I believe it was in Stephen Koch's Modern Library Writer's Workshop
that I was first exposed to the notion that nobody, not even the writer, can know a story before it has been told. This is one of those pieces of advice that, while I always thought was interesting, is also something that I never fully appreciated until I saw firsthand how true it really is.
When I was writing the first draft of my novel, I knew pretty much how the story was going to go: I knew the beginning and the setup, I knew the key plot points, and I knew how it was going to end. Over the course of several months, as I went about actually writing it, the spaces in between started to fill themselves in, as of course they are supposed to. Even so, when I was about halfway through the draft itself, there was one moment where I was sitting in an airport, scribbling away halfheartedly with my pencil, when I was suddenly struck with some kind of epiphany, where I just kind of saw how the rest of what I needed to write fit together. It's not that I didn't know (at least roughly) what was going to happen; rather, I just now better understood why my brain had put it all there in the first place.
This is not to say, however, that because I had this magical thought that I suddenly had the perfect course for the rest of my book. I did manage to complete the draft in a frenzy of excitement (which was a wonderful experience, I must say), and when the draft itself was 'done,' I had told my story.
So, yes, now I had told my story; having told my story, I now knew what the story was.
It is from this point that I began my new journey: finding a way to tell that story better. The basic idea is the same, of course, and the plot itself isn't going to change in any drastic sense from what I've already created, but in the telling are the details, and the details are what make the story interesting. I know the story, now, and so now I'm equipped to tell it in a way that is more enjoyable, in a way that makes it a more entertaining read, because I know where it needs to go and (I think) I have a fun way of getting there.
I count myself lucky in that I had an attentive 'test audience' for that first draft. They were helpful enough to validate my idea (by letting me know that I had a story worth telling), and they had their own suggestions which I, in turn, have been working with, seeing what I've already written and then deciding, on my own, how to best tell the story I've already told, again--as if 'for real' this time. It's a very hands-on transformative process.
You can almost draw parallels to telling anecdotes. We all have stories that we tell people, time and again, at parties or gatherings or when you first start getting to know someone--stories about things we've experienced, that we know, and that we want to convey to others. But I'm also sure that all of us, in the course of telling and retelling these anecdotes, quickly refine them in the way that we tell them, and probably have set ways that we phrase certain points of those stories to get across what we think is the best effect in the telling.
That's a lot like what redrafting my novel is like, I think. The only difference is that it's fiction from the beginning, so I can change the 'facts' themselves without cheating. It's still the same basic prinicple, though, of retooling the telling of a story that I (now, at last) already know, just spicing up the right points and leaving out the duller bits so that the audience gets the most out of what I want to tell them.