Chapter 3-Direct Characterization

In chapter three we first begin to learn of Billy Pilgrim's unstable mental health he has experienced since the war. After Billy fell asleep with a patient during an eye exam Billy, Vonnegut tells us what Billy Pilgrim is thinking when he awakes  from his nap during the appointment by saying "It had been funny at first. Now Billy was starting to get worried about it, about his mind in general. He tried to remember how old he was, he couldn't. He tried to remember what year it was. He couldn't remember that either." From this quote we learn that Billy Pilgrim's mental state of mind is really starting to make a turn for the worst. After he woke from his nap he didn't know how old he was or what the date was. If Billy has forgotten these basic things, I wonder what other important things in his life he has forgotten.