As one can see from its three disciplines, there is a focus in this class of unseen things that impact the current situation. Just as the classic magician "formula" of Hocus Pocus reveals something that was previously unseen, the discipline of Hocus Pocus makes qualities seen which are not a visible. Mathamancy is a manipulation of symbols that represent quantity or the count of occurrences of some group of objects, but is not seen. Findamancy involves the "location" of something, which only is visible through the invisible quantities of "longitude" and "latitude" or "GPS coordinates" which are not seen. Predictamancy involves the future of events and situations, which have not occurred, and thus are also not seen.
Parson calls them the Hokey Pokeys.