What Constitutes a Normal Conversation?

During the holidays, I've probably engaged in at least a hundred different conversations, many of which are with people that I am meeting for the first time, friends of friends about whom I know nothing. In many videogames, creating convincing conversational interchanges is considered to be an essential dramatic problem. Another season of small talk has convinced me that this is indeed a real rhetorical challenge for those who want naturalistic exchanges with nonplayer characters in games and simulations. For example, today one conversation began with a discussion of watching people sleep and ended with a discussion of earwax: topics covered in between included religion, politics, sex, and money.