When I used to teach college literature courses, my students were often reluctant to support their arguments thoroughly with textual evidence because they felt as if they were just stating the obvious. I had to beg them to do it, but even when they complied, I think they were often just humoring me.

And it's true that even as I write this, I'm a little bit fearful that some poor student will take my advice only to have his or her paper returned with "Stop stating the obvious!" scribbled all over it in red ink.

But that probably isn't going to happen. Here's why:

1. The "obvious" isn't always obvious. In fact, most stories that are taught in school didn't make it onto the reading list by being simple and transparent.

For example, you might read Charlotte Perkins Gilman's "The Yellow Wallpaper" and think it's obvious that the narrator is selfish and lazy. Or that she is oppressed by her husband and her brother. Or that she dies in the end. Or that she kills her husband at the end. There are so many different things that can seem "obvious" to different readers of this story that you absolutely have to provide textual evidence for your interpretation. You need to show exactly how the words of the story have led you to believe the things you believe. 

2. Your instructor needs to be sure that what's obvious to her is also obvious to you. So even if you and your instructor completely agree on an interpretation of a story, you need to demonstrate that you were able to figure it out independently. It's kind of like showing your work in math.

3. Quotations don't speak for themselves. If they did, then John Updike would definitely get an A on your paper about 'A&P.' But you probably wouldn't.

4. No matter how many times your instructor has read a story, you still might surprise him by noticing details or nuances he has missed, even though they seemed "obvious" to you. It happens more often than you might think.

5. But maybe your instructor hates surprises. And maybe when you surprise her, she's going to immediately conclude that you're just plain wrong, rather than refreshingly insightful. If you've carefully explained your textual evidence, your instructor can at least consider your argument. But if you assumed the evidence for your point was "obvious," your instructor is probably just going to end up assuming, in turn, that you are making stuff up.

When you explain a quotation you've used, you might not be teaching your instructor anything new about the story. But you might be teaching him or her something new about you -- that you read the story closely, that you thought about it carefully, and that you saw something there. Instructors love that. Really.