The monster is described as being much larger than average humans. He was sewn together from parts of dead humans, and because of which, has thread weaving him together. He also has muscle tissue poking out between the stitching. He was living in a time where people could not accept other humans if they were disfigured. This left him alone and abandoned by his creator, who, like others in his society, can not accept differences. He had to try to survive by eating berries, and sleeping underneath trees. Doing all this made him understand himself to be an unwelcome person in society. He then becomes consumed with sadness, and almost guilt because he is not good enough for this creator. He goes and kills members of Victor's family, I feel it is partly wanting attention from Victor, and also because he wanted to get back at Victor for leaving him out alone. The monster may not know this at the time, but he feels abandoned and hurt, he looks for a way to make Victor feel the same thing he is feeling. This could have something to do with Mary Shelley, seeing as she was raised by her father, and a step mother who was cruel. She put the monster into the same situation as herself, possibly because she felt like a monster or an outsider in her own life. The monster is disowned by Victor and then is made to understand that people can not accept him, that he really is a monster.
Between these chapters, we learn a lot about the monster. He lives in a hut, sharing a wall with a family, he watches them and soon learns to understand their language. He becomes intelligent. So intelligent, that he understand knowledge isn't always great, he comes to understand that he is not like anyone else. He was more joyous when he knew nothing. He learns about the past of the family and different countries. On a walk through the woods, he discovers a bag of clothing and books, he learns to read them. Mary Shelley could have reflected her own life into the monster's once again. She had read books her mother wrote, out of curiosity and willing to learn, just as the monster had in her novel.
The monster tries to meet the family, only one accepts him, and the rest chased him out of the house. Unable to gain humans trust, he becomes angry at himself, Victor, and humans in general. This is the point where he murders William, because he becomes aware that he is related to Victor. The monster wants to make Victor feel the pain, and guilt that he went through when Victor abandoned him.
-- Before the monster had become intelligent, he had been very oblivious to what people had thought of him. He had not known about this hatred until he lived in the hut.
