This one is my favorite and I suspect many people who love writing will love this one:

1. Why did I write? Because I found life unsatisfactory.
― Tennessee Williams

2. I don't know why I started writing. I don't know why anybody does it. Maybe they're bored, or failures at something else.
― Cormac McCarthy

3. All stories are about wolves. All worth repeating, that is. Anything else is sentimental drivel.
All of them?
Sure, he says. Think about it. There's escaping from the wolves, fighting the wolves, capturing the wolves, taming the wolves. Being thrown to the wolves, or throwing others to the wolves so the wolves will eat them instead of you. Running with the wolf pack. Turning into a wolf. Best of all, turning into the head wolf. No other decent stories exist.
― Margaret Atwood

4. What really knocks me out is a book that, when you're all done reading it, you wish the author that wrote it was a terrific friend of yours and you could call him up on the phone whenever you felt like it. That doesn't happen much, though.”
― J.D. Salinger, The Catcher in the Rye

5. Make up a story... For our sake and yours forget your name in the street; tell us what the world has been to you in the dark places and in the light. Don't tell us what to believe, what to fear. Show us belief's wide skirt and the stitch that unravels fear's caul.
― Toni Morrison, The Nobel Lecture In Literature, 1993

6. I write entirely to find out what I'm thinking, what I'm looking at, what I see and what it means. What I want and what I fear.
― Joan Didion

7. Writing a novel is a terrible experience, during which the hair often falls out and the teeth decay. I'm always irritated by people who imply that writing fiction is an escape from reality. It is a plunge into reality and it's very shocking to the system.
― Flannery O'Connor

8. Writer's block…a lot of howling nonsense would be avoided if, in every sentence containing the word WRITER, that word was taken out and the word PLUMBER substituted; and the result examined for the sense it makes. Do plumbers get plumber's block? What would you think of a plumber who used that as an excuse not to do any work that day?

9. The fact is that writing is hard work, and sometimes you don't want to do it, and you can't think of what to write next, and you're fed up with the whole damn business. Do you think plumbers don't feel like that about their work from time to time? Of course there will be days when the stuff is not flowing freely. What you do then is MAKE IT UP. I like the reply of the composer Shostakovich to a student who complained that he couldn't find a theme for his second movement. “Never mind the theme! Just write the movement!” he said.

10. Writer's block is a condition that affects amateurs and people who aren't serious about writing. So is the opposite, namely inspiration, which amateurs are also very fond of. Putting it another way: a professional writer is someone who writes just as well when they're not inspired as when they are.
― Philip Pullman

11. Language is my whore, my mistress, my wife, my pen-friend, my check-out girl. Language is a complimentary moist lemon-scented cleansing square or handy freshen-up wipette. Language is the breath of God, the dew on a fresh apple, it's the soft rain of dust that falls into a shaft of morning sun when you pull from an old bookshelf a forgotten volume of erotic diaries; language is the faint scent of urine on a pair of boxer shorts, it's a half-remembered childhood birthday party, a creak on the stair, a spluttering match held to a frosted pane, the warm wet, trusting touch of a leaking nappy, the hulk of a charred Panzer, the underside of a granite boulder, the first downy growth on the upper lip of a Mediterranean girl, cobwebs long since overrun by an old Wellington boot.
― Stephen Fry (as usual the comedian is dripping with words about writing, we get the point)

12. Here is a lesson in creative writing.

First rule: Do not use semicolons. They are transvestite hermaphrodites representing absolutely nothing. All they do is show you've been to college.

And I realize some of you may be having trouble deciding whether I am kidding or not. So from now on I will tell you when I'm kidding.

For instance, join the National Guard or the Marines and teach democracy. I'm kidding.

We are about to be attacked by Al Qaeda. Wave flags if you have them. That always seems to scare them away. I'm kidding.

If you want to really hurt your parents, and you don't have the nerve to be gay, the least you can do is go into the arts. I'm not kidding. The arts are not a way to make a living. They are a very human way of making life more bearable. Practicing an art, no matter how well or badly, is a way to make your soul grow, for heaven's sake. Sing in the shower. Dance to the radio. Tell stories. Write a poem to a friend, even a lousy poem. Do it as well as you possibly can. You will get an enormous reward. You will have created something.”
― Kurt Vonnegut

13. Writers don't make any money at all. We make about a dollar. It is terrible. But then again we don't work either. We sit around in our underwear until noon then go downstairs and make coffee, fry some eggs, read the paper, read part of a book, smell the book, wonder if perhaps we ourselves should work on our book, smell the book again, throw the book across the room because we are quite jealous that any other person wrote a book, feel terribly guilty about throwing the schmuck's book across the room because we secretly wonder if God in heaven noticed our evil jealousy, or worse, our laziness. We then lie across the couch facedown and mumble to God to forgive us because we are secretly afraid He is going to dry up all our words because we envied another man's stupid words. And for this, as I said, we are paid a dollar. We are worth so much more.”
― Donald Miller

14. Go into yourself. Find out the reason that commands you to write; see whether it has spread its roots into the very depths of your heart; confess to yourself whether you would have to die if you were forbidden to write.

This most of all: ask yourself in the most silent hour of your night: must I write? Dig into yourself for a deep answer. And if this answer rings out in assent, if you meet this solemn question with a strong, simple “I must,” then build your life in accordance with this necessity; your whole life, even into its humblest and most indifferent hour, must become a sign and witness to this impulse. Then come close to Nature. Then, as if no one had ever tried before, try to say what you see and feel and love and lose...

