In the latest Humanist Network News, there’s a debate on that topic.

Kaitlin Cottle and Gayle Tyree, both students at the University of Tennessee at Chattanooga, argue that Humanists shouldn’t support porn:
These singular and physically dangerous expectations for female beauty and sexuality that are perpetuated by pornography suggest that the value of women lies in their “use.” If we can recognize that female pleasure in porn (and consequently, society) is marginalized, we can understand how our culture has reduced the identity of women to that of an object. In pornography, this process, called objectification, results in the dehumanization of men and especially women because we no longer identify them by their personality and individuality. Inevitably, this dehumanization results in the attitude that because another person is somehow less than human it is acceptable to commit violence against them.
The role violence plays in pornography trivializes rape, sexual aggression, and other forms of abuse. When we encourage males to include dehumanizing acts in sex and teach women to accept various forms of violence against them as a “natural” part of sexual activity, we are condoning violence against women.
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Once the layers are pulled back, it becomes obvious that pornography brings far more harm to our society than good. Its homogenous representations of beauty and sexual activities have created a narrow sexual aesthetic that women must physically harm themselves to achieve. Worse, it consistently features the degradation and abuse of women, valuing them not as people to be respected but objects to be used and creating a climate in which violence is accepted. These negative actions and attitudes against women make it clear that pornography is against the humanist idea that all people are worthy of safety and respect.
Jennifer Kalmanson of the Washington Area Secular Humanists doesn’t think porn is a problem:
One common feminist fear is that by objectifying women in any sexual way, it makes it easier for men as a group to see women as a group as less than human. While there is some merit to this argument in the sense that male behavior in groups can be dehumanizing of women, especially when there’s alcohol involved. However, it’s the male behavior here that’s offensive, not that they may have in the past viewed porn. Let’s go ahead and condemn offensive behavior simply for what it is: jerks behaving like jerks.
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One might also posit that fear of pornographic fantasy is ultimately a fear of female power–the power of sexual prowess with respect to other women as well as power in the utilitarian sense. Until we’re comfortable, specifically, with the idea that a woman in charge of her life can still fantasize about sex with a full range of imagery available to her, we’ll never be able to accept pornography as anything other than a “poem of male desire,” and an often crude one at that. If we can just get over our fears long enough to take a peek, we might just find an industry in which women are very powerful and which produces media capable of enhancing eroticism between partners.
Feel free to chime in, too.
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Incidentally, I once attended a debate between porn star Ron Jeremy and a guy known as the “porn pastor.” It was surprisingly awesome.