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For women the rules are very complicated:
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The water has to have waves though, the same rules don't apply to say a river or lake; there it would be indecent for a female to remove her top..
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The rules on the Internet are very confusing indeed - one website "Facebook" has declared breasts that do not show nipple are OK, but then they remove pictures of breasts without nipples and leave other nipples on there. I'm not sure whether even they really know what is and isn't OK.
Why the breasts are on show seems to be an important factor. If it's just for fun that seems to be OK, whereas generally they seem to get more upset if the woman is feeding her baby.
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Our culture is infected and obsessed with sexual objectification (thanks to patriarchy).PS the rest of the blog post is well worth a read, just click through the link.
Hence, women's body’s are constantly deemed as being inappropriate when dressed or presented in a certain manner (something that is apparently open to personal interpretation). Men are taught that they’re entitled to our bodies, on many different levels, and women are shamed and blamed when they’re attacked/sexually harassed. [sic]
In fact our culture has gone so far the other way, some suggest exposure to breasts can cause all sorts of problems.... (click the link to see more!) and some consider a picture like that on the link disgusting Well no actually the text with the image discusses nudity, and the writer appears to be discussing discussing genitals (confused? I was!) ....I'm not sure what they were up to during biology class, but my money isn't on listening.
Perhaps most interesting of all, is whilst many Americans feel:
"Increasingly, in the United States, women are pressed to wear burkas. Such level of submission and servitude is un-American, and undermines women's rights to equality and better quality of life" (Facebook group - Americans againt Burkhas)
Nobody considers breast coverage to be vaguely comparable. Nobody argues for equality on the old chest front. Nobody spots the irony....