The universe and the interior of the human body are filled with the most fundamental life force, which they call "Qi". You can imagine it as an omnipresent "life energy", which is not as specific and measurable as an electric current, but it is the driving force behind all life activities. Breathing, heartbeat, thinking, growth - behind all these phenomena, it is believed that "Qi" is flowing and operating. It connects the body and the spirit, as well as the individual and the natural universe.
For the human body itself, this energy is specifically manifested in the three aspects of "jing, qi, and shen". "Jing" is the material basis of energy, similar to the gasoline in a car, being the most fundamental fuel reserve for the body, derived from our innate inheritance and subsequent diet. "Qi" is the very power that enables the car to start and move, being the driving force for the flow of blood and the cycle of breathing. "Shen" is the brilliance and mental state that this energy presents, like the headlights of the car and the smooth operation system, manifested as one's consciousness, thinking, and spirit. These three aspects form a whole: without fuel (jing), there would be no power (qi); without power, it is impossible to display brilliance (shen).
Therefore, the entire cultivation system of Taoism, including meditation, breathing exercises, and practicing Tai Chi, all aim at regulating and transforming these energies. Their goal is to conserve and replenish the innate fuel (preserving essence), by means of deep breathing and mental guidance to unblock and enhance the body's vitality (refining qi), and ultimately to make the mind clear, peaceful, and transcendent (nurturing the spirit). This process is essentially one of refining and elevating the raw energy, allowing life to return to its most harmonious and vigorous original state, thereby achieving the states of health preservation, longevity, and even unity with the cosmic law.
