Rape is unwanted sex. Why playing in sexy films or sexy scenes as a professional obligation (i.e., being obliged to have sex with another actor/actress who is NOT necessarily beloved already) is not considered as rape? I mean, being raped by the director or producer, not by the other actor/actress who is him/herself the other victim of this rape? And why this job is considered different from prostitution? What's the position of Human Rights in these regards?

It is a little unclear precisely what you have in mind here. Love scenes in mainstream films most certainly do not require the performance of most sex acts (beyond kissing), and so could hardly constitute rape done by or to anyone. The same can be said as to why this is not prostitution, as there is very little in the way of actual sex performed in such films. Of course, real sex acts are performed in pornographic films, and it may well be that in some instances those performing these acts (or on whom they are performed) have not given their consent.

By the way, I do not agree with your definition of rape. I think consent--rather than whether the sex is wanted--is what is key here. Many loving people occasionally consent to sex even when they don't really want it. I would not call that rape. In some cases I could imagine--which may occur, or even occur rather more often than we might suspect--I would call such cases extraordinary acts of love. After all, loving may involve willing sacrifices of one's own momentary wishes. One may not want sex, but may engage in it for other (even good) reasons.

Nicholas is right that there are good reasons to think that rape should not be defined as "unwanted" sex. Although Stephen Schulhofer titled his book on rape Unwanted Sex, he makes it clear that rape, on his view, is to be understood as sex that is not consensual. There has been, of course, debate among rape theorists over the "right" definition of "rape." The law has long employed a "use of force" definition of rape. Recently, the law (in various US jurisdictions) has been moving toward a disjunctive definition of rape: sexual activity either with the use of force or in the absence of consent. (Some jurisidictions make the latter a less serious crime.) It is not difficult to use the philosophical method of counterexamples to argue (more or less convincingly, depending on one's political leanings) that "unwanted," "forced," and "nonconsensual" sex are not identical. Eric Reitan has written a provocative essay in which he argues that rape is an "essentially contested concept" (in the sense of Gallie); it is in Hypatia (2001). On the issue of what sexual obligations exist between spouses (or others involved in a longstanding relationship), see the last chapter in Alan Wertheimer's Consent to Sexual Relations. An early treatment can be found in St. Paul, 1 Corinthians 7.

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