Feng shui (风水, 風水) adalah ilmu topografi kuno Tiongkok yang mempercayai bagaimana manusia dan Surga (astronomi), dan Bumi (geografi), hidup dalam harmoni, untuk membantu memperbaiki hidup dengan menerima Qi positif. Qi terdapat di alam sebagai energi yang tidak terlihat. Qi baik disebut juga napas kosmik naga, jenis Qi ini dipercaya sebagai pembawa rejeki dan nasib baik.
Karakter qi dalam kaligrafi penulisan bahasa Korea
Qi (Hanzi: 氣, Kanji: 気) atau lebih sering dieja sebagai chi atau ch'i (dalam Romanisasi gaya Wade-Giles) atau ki (dalam ejaan Romaji bahasa Jepang) adalah sebuah konsep dasar budaya Tionghoa. Qi dipercayai adalah bagian dari semua makhluk hidup sebagai semacam "kekuatan hidup" atau "kekuatan spiritual". Kata ini seringkali diterjemahkan sebagai "aliran energi" atau secara harafiah sebagai "udara" atau "napas".
Dalam aksara Hanzi atau Kanji, qi ditulis sebagai 氣 atau 気. Menurut tradisi, karakter ini ditafsirkan sebagai "asap kukus (气) yang naik dari nasi (米) yang masak."
The etymological explanation for the form of the qi logogram in the traditional form 氣 is “steam (气) rising from rice (米) as it cooks”. The earliest way of writing qi consisted of three wavy lines, used to represent one's breath seen on a cold day. A later version, 气, identical to the present-day simplified character, is a stylized version of those same three lines. For some reason, early writers of Chinese found it desirable to substitute for 气 a cognate character that originally meant to feed other people in a social context such as providing food for guests. Appropriately, that character combined the three-line qi character with the character for rice. So 气 plus 米 formed 氣, and that is the traditional character still used today (the oracle bone character, the seal script character and the modern "school standard" or Kǎi shū characters in the box at the right show three stages of the evolution of this character).
In the Japanese language, the Chinese character corresponding to "qi" (氣) is pronounced 'ki'. The Japanese language contains over 11,442 known usages of "ki" as a compound. As a compound, it tends to represent syllables associated with the mind, the heart, feeling, the atmosphere, and flavor.
References to things analogous to the qi taken to be the life-process or flow of energy that sustains living beings are found in many belief systems, especially in Asia. In Chinese legend, it is Huang Di (the Yellow Emperor) who is identified as the one who first collected and formalized much of what subsequently became known as traditional Chinese medicine.
Philosophical conceptions of qi from the earliest records of Chinese philosophy (5th century BC) correspond to Western notions of humours. The earliest description of qi in the current sense of vital energy is due to Mencius (4th century BC).
Within the framework of Chinese thought, no notion may attain such a degree of abstraction from empirical data as to correspond perfectly to one of our modern universal concepts. Nevertheless, the term qi comes as close as possible to constituting a generic designation equivalent to our word "energy". When Chinese thinkers are unwilling or unable to fix the quality of an energetic phenomenon, the character qi (氣) inevitably flows from their brushes.
The ancient Chinese described it as "life-force". They believed qi permeated everything and linked their surroundings together. They likened it to the flow of energy around and through the body, forming a cohesive and functioning unit. By understanding its rhythm and flow they believed they could guide exercises and treatments to provide stability and longevity.
Although the concept of qi has been important within many Chinese philosophies, over the centuries the descriptions of qi have varied and have sometimes been in conflict. Until China came into contact with Western scientific and philosophical ideas, they would not have categorized all things in terms of matter and energy. Qi and li (理, li, pattern) were 'fundamental' categories similar to matter and energy.
Fairly early on, some Chinese thinkers began to believe that there were different fractions of qi and that the coarsest and heaviest fractions of qi formed solids, lighter fractions formed liquids, and the most ethereal fractions were the "lifebreath" that animates living beings.
Yuán qì is a notion of innate or pre-natal qi to distinguish it from acquired qi that a person may develop over the course of their lifetime.
The earliest texts that speak of qi give some indications of how the concept developed. The philosopher Mo Di used the word qi to refer to noxious vapors that would in due time arise from a corpse were it not buried at a sufficient depth. He reported that early civilized humans learned how to live in houses to protect their qi from the moisture that had troubled them when they lived in caves. He also associated maintaining one's qi with providing oneself adequate nutrition. In regard to another kind of qi, he recorded how some people performed a kind of prognostication by observing the qi (clouds) in the sky.
In the Analects of Confucius, compiled from the notes of his students sometime after his death in 479 B.C., qi could mean breath, and combining it with the Chinese word for blood (making 血氣, xue-qi, blood and breath), the concept could be used to account for motivational characteristics.
The [morally] noble man guards himself against three things. When he is young, his xue-qi has not yet stabilized, so he guards himself against sexual passion. When he reaches his prime, his xue-qi is not easily subdued, so he guards himself against combativeness. When he reaches old age, his xue-qi is already depleted, so he guards himself against acquisitiveness.
