Sun Simiao (581-682) was a Taoist priest and a medical scientist in the Tang Dynasty. From Huayuan, Jingzhao (now Yaoxian County, Shaanxi Province). He was well-versed in the studies of various schools of thought, especially Laozi and Zhuangzi, and also had a good understanding of Buddhist scriptures. For a long time, he secluded himself in the Zhongnan Mountains, practicing medicine and being friendly with the famous monk Daoxuan. He once went to Mount Emei to refine the "Taiyi Divine Essence Pill". Emperor Taizong and Emperor Gaozong of Tang repeatedly summoned him to serve as an official in the capital, but each time he declined. He was determined to devote his entire life to the mountains and forests. In the second year of Chongning of the Northern Song Dynasty (1103), he was posthumously honored as "Miaoying Zhenren". It is said that he was skilled in yin-Yang divination and had no divine response. He combined the Taoist theory of health preservation with medicine, believing that if people want to live a long life, they must pay attention to their diet and daily routine, restrain their emotions and cultivate their nature, guide and promote the circulation of qi, and supplement with food and medicine in order to live out their natural years. He extensively collected folk remedies and secret prescriptions, summarized medical theories and medical practices before the Tang Dynasty, classified and recorded them, and made significant contributions in the fields of medicine and pharmacology. He was later honored as the "Medicine King". He believed that taking the golden elixir was a matter of "the divine path is distant and the traces are sparse", and thus regarded alchemy as a means of making medicine and treating diseases. It is believed that as long as "a good doctor guides them with medicine and cures them with injections", there is no incurable disease in the world. He has authored numerous works, mainly including "Thousand Gold Prescriptions", "Thousand Gold Wing Prescriptions", "Ming for Preserving Life", "Ming for Preserving the Spirit and Refining Qi", "Fang for Nourishing the Pillow", etc.