Some call it energy, other akasha, some aura and some even call it soul. In the middle ages, many believed that everything was connected with substance called ether. As modern ages, we know about electrons, energy fields and atoms. Nothing still explains powers what spirits posses and what connects between us.
As many know, and even more believe to exists, everyone of us possess some amount of enegy. This energy used in our daily basis: Performing tasks, walking or even thinking. We devour our energy back by eating and relaxing and then again use it forward.
Witches and other of kind use this same energy in the magic to perform spells and rituals. Same energy used for daily tasks, can be constructed, drawn to and targeted to different kind of tasks. Although most of the time energy is invisible, some believe that the visions of ghosts and other spirits is consists of this same matter, and it is somehow a same thing that soul is made of.