The Role of the Character
Here are some of my ideas. (Bear in mind that these are my definitions and my opinions.)
I focus on character and landscape in my novels. Indeed, I don't write as much to produce plot or illuminate concept as I write in order to follow the stories of certain characters who interest me deeply. After all, if these characters don't interest me, I don't know why they ought to interest the reader.
A character should have a four dimensional existence. S/he should seem to have existed before the story begins (and if the character starts as a child, its parents should seem to have existed before the story begins . . . and so forth).S/he should also have enough "life in time" that s/he should seem to continue to exist after the story ends -- unless the character dies at the end of or during the story, in which case the consequences of that death will continue to have repercussions in the lives of other characters or in the plot (and if a death has no repercussions, that in itself is a comment about the character's life).
A character should be more than the sum of its quirks.
A character should reveal elements of personality through interaction with other characters,not just because the author tells you that s/he has certain traits.
A character has motivation, something s/he wants (or at the least something s/he doesn't want: "I'll never go hungry again!")
A character has a world view which informs the way s/he observes and relates to the world around her.
A character has a physical appearance, of course, and it's usually worth describing(although not in a lump paragraph) -- but only in a rare few cases will that appearance be the most important thing about him.
Characters don't only see and hear, they also experience the world through taste,smell, and touch.
We cast shadows when we walk outside on a sunny day. So should the characters we write.
HOW MUCH OF A LIFE?
I use several "levels" of characters in my novels. By "level" I mean how much time the character spends "on stage" in the book and the depth of portrayal I can afford to give her.
I identify three levels of characters:
2) secondary characters
3) tertiary characters
A primary character is a protagonist, the person the book is about -- or, to put it a different way, a character so necessary to the story that the story couldn't exist without her/him. An antagonist is usually also a primary character, especially if the plot revolves around the conflict between the protagonist and the antagonist.
In Jaran I had two primary characters around whom the plot of the book revolved,Tess and Ilya. They remained primary characters in the two-part The Sword of Heaven (aka An Earthly Crown and His ConqueringSword), but because it was more of an ensemble piece they shared "stage time" (or "screen time" if you prefer) with several other characters who acted sometimes as primary characters and sometimes as secondary characters (Aleksi, Diana, David, Nadine). In The Law of Becoming, Tess and Ilya became secondary characters as the spine of the plot shifted to focus on the stories of Vasha, Ilyana, and Anatoly.
A secondary character has at least three and often four dimensions of existence but s/he is not the pivot or central moveraround which the plot revolves although s/he is vital to the story. A really well drawn secondary character, however, often masquerades as a primary character; if the world and the characters have enough substance, then the novel could arguably be told from the point of view of any of the secondary characters, thus changing the focus of the plot.
One reason some writers write such long books is that their secondary characters getaway from them and start wanting an equal part of the action. This is a sure way to fall into writing multi-volume novels.
Alas, the lot of the tertiary character is to be a spear carrier . . . more or less. But with a little extra thought,a well-done tertiary character can briefly suggest that a real person,with a real life, lurks within, awaiting only time and space to emerge.
As an author you can't afford to give tertiary characters the same amount of attention as you would to primary or secondary characters, even though considering them as you would in real life you realize that they (ought to) have an entire four dimensional existence, that they have stories of their own each one of which would fill an entire novel should you choose to focus on them (although some of the stories might not be interesting or edifying).
As soon as a character becomes simply a vehicle for imparting information and/or moving the plot forward, s/he has is no longer a true character but rather a cardboardcutout being moved by the author's hands in order to serve the plot. I'm guilty of this shortcut myself, but I do believe that with care and attention even the least character, seen in passing as the carriage rolls through the Downtrodden Village, can suggest a life being lived outside the confines of the story.