On the level of high art, in their common efforts to express human truths, relationships, attitudes, and personal visions, children's literature and adult literature meet and sometimes merge, and we wonder then whether a given work is truly for children or truly for grown-ups. The answer, of course, is: for both.

Children's literature is considerably more functional than a good portion of adult literature. If I were cynical, I might say: Children's books are written to be read; adult books are written to be talked about at cocktail parties.
There may be more truth that cynicism in that statement. My impression is that many adult books are written only to shock the reader (a short term goal, since shock quickly turns into boredom) or as calisthenics for the author's ego.
On the other hand, children's literature seems an area where books function as they were meant to; where they amaze, delight, and move our emotions. We can respect and admire any number of current adult books, but I find it hard to love them.

Writing for children can be completely honest in non-cynical ways. In adult books you're required to be cynical. It embarrasses us to say positive things. You can have affection and hope in children's books, but that is out of fashion in adult fiction.

There are some themes, some subjects, too large for adult fiction; they can only be dealt with adequately in a children’s book. In adult literary fiction, stories are there on sufferance. Other things are felt to be more important: technique, style, literary knowingness… The present-day would-be George Eliots take up their stories as if with a pair of tongs. They’re embarrassed by them. If they could write novels without stories in them, they would. Sometimes they do. We need stories so much that we’re even willing to read bad books to get them, if the good books won’t supply them. We all need stories, but children are more frank about it.

When you write children’s literature, you write for different ages.

"There are some themes, some subjects, too large for adult fiction; they can only be dealt with adequately in a children's book.

The reason for that is that in adult literary fiction, stories are there on sufferance. Other things are felt to be more important: technique, style, literary knowingness. Adult writers who deal in straightforward stories find themselves sidelined into a genre such as crime or science fiction, where no one expects literary craftsmanship.

But stories are vital. Stories never fail us because, as Isaac Bashevis Singer says, "events never grow stale." There's more wisdom in a story than in volumes of philosophy. And by a story I mean not only Little Red Riding Hood and Cinderella and Jack and the Beanstalk but also the great novels of the nineteenth century, Jane Eyre, Middlemarch, Bleak House and many others: novels where the story is at the center of the writer's attention, where the plot actually matters. The present-day would-be George Eliots take up their stories as if with a pair of tongs. They're embarrassed by them. If they could write novels without stories in them, they would. Sometimes they do.

But what characterizes the best of children's authors is that they're not embarrassed to tell stories. They know how important stories are, and they know, too, that if you start telling a story you've got to carry on till you get to the end. And you can't provide two ends, either, and invite the reader to choose between them. Or as in a highly praised recent adult novel I'm about to stop reading, three different beginnings. In a book for children you can't put the plot on hold while you cut artistic capers for the amusement of your sophisticated readers, because, thank God, your readers are not sophisticated. They've got more important things in mind than your dazzling skill with wordplay. They want to know what happens next."

A child can accept all kinds of weird-looking creatures and bizarre occurrences in a story because the child understands that stories have different rules that allow for pretty much anything to happen. Adults, on the other hand, struggle desperately with fiction, demanding constantly that it conform to the rules of everyday life. Adults foolishly demand to know how Superman can possibly fly, or how Batman can possibly run a multibillion-dollar business empire during the day and fight crime at night, when the answer is obvious even to the smallest child: because it’s not real.

"Why do you write for children?" My immediate response to this question is, "I don't." ... If it's not good enough for adults, it's not good enough for children. If a book that is going to be marketed for children does not interest me, a grownup, then I am dishonoring the children for whom the book is intended, and I am dishonoring books. And words. Sometimes I answer that if I have something I want to say that is too difficult for adults to swallow, then I will write it in a book for children. This is usually good for a slightly startled laugh, but it's perfectly true. Children still haven't closed themselves off with fear of the unknown, fear of revolution, or the scramble for security. They are still familiar with the inborn vocabulary of myth. It was adults who thought that children would be afraid of the Dark Thing in Wrinkle, not children, who understand the need to see thingness, non-ness, and to fight it.

(How do you distinguish Y.A. books from adult fiction?) Partly voice, but my own personal ethos is that Y.A. requires hope. I’m less stringent on my requirement for hope in books for adults.

Children's books are written to be read, adult books are written to be talked about at cocktail parties

The qualities that make for excellence in children's literature can be summed up in a single word: imagination. And imagination as it relates to the child is, to my mind, synonymous with fantasy. Contrary to most of the propaganda in books for the young, childhood is only partly a time of innocence. It is, in my opinion, a time of seriousness, bewilderment, and a good deal of suffering. It's also possibly the best of all times. Imagination for the child is the miraculous, freewheeling device he uses to course his way through the problems of every day....It's through fantasy that children achieve catharsis.

Children's literature as a literary aberration or at best a minor amusement is a notion held most strongly by people who read the fewest children's books. I think it was Ruth Hill Viguers who compared this attitude with asking a pediatrician when he's going to stop fooling around and get down to the serious business of treating adults.

"I had been reading children's books all my life and saw them not as minor amusements but as part of the whole literary mainstream; not as "juveniles" or "kiddie lit," one of the most demeaning terms in the scholastic jargon.
My belief was, and is, that the child's book is a unique and valid art form; a means of dealing with things which cannot be dealt with quite as well in any other way. There is, I'm convinced, no inner, qualitative difference between writing for adults and writing for children. The raw materials are the same for both: the human condition and our response to it."

When you're old enough to write a book for children, by then you'll have become a grown up and have lost all your jokeyness. Unless you're an undeveloped adult and still have an enormous amount of childishness in you.