New Understanding of the Basic Theory of Traditional Chinese Medicine
ZHOU Jun
ABSTRACT traditional Chinese medicine (TCM) plays an important role in the medical system used in health care and treatment of diseases. This article reviews the basic theory of TCM based on its formation and contributions. Two new personal points are proposed as follows: Six Zang theory and deemphasization of the five-element theory. The basic theory of Chinese herbs is also discussed.

KEY WORDS  new understanding, yin-yang theory, five-element theory, six Zang and six Fu, traditional Chinese medicine Traditional Chinese medicine (TCM) is an important medical system used in health care and  treatment of diseases and it is regarded as a treasure for well being by the Chinese nation. This article reviews the basic theory of TCM to promote its use throughout the world. I have been dedicated to the study of Chinese herbs, focusing especially on their chemical composition. In the last 20 years, I have also studied the material basis and mechanisms of action of compound formulas of Chinese herbs. From this study, I began to understand the essential theory of Chinese herbs and basis for TCM. Actually, the herbs and TCM were not separated until the end of the Qing dynasty. This study only considers the knowledge found in the classic texts on TCM and does not include treatment practices.

Since it was not possible for me to read through all the TCM classics, I have focused here on the textbook TCM Basic Theory used in TCM colleges or universities. I also referred to classic texts for reference. In terms of Chinese herbs, I looked at the theories of Medica in books from different generations. I do not consider Chinese medical theory in the context of Western medicine here.

THE GREAT CONTRIBUTIONS OF TCM
In addition to food, clothing, shelter and transportation, human beings depend on health care and on prevention and treatment of diseases, or in other words, medicine, for survival. Medicine is essential to human survival. TCM theory originated from the practice of the prevention and treatment of diseases over time and then further developed through practice. Like the continuing advance of theories in social science and natural science, TCM theory has to keep pace with the times. The theory of the West is updated constantly, as should the basic theory of TCM be updated.

One of the great contributions of TCM was the population growth. Despite factors that could not be controlled, such as wars, famines and natural disasters that kept the population growth in check, TCM played a role in promoting the population growth through the prevention of diseases. The population of China increased to approximately 60 million from the end of the western Han dynasty to the end of the Ming dynasty, to 402 million at the end of the Qing dynasty, and to 450 million during the early Republic of China.

Another contribution that TCM has made to health care in China is the prevention of contagious diseases. The devastating pandemic diseases that occurred in European history claimed the lives of tens of millions of people. Similar diseases in China have as severe consequences as they did in Europe. The "Shang Han Lun", Treatise on Febrile Diseases) by ZHANG Zhong-jing was written for the prevention and treatment of epidemic diseases. Since the febrile diseases recorded in the Shang Han Lun were not necessarily all contagious conditions, the Wen Yi Lun, Treatise on Pestilence) by WU State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming (650204), China
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DOl 10.1007/s 11655-009-0007-y You-ke during the Qing dynasty complemented the Shang Han Lun in this regard.

There is a plethora of historical treatises on TCM that provide the foundation for TCM theory. They include the Huang Di Nei Jing, Yellow Emperor's Internal Classic), which was completed at the end of the western Han dynasty, and Shen Nong Ben Cao Jing, Shennong's Herbal Classic) at the end of the eastern Han dynasty. Other examples include Nan Jing, Classic on Medical Problems), Shang Han Lun, Qian Jin Fang, Essential Prescriptions Worth a Thousand Gold Pieces), Mai Jing, The Pulse), Ben Cao Jing Ji Zhu, Collective Notes on Herbals), Zhu Bing Yuan Hou Lun, General Treatise on Causes and Symptoms of Diseases), Tang-Xin Xiu Ben Cao, The Newly-revised Materia Medica in the Tang dynasty), Song-Zheng Lei Ben Cao, Classified Materia Medica in the Song dynasty) and Ming-Ben Cao Gang Mu, Compendium of Materia Medica in the Ming dynasty). Thanks to a great effort in sorting out and organizing classical works during the Qing dynasty, many TCM classics have been well preserved.

When discussing the great contribution of TCM, we must admit that China missed the historical opportunity of European Renaissance. The Renaissance started in Italy and then rapidly spread across the Europe, contributing to the prosperous development of natural science in the fifteenth century and the years that followed. The invention of the telescope and the microscope enabled the introduction of medicine-related fields of study, including anatomy, physiology and pathology. At the same time, the Ming dynasty was in decline in China. Kangxi (a Qing emperor) accepted quinine from a missionary for his malaria, but he neglected a treatise on human anatomy after having it translated into Manchu. The government during the Qing dynasty pursued a policy of isolation and rejected the achievements of the European Renaissance. In addition, the study of Confucianism played a part. Starting with DONG Zhong-shu's idea of "Rejecting all the other academic groups except Confucianism" during the western Han dynasty, the governments of the Sui, Tang, and Qing dynasties depended on the Imperial Examination System. Talented people sought good results in their examinations for fame or high social status. During this long period, those who practiced medicine shared inferior positions with witches and artisans. Some masters collected medical formulas, for instance, Su Shen Liang Fang, Effective Formulas Collected by SU Dong-po and SHEN Kuo). Those with advanced medical skills might be named as imperial doctors or distinguished doctors.

