Apparently, Ghi energy is the very essence of life force. The theory is that the Animated exist because there has been an excess amount of this life force introduced to our world, by some unknown means. But it's become apparent that every living being on Gaia has some reserve of this Ghi energy within them and that all living things are connected in our world. The rings we use in battle are powered by this force, and it seems to be the long-elusive component that defines the difference between 'living' and 'non-living' matter.