In traditional Chinese culture, qì (also chi or ch’i)is an active principle forming part of any living thing.Qi is frequently translated as life energy, lifeforce, or energy flow.

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.

The earliest texts that speak of qi give some indications of how the concept developed.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.

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 adverse 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.

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 phenomenon by claiming “qi” radiated from fire. At 18:62/122, he also uses “qi” to refer to the vital forces of the body that decline with advanced age…