Some heavy stuff, man.

"There is an intimate relationship between what is wise and what exists, although that relationship is subtle."

The narrator in VALIS gives us the delicious quote above. As so as a I read that line, I whipped out a pen and pad, scrawled it out, and furiously underlined it. So much of the novel is about what fundamentally exists.  Fat believes Zebra to be real, therefore to him, it is real; the narrator believes Fat to be real, so he is; the "commune" wishes for the daughter to be a Christ figure, so she dies. The very idea of VALIS, an AI in space creating reality around us is essentially concerned with the idea that the omnipotent being above us has omnipotence, or rather, is wise. That being need not be rational or irrational, a concept on which Fat and the narrator trip up so often upon.