PDN (Public Display of Nerdiness)

Like in many nerdy departments, we have professors that talk to themselves in the hallways. Usually he or she is giving the day's lecture to themselves or trying to solve a research problem out loud. I don't find it odd anymore when I see it in my building. Of course, if you are in public, that's a whole other ballgame. I happen to drive by one of these professor's houses yesterday and saw him outside in his yard talking to himself and the cat. He was lecturing about chemistry in public! I think the cat's eyes were glazed over.