Description
According to traditional Chinese medical theory, ''jing'' or ''essence'' can be summarised in two parts: the yin, being congenital or prenatal, and the yang, being postnatal or acquired. Prenatal ''jing'' is acquired at birth from the parents: the father's sperm and the mother's ovum. Postnatal ''jing'' is acquired after birth through food, water, oxygen, as well as environmental and social conditions. The concept is expounded in the Bagua and within the '' I Ching''. The yin and yang ''jing'' transform to create and replenish each other. The yang ''jing'' circulates through the eight extraordinary vessels and transforms to become and replenish yin; in turn the marrow becomes blood, body fluid and semen. ''Jing'' should not be confused with the related concept of ''jin'' (; "strength" or "energy"), as in '' Neijin'' meaning "internal power", nor with ''jīng'' (; "classic"), which appears in many early Chinese book titles, such as the '' Huangdi Neijing'', '' Yijing'', and '' Chajing''.Allocation
One is said to be born with a fixed amount of ''jing'' (prenatal ''jing'' is sometimes called '' yuanqi'') and also can acquire ''jing'' from food and various forms of stimulation (exercise, study, meditation). Theoretically, ''jing'' is consumed continuously in life; by everyday stress, illness, substance abuse, sexual intemperance, etc. Prenatal ''jing'' is very difficult to be renewed, and it is said it is completely consumed upon dying.Restoration
''Jing'' is therefore considered quite important for longevity in traditional Chinese medicine; many disciplines related to qigong are devoted to the replenishment of "lost" ''jing'' by restoration of the post-natal ''jing'' and transformation of '' shen''. In particular, the internal martial arts tai chi, the Circle Walking of Baguazhang and the middle path of Wuxingheqidao may be used to preserve pre-natal ''jing'' and build post-natal ''jing'', if performed correctly. In traditional Chinese herbal medicine, ginseng is widely used to bolster and support the ''jing''. An early mention of the term in this sense is in a 4th-century BCE chapter called '' Neiye'' "Inner Training" of a larger text compiled during theSee also
*References
Further references
* Chang, Stephen T. The Great Tao; Tao Longevity; Stephen T. Chang * Kaptchuck, Ted J., The Web That Has No Weaver; Congdon & Weed; * Maciocia, Giovanni, The Foundations of Chinese Medicine: A Comprehensive Text for Acupuncturists and Herbalists; Churchill Livingstone; * Ni, Mao-Shing, The Yellow Emperor's Classic of Medicine : A New Translation of the Neijing Suwen with Commentary; Shambhala, 1995; * Holland, Alex Voices of Qi: An Introductory Guide to Traditional Chinese Medicine; North Atlantic Books, 2000; * Unschuld, Paul U., Medicine in China: A History of Ideas; University of California Press, 1985; * Graham, A.C. Disputers of the Tao: Philosophical Argument in Ancient China (Open Court, 1993). * Scheid, Volker, Chinese Medicine in Contemporary China: Plurality and Synthesis; Duke University Press, 2002; * Porkert, Manfred ''The Theoretical Foundations of Chinese Medicine'' MIT Press, 1974 * Hongyi, L., Hua, T., Jiming, H., Lianxin, C., Nai, L., Weiya, X., Wentao, M. (2003) Perivascular Space: Possible anatomical substrate for the meridian. Journal of Complementary and Alternative Medicine. 9:6 (2003) pp851–859 *Wang, Mu