I think both AKA Smith and mysticmom have raised good points during this whole exchange, though my sympathies clearly lie with the former. So let me just make my closing argument here.

Mysticmom, you are demanding a rational explanation for why we believe the depersonalization and commodification of sex is wrong. I'll be honest and say that I can't give you one aside from what I have already said - that the intimate nature of sex suggests that it is an intensely personal and personal act that necessarily involves trust and emotion. If you were to press the issue, I would say that there is no rational reason and that none is needed.

I have studied ethics at length, so this is not some shallow "logic is futile" argument. When dealing with matters of right and wrong action and how they affect others, one can indeed apply objective and rational processes. But these processes will ultimately rely on basic concepts that cannot be further rationalized. For example, Utilitarianism seeks to maximize happiness, but it cannot provide an answer as to why happiness is in itself desirable, perhaps because it's simply defined that way. Similarly, Kantianism relies on concepts such as "human dignity". At a certain point, we are forced to accept some moral concepts as simply axiomatic. Otherwise, one can very rationally say that we are simply collections of particles and thus incapable of doing right or wrong.

"Human dignity" is precisely what is at stake here. Others have pointed out that all kinds of work involves "selling oneself" to some extent, which is true, and is precisely the point that Marx was trying to get across. But prostitution crosses the line of violating the very sovereignty of one's body. And simply because we accept capitalism does not mean we must accept its most brutal extremes. For example, most people do not condone the selling of one's organs, even when done consensually.

You point out that with birth control and protection, our old attitudes towards sex should no longer apply. I would reverse the argument and say that the fact that we still maintain these attitudes despite such changes suggests to me that there may be something intrinsic and "right" about them, like the axiomatic concept of human dignity. Of course, you may counter that an attitude being deeply held does not make it right, perhaps citing racism or sexism as examples. But any argument for how things should be only makes sense when it is somehow compatible with how things already are. Arguments for the abolition of slavery or women's suffrage would not have gained traction had there not existed some previous notions of equality, fairness, freedom, and objectivity.

Ultimately, society will move in the direction that is most consistent with its deeply held beliefs, and only time will tell which of us was right. But it is worth asking again: do you honestly believe that a society in which sex has been stripped of all personal and emotional importance is desirable? Even if the views of society harmonized with the actions of individuals and they felt no shame or scorn, does that always make it right? Consider the society of ancient Greece, where old men took pre-pubescent boys as lovers. The boys did not grow up traumatized or stigmatized as today's victims of molestation do, because it was considered perfectly normal, and all parties were happy. Do we then really have no basis for saying that such an arrangement was wrong, or at least less preferable?

If you are willing to answer yes to all these questions, then I can't argue with you because we are simply working from different assumptions about human nature. I just want everyone who talks about sexual liberation to be fully aware of the logical extent of its consequences. At the moment, such an attitude still seems to go against our intuitions, however clouded they may be. We still see rape as more than just a mere physical assault. We still think there would be something wrong with a girl who let an entire crowd of men gangbang her, even if they all used protection. And we still think sex is somewhat personal.

One final note: I will add again that telling us not to judge someone is confusing their personal right to do as they please with a nonexistent 'right' to be universally approved of. Any society will necessarily take approving or disapproving attitudes towards private conduct, even that which does not directly harm others. That's what makes the difference between a society and a legal system.