I've actually thought about the point you make quite a bit. I agree with you in many ways, but I'm not sure everything can be explained that way. One thing I have noticed throughout my life is that almost all the nightmares I have had while sleeping, occurred when I was physically sick with a virus, occurred after eating a meal that caused mild food poisoning, or when I was on some sort of man-made medication. There is definitely more going on than just the spiritual, and there is definitely more going on than just the physical. Everything seems to be tied together but there's also a balancing act going on between spiritual, physical, and each person's own sense of self. Problems with one can affect the others in pretty big ways.

There is free-will to a point, there is self-determination to a point, there is external influence acting upon you to a point, and there is spiritual influence acting over you to a point. I think that's part of what makes life so challenging but interesting at the same time. There is no end point of understanding that can be reached in this life, only deeper and deeper levels of complexity that can be better understood.