David Grossman on Characterization

I recently read (and reviewed) David Grossman's Writing in the Dark, a collection of essays mostly about literature and a little about politics. I loved the collection, and I'd like to share this excerpt on Grossman's view of characterization:

When I write a character, I want to know and feel and experience as many characteristics and psychic arrays as possible, including things that are difficult even to name. For example, the character's muscle tone, both physical and emotional: the measure of vitality and alertness and tautness of his or her physical and emotional being. The speed of her thought, the rhythm of his speech, the duration of pauses between her words when she speaks. The roughness of his skin, the touch of her hair. His favorite position, in sex and in sleep.

Not all of these things will end up in the book, of course. I believe it is best for only the tip of the iceberg, only one-tenth of everything the writer knows about his characters, to appear in the book. But the writer must know and feel the other nine-tenths too, even if they remain underwater. Because without them, what surfaces above the water will not have the validity of truth. When these complementary elements exist in the writer's consciousness, they radiate themselves to the visible aspects and serve as a sounding board and a stable foundation for the character, and it is they that give the character its full existence.

If only all writers were this thoughtful about their characters.