My only standard of something too mature for someone is that they won’t understand it. For example, calculus is too mature for people who haven’t had trigonometry. If they don’t understand it then it won’t do them much harm reading it, though it may bore them. If they do understand it, and it isn’t actually immoral, then I don’t expect it to harm them. I don’t see a third case.

I can think of at least one off the top of my head — Komarr. In that particular case it’s a less than positive (indeed, I’d say tragic) portrayal, but it’s important to showing the nature of the relationship between Tien and Ekaterin, and just how far it’s degenerated. And no way would I want a child to read it, but I can think of some adults who ought to read it.

Likewise, I would not be particularly thrilled to know that a child was reading some of my fics, but that’s not because I think there’s anything immoral in them (if I did, I wouldn’t have written them) — just that some of the issues and material are too mature for children.

In any case, I wasn’t talking about forcing pictures or stories on an unwilling child, but about hiding information by, say, keeping children out of chat rooms, mailing lists, or archives. If you can’t say it in front of a child, then you shouldn’t be saying it at all.

I agree on a moral level. But on another level, there are things which children are simply not yet equipped to understand or deal with. I don’t mean that we ought to lie to children about the existence of such things, or refuse to answer their honest questions about them — but if a five-year-old child asks about, say, the Holocaust, I don’t think it would be responsible, or kind, or even helpful to the child to sit him down with a lot of horrifying photographs and gruesome explanations. An adult who wants to know the truth about the Holocaust is capable of assimilating that information, but a child would only be confused and terrified by it.

Likewise, I wouldn’t say there’s anything wrong in an honest account of marital sex if a story calls for it, but would I feel right about exposing a child to such a frank depiction? Personally, I think that information, if requested/needed, would be far better conveyed by means of a child-parent conversation than by handing the child a work of fiction on the subject.