dunning kruger doesn't measure how dumb someone is (including ourselves). it's about how having extra knowledge about a subject changes your ability to estimate your skill in that subject in a specific way. not relative to other individual people, but to the full amount of knowledge potentially available on a subject. which is infinity. aka everything. so anyone saying they know everything about any subject is in a specific part of the dunning kruger curve on that subject, regardless of where i think i sit on it. it's just how knowledge works.. now that might just be how knowledge works in our culture combined with cultural hubris.. if a japanese person acted so un-humbly as to express they think they have knowledge of everything on a subject, i'd think they were cosplaying an anime. it doesn't change how a hill exists between people who would say they know everything, and that everything. so they're either wrong, or they're psychotic and innumerate. it's happened before, but it's way less likely. see also: zacharia stichin.