My own understanding of 'ki' is just 'energy'. Energy of mind, energy of body, or the energy of spirit - not in a mystical sense, but in the sense of.. someone being spirited ;p. If that's unified into good intention - whether it be delivering an attack with strong intent, or executing a technique in a flowing, strong and intentional manner - then I'd call it ki. That's just my view of it. Everyone perceives things differently
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