A game the whole family can play.

January 29, 2005 12:11 AM

If all men were brothers, would you let one marry your sister? Think advocates for gay marriage and group marriage face a lot of social prejudice? Try campaigning for legalizing adult consensual incest. It’s an idea that seems equally distasteful to those on both the right and the left. But what about, say, the very real situation of adoption and sperm donation resulting in meetings between adult siblings who aren’t even aware of the relationship? (Previously discussed here and here.) And then there’s the earnest cousin marriage movement, which makes a lot of people reassess their views on the laws. In fact, the adult consensual incest movement has picked up support from some surprising quarters. Of course, most people are opposed to it, often citing the - quite overexaggerated (PDF) - dangers of inbreeding. (But, of course, this doesn’t explain why they’d still be against adult gay incest, or incest after, say, a tubal ligation.) In the meantime, it is happening, and people are genuinely being arrested for this. Should Montana be sentencing people for up to 100 years for a tryst with a pretty cousin?
posted by kyrademon (91 comments total)

Well, even if its legal we can still make incest jokes right? They can't take that away can they?

Oh and in the first link the woman who cheated on her husband with her dad... It doesn't matter who or [what] she was having sex with its still a deal breaker.
posted by Photar at 1:24 AM on January 29, 2005

Does the fact that many European monarchs were products of incest help or hurt the pro-incest argument? (The link is a little dubious, but it had the best pictures.)
posted by thehippe at 4:26 AM on January 29, 2005

I didn't think it was disgusting when Richie was in love with Margot.
posted by Dean Keaton at 4:26 AM on January 29, 2005

So why are so many people who are pro gay marriage completely skeezed out by kin marriage, polygamy, etc? I know I am.

The pro-incest community is going to be a big impediment to legalizing gay marriage in this country if people think gay marriage is going to open the door to all manner of ickyness.
posted by selfmedicating at 4:43 AM on January 29, 2005

It's not the "offspring may be deformed" thing that bothers me about incest. I can't get my head around a parent being able to do that with their adult child, adopted or biological.
In cases where sperm donations, egg donations and adoptions create two people who meet when they are adults and find themselves sexually attracted to each other, I just don't know what to think. The instant love one has for "own blood" might be confused as sexual attraction, I adore my brother and hate him at the same time (we grew up in the same house and fought over toys after all).
posted by dabitch at 4:47 AM on January 29, 2005

can't get my head around a parent being able to do that with their adult child

Yep. The only principle I can come up with that applies is consent - which is beastialty doesnt seem to be in the same category. Cousins might consent but you can be fairly sure the duck doesn't want to.

Parent/child, even adult child, is extra icky because it potentially involves skewed power relationships.

But still - my whole position on this basically revolves around a gut level "ick" which doesn't seem particularly reasoned, and that bugs me.
posted by selfmedicating at 4:55 AM on January 29, 2005

> The pro-incest community is going to be a big impediment to legalizing gay
> marriage in this country if people think gay marriage is going to open the
> door to all manner of ickyness.

Having seen--not just up close and personal but utterly in-your-face and inescapable--the world generated by sexual liberation, I can't begin to tell you how totally down I am with the idea of a policeman under every bed. Scarlet letters for all of you. (We're long since past the A and the Q, now we're designing the embroidered C for the chicken-fuckers.)
posted by jfuller at 5:08 AM on January 29, 2005

> Cousins might consent but you can be fairly sure the duck doesn't want to.

?? We don't worry about the duck's consent when we kill it and bake it, why would consent be an issue in any less deadly encounter?

The ew factor is entirely sufficient as a reason to forbid. It's to cut down on the occasions when I, accidentally and without warning, have to shake hands with somebody who fucks chickens (or Aunt Betty), which I otherwise wouldn't do without several thicknesses of rubber glove.
posted by jfuller at 5:14 AM on January 29, 2005

Two quick points:

With instances of parent-child incest, one wonders if there has been any sexual grooming of the child by the parent, prior to adulthood. If there are men out there who will have intercourse with their prepubescent daughters, it isn't hard to imagine more patient men who will diligently, and subtly, groom their daughters to become future lovers when they become old enough to legally engage in intercourse.

Secondly, I keep thinking of that X-Files episode with the two brothers and their limbless mother/lover whom they kept under the bed.
posted by Ritchie at 5:19 AM on January 29, 2005

Well, even if its legal we can still make incest jokes right? They can't take that away can they?

"Ain't good enough for family? Ain't good enough for me!"

I keep thinking of that X-Files episode with the two
brothers and their limbless mother/lover whom they kept under the bed.

Ewww!!! I remember that one. I think they were my neighbors at one time. :-)
posted by nofundy at 5:27 AM on January 29, 2005

So why are so many people who are pro gay marriage completely skeezed out by kin marriage, polygamy, etc?