...Describe your sorrows and desires, the thoughts that pass through your mind and your belief in some kind of beauty - describe all these with heartfelt, silent, humble sincerity and, when you express yourself, use the Things around you, the images from your dreams, and the objects that you remember. If your everyday life seems poor, don’t blame it; blame yourself; admit to yourself that you are not enough of a poet to call forth its riches; because for the creator there is not poverty and no poor, indifferent place. And even if you found yourself in some prison, whose walls let in none of the world’s sounds – wouldn’t you still have your childhood, that jewel beyond all price, that treasure house of memories? Turn your attentions to it. Try to raise up the sunken feelings of this enormous past; your personality will grow stronger, your solitude will expand and become a place where you can live in the twilight, where the noise of other people passes by, far in the distance. - And if out of this turning-within, out of this immersion in your own world, poems come, then you will not think of asking anyone whether they are good or not. Nor will you try to interest magazines in these works: for you will see them as your dear natural possession, a piece of your life, a voice from it. A work of art is good if it has arisen out of necessity. That is the only way one can judge it.
― Rainer Maria Rilke

15. I never asked Tolstoy to write for me, a little colored girl in Lorain, Ohio. I never asked [James] Joyce not to mention Catholicism or the world of Dublin. Never. And I don't know why I should be asked to explain your life to you. We have splendid writers to do that, but I am not one of them. It is that business of being universal, a word hopelessly stripped of meaning for me. Faulkner wrote what I suppose could be called regional literature and had it published all over the world. That's what I wish to do. If I tried to write a universal novel, it would be water. Behind this question is the suggestion that to write for black people is somehow to diminish the writing. From my perspective there are only black people. When I say 'people,' that's what I mean.”
― Toni Morrison

16. A man who is not born with the novel-writing gift has a troublesome time of it when he tries to build a novel. I know this from experience. He has no clear idea of his story; in fact he has no story. He merely has some people in his mind, and an incident or two, also a locality, and he trusts he can plunge those people into those incidents with interesting results. So he goes to work. To write a novel? No--that is a thought which comes later; in the beginning he is only proposing to tell a little tale, a very little tale, a six-page tale. But as it is a tale which he is not acquainted with, and can only find out what it is by listening as it goes along telling itself, it is more than apt to go on and on and on till it spreads itself into a book. I know about this, because it has happened to me so many times.”
― Mark Twain

17. I notice that you use plain, simple language, short words and brief sentences. That is the way to write English - it is the modern way and the best way. Stick to it; don't let fluff and flowers and verbosity creep in. When you catch an adjective, kill it. No, I don't mean utterly, but kill most of them - then the rest will be valuable. They weaken when they are close together. They give strength when they are wide apart. An adjective habit, or a wordy, diffuse, flowery habit, once fastened upon a person, is as hard to get rid of as any other vice.”
― Mark Twain

18. The problem, if anything, was precisely the opposite. I had too much to write:
too many fine and miserable buildings to construct and streets to name and clock towers to set chiming,
too many characters to raise up from the dirt like flowers whose petals I peeled down to the intricate frail organs within,
too many terrible genetic and fiduciary secrets to dig up and bury and dig up again,
too many divorces to grant,
heirs to disinherit,
trysts to arrange,
letters to misdirect into evil hands,
innocent children to slay with rheumatic fever,
women to leave unfulfilled and hopeless,
men to drive to adultery and theft,
fires to ignite at the hearts of ancient houses.
― Michael Chabon, Wonder Boys

19. I have advice for people who want to write. I don't care whether they're 5 or 500. There are three things that are important: First, if you want to write, you need to keep an honest, unpublishable journal that nobody reads, nobody but you. Where you just put down what you think about life, what you think about things, what you think is fair and what you think is unfair. And second, you need to read. You can't be a writer if you're not a reader. It's the great writers who teach us how to write. The third thing is to write. Just write a little bit every day. Even if it's for only half an hour — write, write, write.
― Madeleine L'Engle

20. I don’t ask writers about their work habits. I really don’t care. Joyce Carol Oates says somewhere that when writers ask each other what time they start working and when they finish and how much time they take for lunch, they’re actually trying to find out, "Is he as crazy as I am?" I don’t need that question answered.
― Philip Roth

21. I try to leave out the parts that people skip.
― Elmore Leonard

22. Write while the heat is in you. The writer who postpones the recording of his thoughts uses an iron which has cooled to burn a hole with. He cannot inflame the minds of his audience.
― Henry David Thoreau

23. Outlines are the last resource of bad fiction writers who wish to God they were writing masters' theses.
― Stephen King

24. Alcohol makes other people less tedious, and food less bland, and can help provide what the Greeks called entheos, or the slight buzz of inspiration when reading or writing. The only worthwhile miracle in the New Testament—the transmutation of water into wine during the wedding at Cana—is a tribute to the persistence of Hellenism in an otherwise austere Judaea. The same applies to the seder at Passover, which is obviously modeled on the Platonic symposium: questions are asked (especially of the young) while wine is circulated. No better form of sodality has ever been devised: at Oxford one was positively expected to take wine during tutorials. The tongue must be untied. It's not a coincidence that Omar Khayyam, rebuking and ridiculing the stone-faced Iranian mullahs of his time, pointed to the value of the grape as a mockery of their joyless and sterile regime. Visiting today's Iran, I was delighted to find that citizens made a point of defying the clerical ban on booze, keeping it in their homes for visitors even if they didn't particularly take to it themselves, and bootlegging it with great brio and ingenuity. These small revolutions affirm the human.”
― Christopher Hitchens, Hitch-22: A Memoir

Related:
The Art of Great Writing: 60 Writing Tips from 6 All-time Great Writers
125 More Tips from 20 All Time Great Writers

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