veggiedog:Knowledgeable people tend to be more knowledgeable than they think they are compared to people that lack knowledge (i.e. people that lack knowledge tend to be less knowledgeable than they think they are).
If you know you don't know anything, that's something you *do* know. Someone newly certified as, for example, a rescue diver, with only 25 dives logged over the last six years since they first got their OW, is probably more likely to think "I've been diving for years!" and overestimate their skills relative to someone who's only been diving for six months before taking the rescue course, who also has 25 logged dives and is collecting c-cards like McDonalds Monopoly pieces, but realizes "I've only been diving a few months, even if I am certified, I'm sure I really don't know squat!"...