A few of my favorite quotes on writing, from one of my favorite books about writing - Rules of Thumb: 73 authors reveal their fiction writing fixations (edited by Michael Martone and Susan Neville).

"Write before you wake.  Write as you sleep, if at all possible."
Heid E. Erdich, Sleep On It

"Regularity is as helpful with the muse as with the bowels."
John Barth, The Ink-Stained Thumb

"You can start a story with a coincidence, but you cannot end with one."
Michael Martone, Prescriptions/Proscriptions

"Sneaking into an adjacent state and exploding the occasional outhouse won't make you a better writer, but it is true that life lived adventurously will yield unexpected joys or exotic failures."
Stephen Kuusisto, Blow It Up

"You must know the rules.  You must be on friendly, even intimate, terms with them.  That way you can take one aside some evening, slip away for a few drinks, invite the rule back to your place, and then gently and with great tenderness violate the hell out of it."
Jay Brandon, Don't Break That POV, Hand Me the Pliers

"When you die, I believe, God isn't going to ask you what you published.  God's going to ask you what you wrote."
T.M. McNally, Big Dogs and Little Dogs

And one more quote from another source

"If you wrote something for which someone sent you a check, if you cashed the check and it didn't bounce, and if you then paid the light bill with the money, I consider you talented."
Stephen King, Everything You Need to Know about Writing Successfully - in Ten Minutes

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