The Moral Premise addresses only one small niche of writing, but it covers that niche well.
At some point in our writing journey we each learn that every good story has a psychological subtext--which reveals what the story is really about. Usually, this is the main character's psychological journey and is characterized approximately midway through the story where the main character has his or her "moment of grace", or "ah ha" moment. For example, the moral premise for Bruce Almighty is;
Expecting a miracle leads to frustration,
but being a miracle leads to peace.
The premise is restated throughout the story, and this is what the story is "really" about.
The moral premise sentence sums up what the main character had to learn through the course of the story. The first half of the story showed in numerous ways how his frustration was derived from expecting a miracle. In the second half of the movie, the main character learned through trial and error and at a slow arc that life was great once he chose to be the miracle himself.
The book clears up the difference between Premise and Theme and explains why it is important to know the moral premise when you begin writing. Of course, we don’t live in a perfect world, and at times the writer doesn’t know the moral premise until a later draft.
This book is on my keeper shelf along with what I consider the top ten MVPs of book writing. If you haven’t read this book, I highly recommend it as part of your top ten "how to" books. Better yet, buy the book—study it, and attend this year’s ACFW early- bird session where Doctor Williams will be giving his seminar. I'll see you there.