production and alternate names.