[A writer does two things when he introduces the dimension of memory]. First, your hero's personality and his motivations become clear. Because of the widespread knowledge of modern psychology, the writer cannot ignore motivation. It is no longer enough to describe how a character acts and feels; readers want to know why.
Secondly, the use of memories can become the fine-edged tool of the writer's craft. Memories bridge time and distance, heighten tension, reveal character, sharpen the moment of climax. These are only a few of the technical bonuses we reap when we use the characters' memories to our advantage as storytellers. (p. 18)
Just how much of a character's life...
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