What is realistic?

When I was in high school I took AP English. In one of the classes we read works like Macbeth, Wuthering Heights, Heart of Darkness. They all had very little in common, really. But our teacher insisted they were all works with literary merit. This sparked a discussion of what literary merit really meant. Why was Lord of the Flies in the canon, but not Lord of the Rings?
As a writer, I took the discussion all too personally. Not because it was directed at me, but because it made me question whether, as a person whose writing teetered on the edge of fantasy, science fiction and horror, I wrote anything worthy at all.
This question plagued me further in college, when I took a creative writing course in which we were barred from writing anything not “literary”, and therefore unable to write anything but strict realism. Even happy endings were questioned for realism.
The question shifted imperceptibly in my mind from “am I writing anything worthy?” to “am I writing realistically?” to “what is realistic anyway?” The issue for me stopped being about whether I should give up speculative fiction. For me, works with fantastic elements have been some of the most influential. Of course they touch me in a different way than a piece of realism, but that did, in no way, remove the merit. Point in case is Lord of the Rings, which moves me to tears upon every viewing, and sobs upon reading. Because of the grand scale of the events, the story swept me up more than a slice of life, two character drama. Fantasy and other speculative fiction can reveal greater truths about life for the simple fact that they are not realism, and can therefore speak more frankly than realism in many cases. In adding the element of the fantastic, these separate us from the subject matter enough that we can look at them more objectively than if they are set in our own situation where we come in with our own thoughts and prejudices.
So to those of you who thrive on writing the unreal, take heart, you are are writing something just as important, and on a deeper level, just as “realistic” as literary fiction.