Different Types of Books

I feel that even though these stories are continuous stories of each other, that they are very different styles of books. In the first book the author kept the story to just the characters as mice and never had their faces look like people. In Maus 2 already the author has made the mice to be more realistic and they are more human like. Spiegelman actually shows human faces (42-45) which he did not do in the first novel. I just feel that the second book is slightly different and more of a realistic and emotional story.