G. K. Chesterton: Doing

Collected Works of G.K. Chesterton : The Illustrated London News, 1905-1907 (1986), p. 191

"The Case for the Ephemeral"
All Things Considered (1908)
Context: I cannot understand the people who take literature seriously; but I can love them, and I do. Out of my love I warn them to keep clear of this book. It is a collection of crude and shapeless papers upon current or rather flying subjects; and they must be published pretty much as they stand. They were written, as a rule, at the last moment; they were handed in the moment before it was too late, and I do not think that our commonwealth would have been shaken to its foundations if they had been handed in the moment after. They must go out now, with all their imperfections on their head, or rather on mine; for their vices are too vital to be improved with a blue pencil, or with anything I can think of, except dynamite.
Their chief vice is that so many of them are very serious; because I had no time to make them flippant. It is so easy to be solemn; it is so hard to be frivolous.

"A Defence of Humilities"
The Defendant (1901)
Context: We all know that the 'divine glory of the ego' is socially a great nuisance; we all do actually value our friends for modesty, freshness, and simplicity of heart. Whatever may be the reason, we all do warmly respect humility — in other people.

Opening lines
The Napoleon of Notting Hill (1904)
Context: The human race, to which so many of my readers belong, has been playing at children’s games from the beginning, and will probably do it till the end, which is a nuisance for the few people who grow up. And one of the games to which it is most attached is called “Keep to-morrow dark,” and which is also named (by the rustics in Shropshire, I have no doubt) “Cheat the Prophet.” The players listen very carefully and respectfully to all that the clever men have to say about what is to happen in the next generation. The players then wait until all the clever men are dead, and bury them nicely. They then go and do something else. That is all. For a race of simple tastes, however, it is great fun.
For human beings, being children, have the childish wilfulness and the childish secrecy. And they never have from the beginning of the world done what the wise men have seen to be inevitable.

Tremendous Trifles (1909), XVII: "The Red Angel"
Paraphrased Variant: Fairy tales are more than true — not because they tell us dragons exist, but because they tell us dragons can be beaten.
The earliest known attribution of this was an epigraph in Coraline (2004) by Neil Gaiman; when questioned on this at his official Tumblr account http://neil-gaiman.tumblr.com/post/42909304300/my-moms-a-librarian-and-planning-to-put-literary, Gaiman admitted to misquoting Chesterton: "It’s my fault. When I started writing Coraline, I wrote my version of the quote in Tremendous Trifles, meaning to go back later and find the actual quote, as I didn’t own the book, and this was before the Internet. And then ten years went by before I finished the book, and in the meantime I had completely forgotten that the Chesterton quote was mine and not his.
I’m perfectly happy for anyone to attribute it to either of us. The sentiment is his, the phrasing is mine.
Paraphrased variant: Fairytales don’t tell children that dragons exist. Children already know that dragons exist. Fairytales tell children that dragons can be killed.
Appeared in Criminal Minds 2007 episode Seven Seconds ( IMDB quote entry http://www.imdb.com/title/tt1103432/quotes?item=qt1184717)
Context: Fairy tales, then, are not responsible for producing in children fear, or any of the shapes of fear; fairy tales do not give the child the idea of the evil or the ugly; that is in the child already, because it is in the world already. Fairy tales do not give the child his first idea of bogey. What fairy tales give the child is his first clear idea of the possible defeat of bogey. The baby has known the dragon intimately ever since he had an imagination. What the fairy tale provides for him is a St. George to kill the dragon. Exactly what the fairy tale does is this: it accustoms him for a series of clear pictures to the idea that these limitless terrors had a limit, that these shapeless enemies have enemies in the knights of God, that there is something in the universe more mystical than darkness, and stronger than strong fear.

Source: The Thing (1929), Ch. IV : The Drift From Domesticity
Context: In the matter of reforming things, as distinct from deforming them, there is one plain and simple principle; a principle which will probably be called a paradox. There exists in such a case a certain institution or law; let us say, for the sake of simplicity, a fence or gate erected across a road. The more modern type of reformer goes gaily up to it and says, "I don't see the use of this; let us clear it away." To which the more intelligent type of reformer will do well to answer: "If you don't see the use of it, I certainly won't let you clear it away. Go away and think. Then, when you can come back and tell me that you do see the use of it, I may allow you to destroy it."
This paradox rests on the most elementary common sense. The gate or fence did not grow there. It was not set up by somnambulists who built it in their sleep. It is highly improbable that it was put there by escaped lunatics who were for some reason loose in the street. Some person had some reason for thinking it would be a good thing for somebody. And until we know what the reason was, we really cannot judge whether the reason was reasonable. It is extremely probable that we have overlooked some whole aspect of the question, if something set up by human beings like ourselves seems to be entirely meaningless and mysterious. There are reformers who get over this difficulty by assuming that all their fathers were fools; but if that be so, we can only say that folly appears to be a hereditary disease. But the truth is that nobody has any business to destroy a social institution until he has really seen it as an historical institution. If he knows how it arose, and what purposes it was supposed to serve, he may really be able to say that they were bad purposes, or that they have since become bad purposes, or that they are purposes which are no longer served. But if he simply stares at the thing as a senseless monstrosity that has somehow sprung up in his path, it is he and not the traditionalist who is suffering from an illusion.

Opening lines
The Napoleon of Notting Hill (1904)
Context: The human race, to which so many of my readers belong, has been playing at children’s games from the beginning, and will probably do it till the end, which is a nuisance for the few people who grow up. And one of the games to which it is most attached is called “Keep to-morrow dark,” and which is also named (by the rustics in Shropshire, I have no doubt) “Cheat the Prophet.” The players listen very carefully and respectfully to all that the clever men have to say about what is to happen in the next generation. The players then wait until all the clever men are dead, and bury them nicely. They then go and do something else. That is all. For a race of simple tastes, however, it is great fun.
For human beings, being children, have the childish wilfulness and the childish secrecy. And they never have from the beginning of the world done what the wise men have seen to be inevitable.

The Innocence of Father Brown (1911) The Sins of Prince Saradine
The Father Brown Mystery Series (1910 - 1927)

The Dagger with Wings (1926)

Illustrated London News (19 April 1930)

'No,' said Father Brown.
The Dagger with Wings (1926)

The Innocence of Father Brown (1911) The Three Tools of Death
The Father Brown Mystery Series (1910 - 1927)

Illustrated London News (23 October 1909)

The Dagger with Wings (1926)

Twelve Types (1903) Charles II

As quoted in Mackay's The Harvest of a Quiet Eye, A Selection of Scientific Quotations (1977), p. 34

The Innocence of Father Brown (1911) The Sins of Prince Saradine
The Father Brown Mystery Series (1910 - 1927)

Source: Utopia of Usurers (1917), pp. 15-17

Source: The Victorian Age in Literature (1913), On Algernon Charles Swinburne Ch. III: The Great Victorian Poets (p. 95)