AMERICAN GODS CONTAINS scenes that I would not want a child to read, mostly because I would not want to explain those scenes to a child who had read them and demanded an explanation.

I do not worry about a ten-year-old picking it up and reading it, though. I think any young reader not ready for it would be bored by it. Kids censor their own reading, and dullness is the ultimate deterrent.

I’VE BEEN A professional writer, earning my living through my words, for thirty years now. I have written books for adults and I have written books for children.

I have written several books for adults that were awarded the Alex Award by YALSA, the Young Adult Library Services Association, for being books for adults that younger readers enjoyed.

I have written books for children that were later republished in respectable editions which adults could buy and read in public without fear of being thought childish.

I have won awards for writing for adults, and awards for writing for children. I published my first book for children, The Day I Swapped My Dad for Two Goldfish, almost fifteen years ago now.

So it is embarrassing to admit that, as I write this, as I read it, and for most of the last five months, I have been trying to work out what a children’s book is, and what an adult book is, and which one I was writing, and why.

I think that in general the key question of what is children’s fiction is answered in the same way as pornography, on the “I know it when I see it” principle. And that is true, up to a point.

But Coraline was only published as a children’s book because Morgan DeFiore lied.

Her mother, Merrilee Heifetz, has been my literary agent for the last twenty-five years, and is the person whose opinion in all matters of books and publishing I trust the most. I sent her Coraline, and her opinion was that it wasn’t a children’s book. It was too scary for children.

“I will tell you what,” I told her. “Why don’t you read it to your girls? If they’re scared by it, we’ll send it to my adult editor.” Her girls were Emily, aged eight, and Morgan, aged six.

She read it to them, and they loved it, and they wanted to know what happened next. When she got to the end she called me and said, “They weren’t scared. I’m sending it to Harper Children’s.”

Some years later I was sitting next to Morgan DeFiore, who was then about fifteen, at the off-Broadway opening night of a Coraline musical. I told my now-wife, Amanda, the story, and explained that it was because Morgan was not scared that Coraline was a children’s book. And Morgan said, “I was terrified. But I wasn’t going to let on that I was scared, because then I wouldn’t have found out how it ended.”

IN THE LAST year I’ve written three books.