No one does anything without a reason. Even if you sit at home and do nothing it is with a purpose: to do nothing. Therefore it is important that our characters have motivation to do what they do. I remember one of the staple questions in fiction workshops was "Why?" Why is the character doing this? But since we are good writers we don't just want to write, "Jack killed the neighbor because he was mad." We want to show why he did it. The reader should be able to discern a reasonable motivation for a character's action.
Currently, I'm reading "Blood Meridian or the Evening Redness in the West" by Cormac McCarthy. The book is about a band of renegade cowboys who travel through Mexico slaughtering Apaches and Mexicans. It's not a story for the faint-hearted and the violence will make you gag more than once. On the surface it's about the racial hatred and land-ownership disputes in the 1840's and 50's in west Texas.
I thought I understood this basis of the motivation, a sign of the times, hatred between Texas and Mexico. But still the violence (killing women, children and infants; scalping them all) didn't quite seem justified. I felt frustrated and was beginning to feel McCarthy just wanted to write about violence. And then I came to a particular passage last night.
One of the band of "warriors" simply referred to as "the judge", a leader among the men, had a habit of collecting samples of the land they passed through. He would kill birds and stuff them, press leaves of newly discovered plants and sketch the landscape. When one of the others asked him why, he explained:
"Whatever exists, he said. Whatever in creation exists without my knowledge exists without my consent....These anonymous creatures, he said, may seem little or nothing in the world. Yet the smallest crumb can devour us. Any smallest thing beneath yon rock out of men's knowing. Only nature can enslave man and only when the existence of each last entity is routed out and made to stand naked before him will he be properly suzerain of the earth."
He goes on for a little while and sums up thusly, "The freedom of birds is an insult to me. I'd have them all in zoos."
After reading that it came to me. This is all about control and dominance. To these men the Indians and the Mexicans are nothing but something that is beneath them, anonymous creatures. The world will not be theirs until each Apache is discarded and scalped for collection. No life but their own is sacred. In saying all this the judge exposed the motivation for the entire group's actions.
And that is what we are all after, isn't it? Control. To varying degrees, of course. Some of us want to be commanders of our destiny. Some just want to know that they can control where they are sleeping from night to night. So where is your character's sense of control, and how much do they want? Where is your sense of control, and how much do you want?