For purely practical reasons we count one human body as one "person." That makes sense for all sorts of legal and economic purposes. But it sure doesn't feel as if I have only one person in my head. It feels like a conversation between two friends.

Scott Adams

While I don't ever feel that way, I understand that many people have such internal verbal or non-verbal conversations with one or more other "selves". These are also common in fiction, probably in part as a literary device, but also probably as a reflection of the author's mind. Hmm, maybe it is worth a poll.