Literature is any text with which a reader identifies with because something within the text is able to connect with the reader about what it is to exist in the human condition. A text must address issues that reveal something about what it is to exist in this earthly plain. It can do this directly or indirectly. The text does not necessarily have to be set in reality but could be set in other worldly settings. It just has to portray the human condition or themes related directly or indirectly to issues that appear in life. People don't change. The human condition stays the same. The only thing that changes is ideology, technology, and socio-political structures.
By defining literature in such a way, it includes things that are not usually looked upon as literature such as comic books and dime store novels. I don't think that dime store novels are that great to read, but apparently there are people who connect to them. Comic books on the other hand I do accept as literature because in a way they are drama like. In Japan, Manga (Japanese Comic Books) are widely read among all age groups, it's not seen as such a lowly art form as in America. They even have girl's and boy's manga.
I see it as if it were a play. You have your cast of characters, their images are provided. So we are given the way the characters appear. As in a play you don't have to extend your imagination to see what the characters look like. Then you have your text. When you watch a play all you get to experience of the text is the dialogue and the way the actors interact with each other. When you read a comic book the only text that you get is the dialogue and all you see is how the characters interact with each other. Also, in manga (I haven't read many American comic books, so I wouldn't know) there are many themes that come up: human relationships; the nature and different types of love; humanity vs. nature; humanity vs. fate or destiny; coming of age stories; technology vs. nature; playing God; the horrors of War; What it is to be human; individuality vs. community; and many more. The characters in Manga are also flawed. They are not perfect and thus they seem real--even thought they may be fantastic figures--and readers can identify with them. The canon is not the only literature that exists.
Literature is connected to the reader. what a reader brings with them can affect how they interpret the text. If a reader goes to a text feeling that the text they are about to delve into is boring, and they are not interested in even looking at it, then they are not going to get the same results as someone who is excited and eager to delve into the work. So the mind frame of a reader can affect a reading. Also, a reader's background can also effect a reading. Their culture, gender, ethnicity, social position, family situation, and life experience can effect how a reader reads a text. Through reading the text the reader can experience things that they might not be able to experience in life. However, depending on the reader's state of mind at the moment when they are experiencing the text, this can be good or bad. For example I have a friend who was feeling depressed with her life. And she was reading a novel, and instead of being uplifting and pleasurable it made her feel even more depressed with her life because she felt that the way her life was she would never ever be able to have any of the experiences or things that the heroine in the text was able to.
A text is also tied to history. A text can reflex several different types of historical information: The political and social mindset of the time in which the piece was written; the historical moment within the text; the fictionalized history of the text which might be a future setting, an alternate history, or an imaginary worlds history. Only the last of these three categories is contained entirely within the text. For the other two it many be necessary to have to do some research so as to understand what ideologies, and political and social issues are shaping the text. However, this should not be done until after you have examined the text closely to find meaning within the work. After examining the text you take the things that were beyond what you know and research them. For instance I read Henry Fielding's Tom Jones a few years ago just for fun, and I was very confused about what was going on with two factions within the text, the Jacobites and the Hanovers. At that point I had never heard of the Glorious revolution so I had no idea what was going on. But after I did some research everything seemed to make more sense.
Literature teaches as it is read. It doesn't just evoke the passions but it teaches, consciously or unconsciously what it is to be part of humanity. It makes readers think. It can bring out revolutionary ideas and it can calm. It can teach morality and it can teach about other people in the world. It lets people experience things they might never get to experience which is also a learning experience. Also a text may even inspire a reader to learn more about a certain topic.
Literature not only teaches it is also aesthetic. It is a thing of beauty that delights the mind. Even if it's a horror story it still can be considered beautiful in its construction and execution. It gives pleasure to the reader.
A piece of literature also has form. Literature uses literary devices such as symbolism and metaphor and many other things. However, not every piece of literature has the same devices within them. The only constant thing is that every text has themes within them and that every reader could see something different in it.
A good critical paper on a text should look at the text, the context, and the reader's response. All these elements are important to give the text a deeper examination. However, this critical approach is not perfect. It requires a lot of time and an extensive library of resources. Also this is a very complex and ambiguous definition of literature that combines aspects of many different schools of critical thought. It not only widens the definition of what is literature but it also makes criticism of literature a bigger job for the critic because not only is close analytical reading a good thing, but also reader response, the historical content, the form, and the content. All these are important. So literature is something that contains the universal--in the general or the specific--and archetypes. This is why it can be related to. It also is a thing of beauty. But it also has a purpose. Literature is not just what is in the canon.