THE FORMATION OF THE BASIC THEORY OF TCM
Even before the western Han dynasty, records of the basic theory of TCM had been kept during the Zhou and Qin dynasties, for example, the Shi Ji, Historical Records) on BIAN Que-Cang Gong Lie Zhuan. However, the records included only specific case reports. The Huang Di Nei Jing is the earliest existing book on medical theory. Although some chapters have been lost, the general theoretical system of the book had been well preserved. The first sentence of the Nei Jing was "Huangdi was born magic and able to speak a little older. He was quick when young, sincere and diligent when grown and thus, became emperor in his adulthood", was undoubtedly copied from the Shi ji-Wu Di Ben Ji, Historical Records on Wu Di Ben Ji). Consequently, it is now commonly believed that individual chapters of the Nei Jing were completed during the late western Han dynasty. It is unlikely that the complete book of Shi Ji was copied from the Nei Jing (Referred to History of Ancient Chinese Medicine by ZHAO Pu-shan, 1997, Zhonghua Publishing House). The theoretical framework in the Nei Jing was based on a summarization of treatment practices before the western Han dynasty. Then, physicians in later generations wrote numerous works to interpret and develop the framework. The challenge we face today is to overcome the limitations and promote the strong points of TCM.

As far as the author of the Nei Jing is concerned, the Huai Nan Zi-Xiu Wu Xun states that, "Since the social conventions value ancient people but disvalue people today, the books have to be written in the name of Shennong or Huangdi to be passed down". The Nei Jing was written as a dialogue between Huangdi and Qibo. Who was Qibo I believe that Qibo was not a single person but a group of master physicians living in the Qishan (mountain) region near Chang'an city during the western Han dynasty. Some of them were acting as Huangdi raise questions, and some of them were acting as Qibo to answer these questions. The word Bo has many meanings and, here it means people with special skills. For example, Wenbo is a wise man and Shibo is a poet. Qibo means people with medical skills.

BASIC THEORY OF TCM
It is not practical to discuss all basic theories of TCM. I studied several versions of a textbook used today on the basic theory of TCM. The following ideas are based on the English-Chinese version of TCM Basic Theory edited by WU Chang-guo and translated by ZHU Zhong-bao (Shanghai TCM University Press, printed in 2002 and re-printed in 2005). Keep Yin-yang Theory and Deemphasize the Five-element Theory The yin-yang theory originated from the Guo Yu-Zhou Yu, Discourses of States on Discourses of Zhou) during the western Zhou dynasty, and the five-element theory originated from the Shang Shu-Hong Fan, the book of history on Hong Fan). They were philosophical theories used to interpret natural phenomena. The yin-yang theory was not introduced into TCM basic theory until the Nei Jing-Si Qi Tiao Shen Lun , Internal Classic on Four Types of Qi and Mind Regulation). The five-element theory was not discussed in detail in the Nei Jing, but it appeared earlier than the four-element theory in the Western world.

The reason for keeping yin-yang theory is that yin and yang signify essential signs and natures of human health conditions, including both external conditions such as cold, heat, warmth, seasons and ecosystems as well as internal conditions such as yin deficiency, yang deficiency, preponderance of yin or yang and deficiency of yin or yang. Although Western medicine also includes concepts like hyperfunction or hypofunction and augmentation or inhibition, the yin-yang idea occurred much earlier. The yin-yang theory embodies the holistic view of TCM and has more advantages in the treatment of diseases than Western medicine has. Although the yin-yang theory on treatment is holistic, disease-oriented treatment should be combined with compound formulas based on syndrome differentiation for acute attacks of emergent conditions. For example, the major herbs for contagious diseases such as malaria and bacterial or viral infections include Changshan (Radix Dichroae) and Qinghao (Artemisia annua L.) for malaria and Huanglian (Rhizoma Coptidis) for dysentery. Some TCM workers found that certain herbs have anti-viral actions. As a result, the holistic view of yin-yang theory is considered to be dialectical materialism.

The reason to deemphasize the five-element theory is that, except their applications to TCM theory, metal, wood, water, fire and earth are not used any longer to explain complicated natural phenomena. Actually, the five elements were not much discussed in the Nei Jing, except for one sentence in the Su Wen-Yin Yang Yin Xiang Da Lun, Chapter 5 of the Plain Questions), which states, "the alterations of four seasons and five elements contribute to cold, summer-heat, dryness, dampness, and wind, resulting in the regular laws of growth, change, transformation and storage". However, this sentence is more concerned with seasonal climates than with the diagnosis or treatment of disorders. The Su Wen-Zang Qi Fa Shi Lun, Chapter 22 of the Plain Questions) also states that "Five elements specifically refer to metal, wood, water, fire and earth. They can tell life or death and decide the qi of five-Zang organs". The basic theory of TCM described the corresponding relationships between the five elements and five Zang organs: metal-lung, wood-liver, water-kidney, fire-heart and earth-spleen. In addition, there are also corresponding relationships between the five elements and the Fu organs. Since the Zang-fu organs allow the diagnosis and treatment of diseases, why is five-element theory still necessary? As a matter of fact, from the Three Kingdoms (220-280), the Jin dynasty (265-316) to the Sui and Tang dynasties (581-907), important medical books such as the Shang Han Lun and Qian Jin Fang only mentioned yin, yang and the Zang-fu organs and never connected the five elements to the diagnosis or treatment of diseases. The physicians in later generations exaggerated the application of the five elements, for example, relating the five elements to the five liquids (snivel, tears, saliva, sweat and spittle).