Traditional Chinese medicine and its herbal tradition developed alongside popular pharmacopoeia. It took off from the Huang Di Neijing, a text established between the 2nd century BC. B.C.And the 1st century AD, from precise observations of nature based on a thorough knowledge of the mechanisms which subject all life to natural laws. This text contains the two fundamental theories of Chinese medicine, namely the bipolarity of the cosmos (principles of ying and yang) and the five elements (wu xing).Living in harmony with these principles is the key to health and longevity. According to the Huang Di Neijing, certain men once lived to be a hundred years old, because they had such a robust constitution that incantations were enough to cure them. But recently, when potential energy, the basis of all life, or qi, declined, and men "overworked themselves...And distanced themselves from the joys of life", herbalism, acupuncture and others specialties of Chinese medicine appeared indispensable to men.