"As I have admitted, it is very difficult to tell in any given case whether a story is piercing to the unliterary reader's deeper imagination or only exciting his emotions. You cannot tell even by reading the story for yourself. Its badness proves very little. The more imagination the reader has, being an untrained reader, the more he will do for himself. He will, at a mere hint from the author, flood wretched material with suggestion and never guess that he is himself chiefly making what he enjoys. The nearest we can come to a test is by asking whether he often re-reads the same story [...] If you find that the reader of popular romance—however uneducated a reader, however bad the romances—goes back to his old favourites again and again, then you have pretty good evidence that they are to him a sort of poetry." -C.S. Lewis, "On Stories" from Essays Presented to Charles Williams
Over Christmas break, my ten-year-old brother introduced me to something I wished I'd had when I was his age, or perhaps I something I wish I'd had the imagination to discover. There's a small rectangular closet underneath the stairs leading into our basement, too small to be used for anything but storage. Still, dad carpeted and lit it, putting a light switch inside. For years, we used it to store white banana boxes filled with books—old medical school textbooks, homeschool lessons, childhood Bibles, 90's magazines, yellowing photo albums, half-filled diaries—until a severe water leak threatened them. We moved them to another room, leaving the closet-under-the-stairs empty. Eventually, extra comforters and blankets made their way in there, along with a pillow or two.
My brother, who is constantly searching for quality kids books and is on his fourth read-through of the Harry Potter series, is notorious for staying up until the early morning hours reading in his bed with a flashlight. On New Year's Day, I was in the basement watching Rich Rodriguez cuss his way through his last game as Michigan's head coach when I heard the unmistakable click-chhhh of a soda can opening from inside the closet. My brother was in there, on a throne of soft blankets, eating snacks and reading a book from Harry Potter—or Narnia, or the Lord of the Rings, or Redwall, or 100 Cupboards, or whatever series he was presently working through. Much of the time, I see qualities in my youngest siblings I admire. This one I admire deeply.
I've always assumed that reading well was dependent on picking the right kinds of books — like choosing Milton over Orson Scott Card, Shakespeare over Stephen King, The Great Gatsby over Twilight. Of course, that's often true. What you read indicates in great measure the quality of your taste. Some books could be considered well-written, but not necessarily admirable, in the same way we might enjoy AC/DC but no one would argue that it's of better quality than a Wagner opera (this point via).
But in another sense, what you read doesn't matter as much as how you read it (or, in my brother's case, at what age). The reader who savors a story, drinking deeply in its atmosphere and pausing to admire its diction, will be able to say she enjoys the story the way it was meant to be enjoyed. On the other hand, the reader who consumes the story as one consumes a sitcom on television isn't actually relishing the book. Only using it for, as Lewis would put it, a temporary high of excitement.
I can't criticize my brother for reading Harry Potter four times (though I might encourage him to, in time, move on to some more mature literature). There's something about the world that makes him come back to Hogwarts. Certainly by the third time through the series, he was already quite familiar with the particulars of the book's plot.* He's moved on from the surprises. So it hasn't merely caught his attention like a video game; it's resonated deep inside him, stirring something he probably doesn't understand or is even aware of yet. The owls, wands, dragons, warm butterbeer, friendships, sacrifices, and Christian undertones bring him back again and again—not to re-experience the plot, but re-inhabit the world.
Reading, when done well, is an immersive experience that beckons the reader to return—often to the same sorts of (if not strictly the same) places. This is where readers, having their imagination sprinkled, return to get it all-out submerged. You don't have to read the "classics" to experience this (as Lewis asserts—even the "bad books" become to the right person like a "sort of poetry"), but like many others, you will likely find that the greatest works have the purest water.
There is another dimension here: the best readers not only read appropriate books—and read them often—but they read widely too. I'm leery of pastors in my church tradition who brag that they haven't "read any fiction in decades." We certainly wouldn't want them to say the same thing about theology books; why should literature be any different? Pastors who don't exercise their imagination are like weight lifters who only train one half of their body.
Reading, like anything worth doing, takes time and effort—your friends who make fun of your proclivity to spend free evenings with a book (or a Kindle, in my case) notwithstanding. Good readers don't merely enter the fictional woods—they linger.
*When I reviewed the latest Harry Potter movie for our student newspaper, my brother read it and was less than impressed at my mostly-negative assessment. Still: "You were pretty close, Andrew," he told me. "Close to what?" I asked. "The truth."