I'm fairly sure most (all) of us feel parent/child incest is wrong, and for fairly obvious reasons.
However, if a brother and sister are very careful about pregnancy prevention or, better, one or both of them is unable to conceive, what would be wrong with it?
BTW, I'm NOT trying to decide whether to do it with my sister (LOL). This is just a question that came to mind while in a discussion with another person.
The only issue seems to be a species risk but the original question eliminated that as an issue. There seems to be no logical reason against it. Even the genetic factor isn't that critical - consanguinity only increases the risk of perpetuating existing genetic abnormalities and does not introduce new ones. In fact normal relations do the same but are only better at masking the expression - and even that isn't reliable. Given that any species starts with a small gene pool and a limited number of mates to say evolution would select against it would be absurd. A species might develop the trait later on and it might have an advantage that will cause it to be selected for, but that particular one can only thrive if the population has expanded to the point where it no longer eliminates all possible mates. And if such develops it would still have to appear when the population is small enough for it to be distributed to any significant degree to begin with. That trait would require an effective and stable kin-recognition mechanism as well as the aversion to such sexual relations. It would also have to have a mechanism to narrow the distribution of germ cells to non-relatives. Given that multiple aquatic species just depend on the males (and sometimes the females) just blasting their sperm into the waters (and often with multiple males doing it together) without regard to ancestry (and they don't care about it either). They've been doing it for millennia without complication. The genetic issue is a problem but not a show stopper by any means nor is there any definite evidence that it's a normal and automatic evolutionary selection to guard against it. For humans it's a social issue more than an instinctive one. The fact that we even consider the matter at all or even act on the interest is telling. Outside of concerns about social complications there seems to be nothing substantially restricting our conduct other than law and tradition.
Supposedly, we're all related to one African female. In that case, we started out incestuously. Topic for another thread, perhaps.
As a teenager I had an on-off sexual relationship with my first cousin.
Apparently first cousins are considered borderline not-incestuous; some places forbid it as incest and some do not even though they have the concept of incest.
Have you discussed these feelings with your brother/sister then?
The incestuous feelings
ME have incestuous feelings? I don't think so. If you saw me, you'd know my sister wouldn't be interested anyway.
And she shouldn't be. It should go without saying really. Your siblings are there to support, co-exist or even annoy you. Not to build intimate relations with.
But don't we SEEK people to support, co-exist, or annoy? Generally, we call them husbands, wives, or at least significant others. Why couldn't a brother or sister fill that role?
I think the best argument against it is that most people have a trail of terminated sexual relations behind them that they don't want reminders of constantly, which is hardly possible in a family context.
That last is probably the true origin of such taboos. :) Familial ties are complicated enough to deal with already without the extra baggage of unhappy sexual experiences. Though I've read of some cultures ideas of incest that causes me to scratch my head. I have a vague memory of an article about a small group that is known for their promiscuity - even allowing for parent/child & sibling/sibling, but they had a taboo that made me go "huh?". It was something like the mother-in-law of a third cousin or something about as convoluted. Maybe I can trace the tribal group down again but it's been years since I read the article. I think I saw it in the mid-1980s.
Yeah, I see what you are saying but I see my brother as another version of myself. His genetics are so close to mine and I just think a siblings connection is or should be platonic. I can't even imagine how one would first reveal emotional/sexual feelings towards a sibling. 'Normally' we reproduce with the intent that our children aren't going to become 'involved'. Personally, I would be very much against my future childrens' 'relationship' and would probably feel a sense of disappointment in my own choices when bringing them up. I know you can't help who you fall in love with, but surely if you've set out in life with the view that your sibling is your sibling and nothing more, 99.9% of the time it would stay that way. Out of interest though, have you mentioned the idea to your sister? Just to see what her views are on the issue.
I ruled reproduction out from the start. Remember? Let's rule out love as well and just make it sex for sex's sake. They could have a rule amongst themselves to limit themselves to non-coital sexual activities.
I haven't mentioned it to my theistic sister. She's not of a philosophical bent and wouldn't be a good opponent for me. I know how to argue this subject in a platonic way, she probably would not.