Lots of people are utterly convinced they're geniuses , but when you talk to them for more than a few minutes, you can tell the real truth about them. Most people you talk to are just normal, average people, and they usually have interesting lives. However, it seems like every party or social event has at least one person that is the know-it-all . They think they're smarter than everyone else in the room, and they can't help but brag about it. At a recent party, a stranger walked into the event…