Which it is but it is also correspondence between the spirit dimensions and our physical world, and sometimes, all three.

Regarding the correspondence between the inner and outer worlds, are you familiar with the concept of a mirror coincidence (you probably are). A mirror coincidence can have no signaling value, i.e., not answer any questions but merely reflect one's present state, or it could be that and also have signaling value. Anyone interested can read my https://medium.com/channspirations/mirror-coincidences-41893e2e55ed

Anyway, this essay of yours Graham is one of my favorite's so far, not that the others lack for anything, but because the topics presented are the most connected to my own Journey to the East (title of a Hesse book). I have the Wilhelm I Ching with Jung's forward in my partially read pile. Maybe one day it will emerge for further use.