This attempt to see mind from a biological point of view is weak at best.
The topic is exorcism. I won’t be focusing on the practices of any particular faith, but rather the principles that run all throughout world cultures and lore regarding exorcism and the circumstances around it.
The practice of exorcism, in most cultures, assumes the native presence of spirits in the world itself. Whether these spirits are seen as evil or merely disruptive differs between one school of thought and another, but the power behind exorcism is always dependant on there being an overriding balance that can be maintained and restored.
Each aspect of the spirit world exists in relationship to all others. The heavens have a hell, the living world has a dead side, etc., and there is no solid barrier between these domains or planes of existence. Patterns of energy, or laws if you will, permit an exchange between one plane and the other, perhaps not unlike the laws of physics.
Overall, the structures we understand as normal space and time have no relevance on this level. Distance of any kind is not a factor. Things function more along a rule of resonance or sympathy. Like falls into the same space as like, birds of a feather flock together, as they say. So from time to time, you get a sort of immigration between planes, if you will. Something unusual happens, and it opens a door for a previously foreign presence to move into a space, or state of being, it normally cannot occupy. This is generally rather disturbing to the natives no matter what the intentions of the new comer might be, as it usually strains the web of spiritual energies in the environment.
In the oldest lore, the presence of a new spirit in a community wasn’t automatically seen as a bad thing. The new comer was sometimes seen as a herald of good fortune, positive change, but just as often the new spirit was found to be causing confusion and misfortune for the people residing there, and the spirit had to be dealt with. The view of spiritual horror and violence we typically imagine today is new. It was usually more of a case of communal disruption and disharmony, like having to tell children not to disturb the cattle or sheep.
I imagine it happens fairly often today, but we don’t see it for what it is and just shrug them off as disturbances? And tensions are greater as well.
Why did it all of a sudden become evil to be possessed? It was an easy way to get revenge on a girl back in those days when they had trials for witchcraft. They would accuse her of being a witch. With the rise of human leadership as the only source of guidance, most pronounced after what they call the age of reason, but existing even before then.
Your thoughts are welcome. Be well friends.