At Thursday night’s panel, moderator Andrea Davis Pinkney did not waste much time before asking the three children’s book authors on the panel the inevitable question: what was your favorite book when you were a child?

“Animal Farm,” answered Australian author-and-illustrator Shaun Tan. In response to the raised eyebrows, he explained: his mother had plied her children with books in hope that they would develop a love of letters that she, in her own upbringing, had no chance to cultivate. “She thought it was a children’s book,” he said. “It wasn’t until high school that I realized it was a satire.”

In other words–what makes a book children’s literature is not its content, but the eyes that read it.

Throughout the talk, Tan and the two other panelists, Neil Gaiman and Dutch children’s book author Mariken Jongman, were often posed various forms of the same question–who is your audience? “Bipeds,” Gaiman quipped; his co-panelists, too, stepped gingerly around this perilous pigeonhole. But it became clear, as they mused on their relationships with their readers, that there is something unique about having kids as your audience.

What surprised Tan most when he first started writing for kids was “how much they understood”–kids are a lot smarter than adults in some ways, he said. Gaiman recounted how, at readings, teachers mystified at certain passages in his books would appeal to him for explanation, only to find that their students were already two leaps of intuition ahead of them.

“Adults let wisdom get in the way,” Tan said. “Kids look at things as they really are.”

So when young Tan read Animal Farm as a child, he read, in effect, a different story than adults do.

“What made the deepest impression on me was the lack of resolution,” explained Tan. What happened in the end? Why did the horse go to the glue factory? What did all this amount to? It was what was left unexplained that tantalized Tan the most–made him wonder, in other words.

“As a kid, you understand only about fifty percent of what you read,” said Tan. “I kind of liked that state, actually.”

Wonder–for me, the feeling of wonder was the tonic key of my favorite children’s books (and of just about all my favorite books, ever since I was a wee one). And wonder has always been intimately connected with the verb to wonder–to ask questions for which there are no answers.

Hence the ability to read a book like Animal Farm, misunderstand it, and be completely enthralled. I think Tan is on to something about what appeals to children in literature–it’s not about what you tell, but what you don’t tell. If I were to go back now and read The Lorax –of which I still have many stanzas by heart–I would read it as an environmentalist tract. But when I was a child, I was concerned with more profound and pressing questions. What did the Onceler’s face look like? Where did the swamy-swans end up, anyway? And what was going on behind all those little windows in the Onceler’s factory?

It seems that the spark of Tan’s is that same feeling of open-endedness that he felt so strongly when “misreading” Animal Farm as a child. Reading his acclaimed picture-book The Arrival, it is clear that he is a master of leaving room for the imagination: an immigrant couple makes their way in a city where everything–food, appliances, animals–are whimsical inventions of the imagination. There is no dialogue–here too, the reader must fill in the blank.

“People see in it what they want to see,” Tan said. The trick to writing a good children’s book, he explained, is to strip it down to the bare bones, to the point that the reader, “by being baffled, feels an urgency to explain what’s going on.” The book is only one side of the conversation–in order to be real, to be complete, the reader must “add water”–project their own experiences on it, let their imaginations fill in the gaps. The goal is, he put it simply, to “create a mirrored surface.”

Gaiman, whose The Graveyard Book just won the Newbery medal, has been touring the country doing a videorecorded reading series, reading a chapter per city. He described one moment where he, too, left things open-ended. One chapter was too long, so he stopped in the middle, right at the cliff-hanger. Tumult ensued.

“And it was the best thing ever,” he exulted.