His substance abuse and negative outlook on society make his point of view quite jaded and probably not a very reliable source for what is really going on in the world. For all the read knows, the whole book could be a dream world and we, the readers, are supposed to read his story as if it is really happening that way. Having this story told in the first person is also important because the reader never fully knows the thoughts or feelings of the other characters in the book. The only way the reader gets to know the other characters in the book are by how they are portrayed and described by Harry, who might not be the most reliable of sources for getting information on other characters. .
The character of Harry Haller is an extremely round character. In the telling of this story, the reader learns of so many dimensions and of so much depth to his character. Harry is an extremely thoughtful character; maybe a little too thoughtful. He scrutinizes every bit of his life, from his childhood to his day-to-day living. This makes him a round character and the fact that he changes throughout the course of the story, makes him a dynamic character. Whether the whole account of the story is a dream of Harry's or actually happening to him, he goes through a change; his mind has been changed by the end of the story. At the beginning of the story, Harry is a very melancholy, troubled man, who is extremely conflicted by the pains of his everyday existence in the "real"" world, while dealing with his spiritual world at the same time. To the reader, it seems as if Harry goes through a series of changes. In the beginning he is extremely somber and alone and almost reaches to the point of suicide until he meets Hermine. Then after he meets Hermine, he seems to instantaneously change his personality. His way of thinking and his outlook on life has been changed. He all of a sudden has a reason to live, and he now seems to fit in more with society.