When I was in grade school I had a teacher who made us write stories all the time and she would always say: "Write true." I sign off most of the time with "Write hard, write true" as sort of an homage to her. She's the one that first started encouraging me (that and my step mother who got tired of me telling her stories and gave me paper and her old beat up Remington and told me to write them down and she'd read them later)
Anyway, here is one of my favorite movie scenes with a writer giving advice to a new novelist (who's actually earned his living as a screenwriter, but novels are new.) The writer is Hemingway and the quote about writing true is, in reality, something he did say.
What is your favorite writer's quote?