Janet Asks: Do all the other main characters struggle with the same MP, but in regard to their own issues?
Answer: Yes. that is how the movie can have multiple story lines but still be about one thing. the principles are the same for a novel or a screenplay.
Janet Asks: I've just bought and read The Moral Premise and learned a huge amount from it. But I'm writing a short romance novel rather than a screenplay...The type of romance novel I'm writing needs two main characters (hero and heroine) but there's no room for an additional significant secondary characters or antagonist. (Each acts as the others' antagonist along with the characters' psychological flaws.) Both hero and heroine have different lessons to learn, so I'm struggling to form the vice and virtue sides of the moral premise.
Answer: Good romantic comedies have two protagonists, the man and woman, who are the antagonists for the other. But there are other characters. Each will have a "reflection" character, and each with have a "nemesis" character. These are like the good and bad angels on their shoulders creating scenes that push the characters one way or the other. Each of these minor characters will have arcs that deal with the same moral premise as the main characters do, but obviously just not in as much depth.
When you say the hero and heroine have different lessons to learn, if those lessons are different sets of virtue and vices, then you have two different stories. Your story will connect better with audiences if the virtue and vice set are along the same continuum for both. See the posts on this blog under the topic of "values" (below and to the right under the Movies & Topics list.)
It is not always possible to squeeze a moral premise into an existing story that violates some of the natural laws of storytelling. I frequently guide students to change their story so it's about one thing, and not dilute the core psychological and moral principle which the story is REALLY about.
Janet Asks: Both characters' lives are out of balance. The heroine focuses on work and has no social life, whereas the hero has made play his priority and isn't into serous relationships. (He's successful in his work so he has no lesson to learn about needing to work harder.) She needs to learn how to have fun while he needs to learn that fun flings won't make him happy. If the story was just the heroine's, then the moral premise would be easier, e.g.: A life totally focused on work brings yearning and and sadness but balancing work with fun brings fulfillment and happiness.' But this doesn't include the hero's issues.Answer: For this to work, you need to change elements of your story. See the posts on Nicomachean Ethics — "Mean Virtue. If your heroine is into work and not play, then the hero would be into play and not work. Don't make them too extreme in those areas, but the bias has thrown their lives (with everything in their lives) out of balance. The purpose of the antagonist in a story is to change the protagonist by obstructing the protagonist's goal. Thus your characters are like iron-sharping-iron.
Janet Asks: Does the the moral premise in story with two main characters (who are both heading towards a happy ending) need to incorporate both arcs?--something along the lines of: 'Both an excessively serious approach to life and an excessively playful attitude lead to unhappiness, but a healthy balance between the two leads to fulfillment and happiness.' Often in romance novels the hero and heroine have similarly opposite flaws as the ones above such as Risk/caution/ or using others/helping others, so I'd love to be able to get the moral premise right for 2 protagonists dealing with opposite issues.Answer: Yes, you got it. This is the Nicomachean Ethic post, precisely.