Ki (“spirit / feeling / psyche / energy”) is a primal feeling of aliveness; the sensation of synergy; the [Friedrich_Nietzsche Nietzschean] Will to Power -- the aetherial, vital essence of life itself. Ki is also commonly referred to as c’hi, qi, or prana -- though mostly by energy healers, Traditional Chinese Physicians, and other charlatans.
While this sounds like the Force from Star Wars, there is nothing mystic nor magical about the martial arts. There is no one who can shoot fireballs, cure diseases, deal no-touch knockouts, or do anything remotely supernatural or superhuman with their ki -- such claims are confidence tricks designed to exploit the naïve -- and we dare you to prove us wrong. Historically, “ki” was cited whenever teachers did not know or could not explain the real answer, because of an Asian cultural nuance where it is considered unspeakably rude not to answer a question -- even if it meant providing wild speculations. This was especially true in marital arts circles because of:
- A lack of scientific methodology.
- Unquestioning conformity. Teachers taught, and students listened, with no questioning, which allowed for uncertainty to propagates onto future generations.
- Flowery, poetic languages. Since nothing could be specifically addressed, concrete discussion was impeded.
Ki, though wonderful, is a fairly mundane thing -- a coordination one’s mental focus and bio-mechanical efficiency, resulting in effortless, optimized fluid motion. This is achieved through kokyū, the coordination of breathing and body movement. In general, any time a technique directs your power (or your limbs) out away from you, you need to slowly exhale, like in weightlifting. Likewise, you must quickly inhale while rechambering after a series of techniques.