—Confucius, Analects, 16:7
Mencius described a kind of qi that might be characterized as an individual's vital energies. This qi was necessary to activity, and it could be controlled by a well-integrated willpower. When properly nurtured, this qi was said to be capable of extending beyond the human body to reach throughout the universe. It could also be augmented by means of careful exercise of one's moral capacities. On the other hand, the qi of an individual could be degraded by averse external forces that succeed in operating on that individual.
Not only human beings and animals were believed to have qi. Zhuangzi indicated that wind is the qi of the Earth. Moreover, cosmic yin and yang "are the greatest of qi." He described qi as "issuing forth" and creating profound effects. He said "Human beings are born [because of] the accumulation of qi. When it accumulates there is life. When it dissipates there is death... There is one qi that connects and pervades everything in the world."
Another passage traces life to intercourse between Heaven and Earth: "The highest Yin is the most restrained. The highest Yang is the most exuberant. The restrained comes forth from Heaven. The exuberant issues forth from Earth. The two intertwine and penetrate forming a harmony, and [as a result] things are born."
"The Guanzi essay 'Neiye' 內業 (Inward training) is the oldest received writing on the subject of the cultivation of vapor [qi] and meditation techniques. The essay was probably composed at the Jixia Academy in Qi in the late fourth century B.C."
Xun Zi, another Confucian scholar of the Jixia Academy, followed in later years. At 9:69/127, Xun Zi says, "Fire and water have qi but do not have life. Grasses and trees have life but do not have perceptivity. Fowl and beasts have perceptivity but do not have yi (sense of right and wrong, duty, justice). Men have qi, life, perceptivity, and yi." Chinese people at such an early time had no concept of radiant energy, but they were aware that one can be heated by a campfire from a distance away from the fire. They accounted for this phenomena by claiming "qi" radiated from fire. At 18:62/122, he too uses "qi" to refer to the vital forces of the body that decline with advanced age.
Among the animals, the gibbon and the crane were considered experts in inhaling the qi. The Confucian scholar Dong Zhongshu (ca. 150 BC) wrote in Luxuriant Dew of the Spring and Autumn Annals: "The gibbon resembles a macaque, but he is larger, and his color is black. His forearms being long, he lives eight hundred years, because he is expert in controlling his breathing." ("猿似猴。大而黑。长前臂。所以寿八百。好引气也。")
Heaven (seen here as the ultimate source of all being) falls (duo 墮, i.e., descends into proto-immanence) as the formless. Fleeting, fluttering, penetrating, amorphous it is, and so it is called the Supreme Luminary. The dao begins in the Void Brightening. The Void Brightening produces the universe (yu-zhou ). The universe produces qi. Qi has bounds. The clear, yang [qi] was ethereal and so formed heaven. The heavy, turbid [qi] was congealed and impeded and so formed earth. The conjunction of the clear, yang [qi] was fluid and easy. The conjunction of the heavy, turbid [qi] was strained and difficult. So heaven was formed first and earth was made fast later. The pervading essence (xi-jing) of heaven and earth becomes yin and yang. The concentrated (zhuan) essences of yin and yang become the four seasons. The dispersed (san) essences of the four seasons become the myriad creatures. The hot qi of yang in accumulating produces fire. The essence (jing) of the fire-qi becomes the sun. The cold qi of yin in accumulating produces water. The essence of the water-qi becomes the moon. The essences produced by coitus (yin) of the sun and moon become the stars and celestial markpoints (chen, planets).
There have been a number of studies of qi, especially in the sense used by traditional Chinese medicine and acupuncture. These studies have often been problematic, and are hard to compare to each other, as they lack a common nomenclature. Some studies claim to have been able to measure qi, or the effects of manipulating qi, such as through acupuncture, but the proposed existence of qi has been rejected by the scientific community.
A United States National Institutes of Health consensus statement on acupuncture in 1997 noted that concepts such as qi "are difficult to reconcile with contemporary biomedical information." In 2007 the MD Anderson Cancer Center at the University of Texas published an article  covering the concepts by which qi is believed to work and research into possible benefits for cancer patients. A review of clinical trials investigating the use of internal qigong for pain management found no convincing evidence that it was effective.
The traditional Chinese art of geomancy, the placement and arrangement of space called feng shui, is based on calculating the balance of qi, interactions between the five elements, yin and yang and other factors. The retention or dissipation of qi is believed to affect the health, wealth, energy level, luck and many other aspects of the occupants of the space. Attributes of each item in a space affect the flow of qi by slowing it down, redirecting it or accelerating it, which purportedly directly impacts the energy level of the occupants. Feng shui is said to be a form of qi divination.
Demonstrations of qi or ki power are popular in some martial arts and may include the immovable body, the unraisable body, the unbendable arm and other feats of power. All of these feats can alternatively be explained using biomechanics and physics.