Maybe it's the fear that someone is taking advantage of someone, manipulating someone, trying to gain something by other means, even if they are both old enough to consent under normal circumstances. When a woman has sex with her father or brother or son, for example, you might wonder whether she is doing it to gain or confer some sort of approval or love or security that was missing from the non-sexual relationship with her relative.

Whereas with two gays, assuming there's no other relationship involved (boss-employee, priest-congregant, topbunk-bottombunk, etc.) that might skew things, we assume they are just two adults coming together with mutual attraction, with love, just like the average man-woman couple. Only not.
posted by pracowity at 5:38 AM on January 29, 2005

What pracowity said, essentially. Society looks down on relationships that involve power games in general and family games are the ultimate power games. Cousins doesn't seem like a huge problem to me, and long lost sibling sort of stuff doesn't bother me that much, either, but I can't imagine any closer family relationships that wouldn't end up being fraught with massive emotional baggage.
posted by jacquilynne at 6:30 AM on January 29, 2005

I have found that my cousin gives great head but the idea of marriage is, well, distasteful.
posted by Postroad at 6:49 AM on January 29, 2005

Can't help noticing that the 'states-which-do/don't-permit-cousin-marriages' map is pretty much the same as the 'red/blue states' map.
posted by 327.ca at 6:51 AM on January 29, 2005

Can't help noticing that the 'states-which-do/don't-permit-cousin-marriages' map is pretty much the same as the 'red/blue states' map.

It has five colors, not two, and CA, NY, TX, and FL are all the same color.
posted by coelecanth at 7:12 AM on January 29, 2005

Good post, kyrademon. Thanks for showing the rest of us five-dollar specials how it should be done.

> I didn't think it was disgusting when Richie was in love with Margot.
I didn't think it was disgusting, but I did think it was boring.
posted by Plutor at 7:24 AM on January 29, 2005

Incest is interesting in that most people think of it not just as a taboo, but a moral taboo. However, it's pretty clear that the taboo is one that is simply borne of disgust, not any sort of rational justification. I get a little queasy when really truly try to imagine incest, but it's a quease I'm not proud of and am displeased with myself for feeling. I don't want to buy into any Leon Kass "wisdom of disgust" whatsoever.

Los of people say that the disgust we have is innate, but that's not obvious - so many things we've thought of as disgusting in the past (interracial marriage, homosexuality) have turned out to be socially inculcated. The taboo definitely evolved for fitness purposes, but that doesn't mean that we have an innate incest-taboo module; we could simply have a "find disgusting what society says is disgusting" module, and social evolution converged upon finding incest disgusting (that is, those societies that had a cultural taboo against incest ended up being more fit and successful than those that had intrafamily hookups). If this is the case (and I kinda think it is), then it's possible that over time, if more and more people will feel as I do and try to squelch their revulsion towards incest, we could have a future in which incest is no less disgusting or normal than interracial marriage is today.

What's funny is that I'm kinda repulsed by such a future, but I can't justify the repulsion, so if my descendents are OK with incest then I guess I'll have to be too.
posted by painquale at 7:49 AM on January 29, 2005

Maybe it's the fear that someone is taking advantage of someone, manipulating someone, trying to gain something by other means, even if they are both old enough to consent under normal circumstances. When a woman has sex with her father or brother or son, for example, you might wonder whether she is doing it to gain or confer some sort of approval or love or security that was missing from the non-sexual relationship with her relative.

Sure, but I don't see why it should be the state's business unless there's a minor involved.

Most people disagree with me and believe that the government should enforce morality. I wish either the Democrats or the Republicans would pick a side on this one. I just can't stomach being a Libertarian.

Also, I have a bevy of very, very hot first cousins, some of whom lived with me when I was in middle school. This may have colored my thinking about this issue.
posted by jewzilla at 8:01 AM on January 29, 2005

[I'm going to frame this is a heterosexual way, but you could easily extrapolate to other cases]

Ohhh... I have a hypothetical. Suppose you're a guy and you're out trying to pick up a girl, and you end up getting two sisters. Twin sisters. You lucky dog, you.

If during the course of sex with you they have sex with each other, is it incest? And do you find it disgusting? Do you find lesbian sex in general disgusting? Would you even begin a menage trois, let alone one with sisters?

I think, if offered the chance, that I might be willing to try a situation like that at least once. But I'm not entirely against consensual incest anyways. I do believe that the risk of birth defects is generally overblown, and that the only concern is a parent-child sexual relationship. You just can't help but wonder in that case whether it is love, or an abuse of power.
posted by sbutler at 8:10 AM on January 29, 2005

So why are so many people who are pro gay marriage completely skeezed out by kin marriage, polygamy, etc?

