Why is incest bad?

Um, how is that "appeal to nature"? If it was evolutionarily selected for, it means that individuals who weren't the product of incest were more likely to survive than those who were. That would seem to imply that incest is bad, I think.

edited 11th Jun '11 12:42:00 PM by Linhasxoc

Who said they needed to have kids?

By the same reasoning, individuals who are too altruistic will be weeded out of the gene pool. This implies such altruism is bad.

edited 11th Jun '11 12:51:32 PM by LoveHappiness

Damages familial ties.

Actually, altruism is a weird case. It's been shown that altruistic people not only help those around them benefit, but also have several societal benefits otherwise not available due to how good of terms they are on with most people. Incest, on other hand... well, it lacks a few things that actually make it directly beneficial.

Most people are not that altruistic.. And "extreme" altruism is profoundly unfit.

Still definitely true.

Because what's relevant in genetics isn't relevant in social morality. By that logic, gender roles are completely set in stone because there are things which men and women are absolutely better than one-another at, on average.

Yes intergenerational incest is bad. That doesn't make any individual incestuous relationships bad, which in any case needn't lead to procreating at all.

@Zeal: Not necessarily. There's quite a bit of stuff that can be observed in other animals that imply homosexuality is normal, for example. In most species of insect/arachnids, the female is dominant. There have been instances of male chimps caring for toys in a manner similar to female chimps (which resembles human girls playing with dolls). And so on.

edited 11th Jun '11 1:16:04 PM by DrunkGirlfriend

On the "appeal to nature" debate: I'd like to remind people on both sides that nowadays it's quite easy to have incest without inbreeding. But not without drama.

Yeah, but in human genetics, there are certain things which the male body/psyche is built to do, and certain things that the female psyche are built to do. That doesn't mean that those impulses are right (or wrong, for that matter). They were just necessary for our species to survive before we even knew what they were for.

And on the familial "bonds" thing: again, I don't find this inherently right or wrong. It's basically fire—it can burn you or it can make your life better.

Because children with defects?

Thread hoppers like to hop.

It still applies. I want some proof that incest doesn't hurt the child's genetics.

How about if there is no child?

How about unless there's a hysterectomy or an orchidectomy there's still a chance of a child.

What if they never have sex?

I doubt there's are people who are willing to commit incest but unwilling to have sex with their partner.

Incest is sex.

Also, that.

You do not see many teens get pregnant do you? :P

I'm assuming that's a joke.

[1]

Yes, apart from sex there is intermarriage. But why would somebody marry his relative for the sake of platonic love?

@post118

Just like anyone who is aroused by power trip fantasies is incapable of having sex without being a rapist, right?

But beyond that, there are several things to consider: to begin with, older couples, while often advised on the risks of having children late, are not legally deterred from doing it. Neither are couples who learn of genetic predisposition to any likely genetic diseases their offspring might develop. To begin with, the matter of close relation simply means that you are more likely to share more recessive traits that would normally be more likely to be drowned out by other genes; there's a lot more to the genetics than that, but inherently, there's nothing overly special about breeding with someone related to you, versus someone who might have similar genetic risk factors.

So either the law needs to be changed to control all these groups for being woefully misunderstanding of how genetic risk works, or it is actually a discriminatory law that disallows certain activities based entirely on unrelated reasoning.

As for people citing things such as the Westermark effect, that study itself didn't actually focus on biological relation; it was a study on young children who weren't related, but simply grew up in a similar age group. In other words, the results seem to indicate that we are not deterred from biological relations, but instead from close relations with people with have in our formulative years who are the same age as us. Although to begin with, the Westermark effect was concluded from a case study, which means that it was not the most effectively empirical experiment in the world. A lot of supposedly well known psychological phenomenon are based on shaky evidence; I'd advise seriously looking to where anyone got their information when they start talking about fundamental patterns of human behavior.

Finally, anyone trying to make an appeal to natural tendencies should know that animals inbreed all the time, just like many of them practice homosexuality. That's actually how a lot of the second generations of hybrids like Ligers and Tiglons are born, of parents breeding with their offspring in captivity, without any encouragement on the keepers' part for them to do so.

Not that there's any real debate over changing the matter in today's political circles.