From the book:

There are some of us now reaching middle age who discover themselves to be lamenting the past in one respect if in none other, that there are no books written now for children comparable with those of thirty years ago. I say written FOR children because the new psychological business of writing ABOUT them as though they were small pills or hatched in some especially scientific method is extremely popular today. Writing for children rather than about them is very difficult as everybody who has tried it knows. It can only be done, I am convinced, by somebody having a great deal of the child in his own outlook and sensibilities. Such was the author of The Little Duke and The Dove in the Eagle's Nest, such the author of A Flatiron for a Farthing, and The Story of a Short Life. Such, above all, the author of Alice in Wonderland. Grownups imagine that they can do the trick by adopting baby language and talking down to their very critical audience. There never was a greater mistake. The imagination of the author must be a child's imagination and yet maturely consistent, so that the White Queen in "Alice," for instance, is seen just as a child would see her, but she continues always herself through all her distressing adventures. The supreme touch of the white rabbit pulling on his white gloves as he hastens is again absolutely the child's vision, but the white rabbit as guide and introducer of Alice's adventures belongs to mature grown insight.