In traditional Chinese culture, qi (simplified character: 气; traditional: 氣), ki in Japanese, is a dynamic and transformative principle that operates inside all living beings as well as in the universe at large.
It is often appealed to as an explanation for a variety of effects in alternative medicine including acupuncture, martial arts, feng shui, and is a part of the religious and philosophical ideas of Daoism.
Classical Chinese medicine
In classical Chinese medicine, qi-based explanations of wellness and disease were proposed, perhaps as early as 400 BC, as an alternative to older concepts involving possession or revenge by spirits and ghosts. The human body's innate qi, supplemented by qi that the body derived from food and air, was thought to be stored and circulated in different ways by various internal organs. The body and its organs and circulatory channels contained different types of qi at any given time. Some were associated with the female/dark/moist yin principle and others with the male/bright/dry yang principle (see yin and yang and traditional Chinese medicine); moreover, they were also associated with the five Chinese "elements" or "phases": wood, water, fire, metal, and earth. Imbalances in these associations and correspondences were thought to cause diseases, and drugs and other treatments associated with yin or yang and specific "elements" could correct imbalances and restore health. A patient's individual circumstances, as well as the season of the year and other environmental factors, also needed to be taken into account in a doctor's consideration of the state of a patient's qi.
Diagnosis of qi imbalances, blockages, deficiencies, excesses, and so forth, and thus diagnosis of diseases and determination of appropriate treatments, was thought to require several techniques. These included taking a patient's medical history; observing the patient's appearance, especially that of the tongue; observing breath and bodily odors; and taking pulses at the wrists.
Scientific views of qi
Many people deny qi on scientific grounds (or see it as a metaphor rather than a real force), pointing to the better explanations given by science for the effects that qi is supposed to bring about. In martial arts, those who have Westernized and secularised the martial arts point to the physical laws of motion and the scientific understanding of physiology and psychology as a better explanation of the techniques taught by martial artists. Scientific studies of acupuncture shows that the claimed effects of acupuncture can be achieved by insertion of acupuncture needles along qi-based meridian lines by random insertion of needles (as well as use of retracting "fake needles"). With feng shui, different feng shui consultants who claim to be able to tap into the power of qi, examining the same physical location, may produce different recommendations.
There are a variety of ways to Romanize Chinese words and characters: qi is the correct spelling in pinyin, which is the Romanization scheme approved by the Chinese government and used by most western scholars today. "Ch'i" (note apostrophe) is the correct spelling in the Wade-Giles system, which was widely used before pinyin, survives in many older texts, and is still used by some western scholars today.
The Japanese name for the same concept is ki, and the Korean name is gi.
"Qi", or a related word from another East Asian language, occurs in a number of expressions:
- Qigong, a Chinese system of energy exercises
- Reiki, a Japanese system of healing
- Aikido, a Japanese martial art
- Yi-Li Wu, Reproducing Women: Medicine, Metaphor, and Childbirth in Late Imperial China (Berkeley: Univ. of California Press, 2010), 23-25.
- Stephen Barrett, Be Wary of Acupuncture, Qigong, and "Chinese Medicine", Quackwatch.