Working on my Druid grade I had this reflection about nwfre, the druidic concept for life force (similar to chi, ki or prana in other traditions):
Nwfre is the relationship between mind and body, and how attitude, mood, intention, motivation and other psychological factors (conscious and unconscious) affect our behaviour, perception and relationship with the environment.
If we have harmony between body and mind (i.e. nwfre is balanced and flowing) then harmony can also spread to our behaviour in the environment, and from there, manifest itself in our relationships. Perpection, key to understanding ki (pun intended), becomes refined and less distorted, and our reactions become more aligned to the nwfre that flows within our bodies and through our environment.
This is something I learning through the marshal art of aikido, which is a Discpline of Coordination as one writer puts it. Not just a coordination of left and right, arms and legs, but also between what I am thinking and what my body is doing. And between my body and the bodies that surround me. In the end it works for harmony between left and right, arms and legs, mind and body, and individual and environment; much of which works with the perception of ki.