The argument is that hallucinatory thinking may appear random but really has an underpinning logic. It's a non-binary logic about intermediary status between, or the union of, opposites. It's about threshold crossing and transformation. When ideas and feelings are too powerful to handle directly, they generate shadow forces. Reflections get projected. This is described with reference to myths of various cultures and occasionally to Shakespeare.
The style is either postmodern theory (with which I have little familiarity or skill) or poetry. If you try to read this purely analytically, it'll be slow going. You may need some kind of connection to the topic like some familiarity with a Frazer Golden Bough or Campbell Hero's Journey approach to myth or a relevant personal experience as well as a willingness to read this essay like a poem.