“…named for the condition of a family friend who spoke in an oracular style on all subjects after becoming dominant in the shoe button business.”
As an investor, you can’t have an opinion on everything. If you have an opinion, you may fool yourself into thinking you actually know something about the subject. Having an opinion does not presume any particular actual knowledge of a subject (see Jenny McCarthy’s on vaccines). Being able to say “I don’t know” separates you from a large portion of the investing world (and the entire staff and most guests on CNBC).