One way to add depth to your important characters is to determine their philosophies about life. And to maximize conflict, the life philosophies of various characters should contradict each other. (Though it can also be fun to have two characters who believe the same thing, but go about achieving it in conflicting ways.)
I tend to consider my main character's life philosophies quite a bit, but I don't always do a good job considering those of my other characters. In my book The Revised Life of Ellie Sweet, which will be released in the spring of next year, I discovered that my main character's flaw conflicted with another character's life philosophy, and it helped me so much as I wrote the rest of the book.
The main character (Ellie Sweet, as you might assume) has a flaw of taking on the victim mentality. There are a lot of things about her life that she doesn't like, but she defaults to, "That's just how things are."
But Palmer, the boy she likes, believes he has full control over his life. And when I discovered that, it helped me nail down why Ellie is so attracted to him.
This is the scene that ties the two - Palmer's life philosophy and Ellie's flaw - together. They're working in the school's dark room developing pictures, and Palmer has just announced to Ellie (whom he calls Gabrielle) that he's sure he's going to get the lead in the school play:
I roll my eyes, even though he can’t see. “How can you say things like that? Like you know what will happen?”
“Because I’m a man who believes in making my own way.”
“You’re not a man, you’re sixteen.”
Palmer laughs as he clips his picture on the drying line. “You’re hard on a guy’s ego, you know that, sweetheart?”
The room is quiet as I move my picture down the line, a candid of Elliot and my mom in deep conversation. It’s too dark to tell, but I think the photo’s turning out all wrong. As if my bitterness over catching them in that moment, doing something Mom never takes time to do with me anymore, shades everything.
“What did you mean that you believe in making your own way?”
“Exactly what I said. I don’t believe in just sitting back and letting life happen. If I want something, I go get it. I make it work.”
I frown. “That’s ridiculous. You can’t control everything.”
“You can control more that you think.” Palmer stands behind me, boxing me into the corner. “Don’t you get tired of just reading about everything, Gabrielle?”
My blood pressure spikes. “I like reading.”
“But you shouldn’t make it an excuse for not living.”
When you've determined a character's life philosophy, you instantly open the story up for plot lines that show the philosophy as true and false. If Palmer feels he's in control of his own destiny, I'm going to look for ways to show him he can't control as much as he'd like. Yet Ellie needs to be accepting more responsibility for her life, so I'll find plot points that can push her toward taking charge. Make sense?
Make a list of the important characters in your story. What's a sentence or two that describes the way they approach life and choices? What truths do they believe about the universe? In the story, how can those truths seem sound and smart, and how can they seem foolish?
Feel free to share your thoughts in the comments section!