In class we've talked a lot about things that are defined solely by the abscence of something else. I suggested that J Edgar Hoover likes his white room because he knows that black exists, which only makes his room whiter in comparison--that white only exists because black exists. On page 699, Rosemary is speaking about what it was like when Jimmy left the family. "The trick was, the thing was he was not the center of the family when he was here. She was the center, the still center, the strength. Now that he was gone, she could no longer make herself feel still, or especially central. Jimmy was central now. that was the trick, the strange thing. Jimmy was the heartbeat, the missing heartbeat." Without Himmy, Rosemary feels less sure of herself. Before she had something contrast herself with She was the head of the family and she was the strong parent, because it was in comparison to her husband. When he left, some of her identity left with him, because she characterized herself against her ideas about him.
Absense is also noted on 775- "Sometimes it was hard, with the silent classrooms and the halls so life-less, for Sister edgar to know who she was."
Absense makes the heart grow stronger- but sometimes your community and neighbors also define who you are. Without children to frighten and students to drill, Sister Edgar drifts through the empty school a mere ghost of herself.
So she memorizes The Raven by Edgar Allen Poe, her "namesake poet", and plans for when they return.
What is Sister Edgar without her students?
I definitely was perplexed by her character. I was especially touched by the moment when she is changing and cannot look at herself without her habit on. She is a person who is solely defined by her surroundings. She drifts through the school emptily when not teaching, she cannot view her naked self without shuddering- she has no sense of being without her titles and professions. Just as the earlier comment touched on, she is very black and white.