Well..... I could say a lot on this subject but I have time for only a few comments.....

I would be as much if not more concerned about the violence than the nudity. I think Americans are becoming more and more hardened to the horror of true violence. Perhaps nudity is not as big a problem as sensuality.

I have often considered not only the nudity in National Geographic but in what is considered "art." How do we know it is "art" and not early pornography? I am just throwing out the question.

In any event the changes in publications such as Playboy and others in the last 20 years or so, prove, in my humble opinion, another hardening of the heart towards pornography. The difference (between such publications as Playboy and NG) was always in the provocative nature of the photographs but now we see increasingly provocative photos in mainstream magazines, mall windows and on billboards in the streets and the ones in Playboy and other such publications that in former days were more of a tease, now leave absolutely nothing to the imagination. You may wonder how I know... because I am confronted by these images on every street corner.

Who even considers modesty? Promiscuity is widely accepted in our culture. What is the point of modesty when the objective is attracting a mate?

Bible passages....1 Peter3, 1 Thess.4:3-8,Romans 1.... many others

When I was about 10 years old my mother returned to college in order to study to become a nurse.  As with all college students (as many of us know all too well), she was required to purchase many costly textbooks related to her subject, and in many of these textbooks were hundreds of pictures and illustrations of various parts of the human body, both internal and external, for the purpose of educating medical students so as to be better nurses and doctors.  In other words, pictures of nude human bodies were created in order to educate and assist people in becoming better at what they planned on doing as an occupation.  When I was about 13 or 14, as with virtually all boys of that age, I began to have a "fascination" with the body of the opposite sex and happened to realize that in my very home were these books which provided me with pictures of such.  Needless to say, I looked at these images for reasons not intended by those who created them.  Because of my adolescent and sinful nature, instead of using those pictures for good, as they were intended, I used them for evil, as they were not intended.  

But here is the question: "What is the difference (if any) between National Geographic and Playboy/Playgirl, etc.?"  The question raised above could just as easily be stated, "What is the difference (if any) between Human Anatomy Textbooks and Playboy/Playgirl, etc.? (actually, the "etc." leaves the question open for such other publications to be included)

The difference, I would say, comes down to authorial (or artistic, or both as in the case of movies) intent.  This is something referred to quite frequently in discussions of biblical interpretation, and this topic of the propriety of nudity certainly qualifies as a matter of interpretation.  The authorial intent of Playboy/Playgirl is to sexually stimulate its readers and have sensual thoughts toward the individual portrayed in its pages.  The authorial intent of the anatomy textbook is to better prepare its readers for the issues related to their area of study, which in this case will very likely result in saving lives.  Biblically speaking, one is meant for evil, the other for good.  Is it possible for the anatomy textbook to be used contrary to the intention of the authors.  Of course, and this is precisely what I did.  But should we ban these pictures and thereby inhibit the good it might do in light of those who might misuse it for evil?  Does the good outweigh the evil, or the evil outweigh the good?  I imagine few would argue that people (or even Christians in particular) should not study anatomy on the basis that it may be misused for evil, else the entire health-care practice would cease to exist.  But this is the logical place where these kind of questions eventually take us.

Where else may this argument apply?  A few years ago I became friends with a woman who was studying at another university to become an art teacher.  Part of her requirement for course completion was to draw a nude human body using a live nude model in the classroom, and she pointed out to me that the human body is one of the most complicated objects which can be drawn.  It was further pointed out that the models chosen were virtually always unattractive and would be no one's first choice for the purpose of becoming sexually excited.  However, it would not be hard to imagine that this exercise could be misused by someone for purposes other than enhancing their skills as an artist (in fact, I am reminded of a "Beavis and Butthead" episode based on this very scenario).  But the question remains, "What is the authorial/artistic intent?"  The intent in this case would be to make better artists, not sexually stimulate the viewer.  Should we ban nude models altogether and inhibit the good it might do in order to avoid the evil some might use it for?

To go one step further, what about those movies which include nudity within the story (such as "Schindler's List", and more recently, "Apocalypto")?  The question again comes down to authorial intent:  How did the nudity involved add to the general story of the film which the writer/director intended to tell us?

In the case of "Schindler's List", as I remember the story, two scenes including nudity stand out in my mind.  The one scene took place at either a ghetto or concentration camp where a German high officer stood at the window of his apartment with his rifle and took potshots at Jews while his female companion is in a nearby bed (topless) complaining that the shots were disturbing her sleep.  The intent of the writer/director in this scene, I would say, would be to demonstrate the sick priorities of these two individuals.  While the German officer is clearly morally depraved as he finds enjoyment out of watching helpless people run from their lives, the woman is just as depraved by the fact that her protest against his behavior is not our of concern for the victims' lives, but rather, out of concern for her sleep.  The partial nudity tells at least two things.  The first is the fact that people usually dress that way only when they feel completely comfortable and at home with their surroundings (hence, the same reason men walk around their house in their underwear).  With this attire (or lack thereof) this woman reveals her at-home-ness with her sick surroundings.  Second, the woman's external beauty is marked out in contrast with her internal ugliness, demonstrated by her greater concern for sleep than for human lives.  While it is a man's first nature to be attracted to such a sight, her physical attraction is outweighed by the unattractiveness of her moral character.  In order to demonstrate the sick situation described by the scene, the viewer is forced to be repulsed by that which should be attractive by nature.

The second scene including nudity was that of the Jewish women being herded into the shower-room to be killed by gas.  The women's heads are shaved and they are shown to be herded like animals.  The point is that these are human beings who have been stripped of everything, including, as the scene goes on, their very lives.

These examples of the authorial intention of including nudity are specific, and I think it is also important to look at the bigger picture: What is the authorial intention of these scenes?  To make us better human beings in the process by helping us recognize the absolute horror of what is portrayed (i.e., attractive yet repulsive women, human beings being treated like animals).  Just as the nudity included in the anatomy textbook was meant to make better doctors and nurses, and the nudity included in the art classroom was meant to make better artists, so the nudity included in a movie such as "Schindler's List" is to make better people in general, people who are aware of our capabilities as morally depraved killers.

"Schindler's List" is, without question, a very extreme film, and I will not try to do the same with other movies (such as "Apocalypto"), though I think my general point has been made.  Can nudity be used for good?  I think so.  Can it be used for evil?  I know so.  How do we tell the difference?  As we do in Biblical studies, by trying to examine the authorial intent.  Should we use caution and discernment in watching movies with nudity, even when the authorial intention is one which is good?  Absolutely, just as an anatomy textbook should not be placed in the hands of every 13 year old boy (and Song of Solomon should perhaps not be used as a devotional by sexually weak unmarried couples).