If siblings grew up apart, never knowing (not in the biblical sense) each other until they met in the same manner strangers would, would the absence of the knowledge of their kinship make it a morally unacceptable? I'd say not.
The problem I see arises when siblings are brought up together. In every family there are degrees of power and influence. An older sibling may pressure a younger sibling, which can have other consequences, such as the younger developing a warped attitude towards the pressure and power-play in that relationship and in their life in general.
Other than that, from my experience with my siblings, we rarely sat down at the dinner-table without starting a fight, which I think is the way it should be.
What does disgust have to do with morality? Personally, it disgusts me even the thought of two guys having sex - I don't really know why, but that's the truth - but I don't have anything against homosexuals. It's the same thing with incestual relationships.
We don't have a moral standard, or some sort of commandments that tells us what's right and what's wrong. And we can't ever have such a standard, because we have different personalities. Some think that it is ok to go and massacre Iraqi children, some - myself included - don't. Hitler was behaving exemplary... by his own standards.
And you guys should stop saying that religion is against incest so that's why some people are against it too. Religion is bullshit and hypocrite and so are the people that follow it. Anyone who has read the Bible knows that you can find incest right at the beginning, in the Genesis. And they say that's how we came to be nearly 7 billion people... by sleeping with our mothers, sisters, etc. Even so, a lot of people don't see it that way... after all, the lord works in mysterious ways. Idiots!
well, mostly religions are against incest, whether hypocritical about it or not. And then knowledge about concentration of bad genes made people even more fearful of incest, which is quite ridiculous, because bad genes are likely to be no more concentrated than good genes. Degrees of outbreeding and inbreeding have changed throughout Homo sapiens history, and is bound to continue to do so. Depending on whomever is holding the reins of power.
Disgust is a very strange sensation. We all have such different triggers, for me, its GWBush and domineering men in general, and women who sell themselves to men, not only prostitutes by the way... and feces in the wrong locations... Disgust is not a common sentiment for me, as in life I steer far clear of those who might disgust me, probably to an extreme... Then there are people who are disgusted by any bodily function and any food that's not mass produced, that confuses me to no end.
....Perhaps if one sibling is very young, and the other quite older, yes. That is the main problem I would have.
I will put it as well if it is a female sibling, being taken advantage of by a male sibling, where she is coursed into it. It's just such dangerous territory--as people who live with one another have so much ability to push one another's buttons and manipulate one another--I can barely stand to hear my sister's exploits, so I can't even begin to put myself in that sort of person's shoes.
What about a boy being lured by his older sister? Is that ok? I hate double standards...
Also would be not only worrying to me but a power/status mismatch.
One odd example I found online once was a 13 year old girl(his cousin) demanding that a boy -older- than her show her how he masturbated(he was 17). No touching was involved and nothing went beyond that. Perhaps if he was younger than her, it could be seen as her taking advantage of him, but he was older and could have easily turned her down/walked away from the situation. I don't know how burly a 13 year old girl can get but even I was never strong enough to force an older male to disrobe, and I'm a large girl.
I hate to put a double standard on that, but if a 13 year old boy demanded a 17 year old girl masturbate for him...she would likely turn him down. But I still don't see a 13 year old likely to be able to overpower a 17 year old/take control/advantage of the situation, unless he's a large 13 year old.
Again, in the situation: they were cousins, not raised together, unlike the question, that deals with siblings, who were(I'm assuming) raised together--being raised together or growing up together adds a whole separate dimension to this question that I can barely begin to tackle.
If that particular 17 year old masturbated in front of his 13 year old girl cousin, that doesn't mean that all the guys would have done the same thing in that situation or in a similar situation.
I think there is at least one 17 year old girl that would accept to masturbate in front of her 13 year old boy cousin, so you can't generalize this either.
I have a different question. Would it be ok if a guy would sleep with his stepsister (they were raised together but they are not blood relatives)? Why/why not? I am asking this question because you said that being raised together or growing up together adds a whole separate dimension to this question. So, if two children (not related) grow up together, is it wrong for them to sleep with each other? I think that growing up together can spice things up; they see each other everyday, they know each other very very well; so, if they find each other attractive, it would be for very strong reasons.
I really can't speak for this. If they were similar or the exact same age I don't have the power/status differential, if they're both consenting adults I can't tell them not to, but it's still something I don't 'condone' so to speak--I would never do it. But I can't tell someone else to -not- do it because they're not taking advantage of someone or forcing themselves on someone, you understand? I am not supporting nor condemning.
It is complicated because I just finished an anthropology class that had an entire section on the incest taboo( http://en.wikipedia.org/wiki/Incest_taboo wikipedia did pretty good with it), which I do believe exists, as every person I was raised with or was classmates with in school(several years in a row), was not, in my mind, a possible mate. If you are raised together it normally places a person in the section marked "family" rather than "mate" for roles in your life. This is seen even in Hunter/Gatherer communities where certain people of the community raise full groups of children together, and they choose exogamy(marriage outside this group) rather than endogamy(marriage inside the group). It is the norm, and the incest taboo on people in the family tends to expand in certain cultures--of course in America, where I live, it extends only to immediate family, Grandparents, Parents, Parent siblings, parent sibling's children, and siblings.
Anyone who chooses a mate from these people likely has something deep in their psyche that is different from your average person, in my mind, and this needs to be examined first before any sort of "go-ahead" for behavior is given by anyone. I am so not the moral emperor by any means but most of humanity and even primates will choose anyone -but- our siblings or relatives to mate with.