Is it wrong to fantasize about sex with children? If a pedophile never acts on their fantasies are they still guilty of having evil thoughts, assuming that their abstinence comes out of a genuine desire not to do harm?

So far as I can see, there's nothing wrong with fantasizing about sex with children. There's nothing wrong with fantasizing about anything you like. If that seems crazy, then it's probably because you are thinking that someone who fantasizes about something must actually wish to do that thing. But that is just not true. As Nancy Friday makes very clear in My Secret Garden, her classic and groundbreaking study of female sexual fantasy, fantasy is not "suppressed wish fulfillment". The point runs throughout the book, which you can find on archive.org, but maybe the best statement is on pp. 27-8, though see also the poignant story that opens the book (pp. 5-7). I'd post an excerpt, but the language maybe isn't appropriate for this forum!

As Friday's studies reveal, people fantasize about all kinds of things. Some women fantasize about being raped. It's a very common fantasy, in fact. That does not mean these women actually want to be raped, on any level. As Friday remarks, "The message isn't in the plot---the old hackneyed rape story---but in the emotions that story releases" (p. 117), and the emotions can be very powerful, as with any sort of fiction. People also fantasize about sex with family members and strangers, nuns and priests, aliens and robots, plants and animals, and just about anything else you can imagine, including children. It does not mean they actually want to have sex with their sister, their Father, or a child.

So, in short: It does not make someone a pedophile that they fantasize about sex with children, and such fantasies by themselves do not constitute "evil thoughts". I had a lover many years ago, in fact, who had lots of such fantasies, and I can assure you that she was a wonderful person and the furthest thing from being a pedophile.

It is a different question whether someone who is actually attracted to the idea of having sex with children, who is a pedophile, should or should not engage in such fantasies. But that, I take it, is a question for psychologists who are trained to treat such people, and I am not so trained.

I'm sympathetic to most of what Professor Heck says, if we consider things from a deontological or even a consequentialist point of view, where the relevant consequences are external to the agent. Fantasy does not violate anyone's rights, and fantasy that never motivates action will not result in actions that harm anyone. But I think there is a plausible way of looking at things that would still find fault with fantasizing about having sex with children, and that would come from the aretaic (or virtue-theoretic) way of thinking, according to which the primary bearer of value is to be found in characteristics of agents. One who indulges in fantasies about sex with children is doing something that both reflects--and also perhaps perpetuates and sustains--a certain trait of character that we might think is not entirely wholesome or admirable. To the extent that we can regard one who indulges in such fantasies as having a trait of character that is improvable, we might also think that some attempt to eliminate or at least diminish the inclination to indulge in such fantasies would result in that person having some improvement in character. It may be that habituation can only go so far, and that virtue theorists (such as Aristotle) overrate the extent to which one can habituate better character traits, but it certainly does seem that a virtue theorist could find the character of someone who tends to indulge in such fantasies at least improvable, and this way of looking at things does, I think, put a different face on this kind of case than what Professor Heck has indicated.

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