Incest taboos are one of the very few universals in human society, enough so that some have theorized that the structures of our brains require incest taboos.

The interesting thing, though, is that incest is not universally defined. Cousin marriage is preferred in many cultures. It was pretty standard not to long ago in Europe and the Americas as well. When I was in high school, we looked at an old version of incest laws in Ontario and it included stuff like you can't marry your step-family (mother, father, siblings), which, if we measure incest by blood connection makes no sense at all.


The taboo definitely evolved for fitness purposes

This is almost certainly not true. There have been long periods of evolution with small populations where "incest" in the sense of reproduction with those that are closely related is necessary. Also consider societies that trace decent through only one parent. If you are only a child of your father, then marrying a child of your mother who is not also a child of your father may not classify as incest.

My observation is that incest taboos vary with social structure. In societies where ties to many families are necessary or important, more relationships are incestuous. In some societies where decent is traced through only one parent, fewer relationships are incestuous. (These are not "laws" of human organization or anything, just trends I've noticed) It's not just a matter of who is defined as kin, but what claims various members of a group have on others resources, what the subsistance patterns are etc.
posted by carmen at 8:13 AM on January 29, 2005

Hot cousin monkey love? No problem. I've never understood why there are any barriers. But I'm with all the rest that think parent-child relationships are too much about the power.

The far-fetched scenario where brother meets sister without having been raised together holds no ick factor for me. So I am assuming that personally the only time ick is invoked is when family dynamics decides who sleeps with whom.

For the record: I have 0 hot boy cousins and 1 hot brother.
posted by Secret Life of Gravy at 8:29 AM on January 29, 2005

I think that people are very quick to talk about the whole power games factor here in at least some part as a way to disguise their disgust at the idea of consensual incest, or to render that disgust more palatable (perhaps even to themselves, if they're of a more socially liberal bent). I agree that there is greater potential for such game playing in some relationships than others, and that incestuous relationships could well fall into the former category, however, at some point, I think we have to accept that adults are adults, and it's nobody's business to tell them what they can and cannot do with other consenting adults. And, frankly, I see the fact that people remain prejudiced against consensual incest between adults, even to the point that they want laws against "that sort of thing" to remain in place, as merely a phase in our evolution, not really any different from (as others have pointed out) the way people felt about inter-racial and homosexual relationships in the past (and the way many still feel about such things today). Just as wider public acceptance of homosexual relationships as normal and valid and acceptable hasn't resulted in all kinds of otherwise heterosexual people catching teh gay, so wider acceptance of consensual incestuous relationships will do no harm to anyone. People should focus their protective efforts on children and other at-risk individuals, and people who are actually being coerced and leave consenting adults alone.

I do, personally, find the idea of most incestuous relationships somewhat icky, but that's my problem, and I suspect if I actually knew anyone in a consensual incestuous relationship, I'd find it a lot less offputting than the likely highly inaccurate idea I have in my head.
posted by biscotti at 8:33 AM on January 29, 2005

Parent-child incest disgusts me, but I think that is largely because of the inherent power-play. The parent-child relationship is so fraught with power dynamics to start with that to add a sexual element is really going to create something messed up.

Incest in general is less upsetting, but I think the taboo is a good thing because it gives us room to guarantee some non-sexual intimate relationships, which I think is a benefit for all. Sex can add a level of selfishness to a relationship, and especially in cases where you're the beloved more so than the lover, it can take away from the depth of a connection to introduce physical gratification. Or, it needn't necessarily take away, but it will certainly complicate matters.

Additionally, breaking up with someone with whom you've had a sexual relationship often results in a destruction of the relationship altogether. Perhaps the incest taboo serves to stabilize family relationships somewhat.

Of course, these days you can 'divorce' your parents, and more people seem to think trying to stay in touch with an ex is doable and positive, so these general cultural dynamics may evolve.
posted by mdn at 8:40 AM on January 29, 2005

The taboo definitely evolved for fitness purposes

This is almost certainly not true.

Almost certainly? I'm dubious. Incest does seem to lead to decreased fitness (witness the hemophilia of the Russian nobility), and evolution tends to pick up on any phenotypic phenomenon that leads to increased fitness, however slight.

There have been long periods of evolution with small populations where "incest" in the sense of reproduction with those that are closely related is necessary.

Right, and in those populations, incest would be selected for. In large populations, it would be selected against. Those individuals acting incestually would be weeded out. (This is, incidentally, why I think that the taboo is probably best considered a product of social evolution than genetic evolution. If the brain is highly plastic, then it's relatively easy for a new generation to pick up new norms, and behavioral dispositions of a species can adapt in a very short period of time).

Of course, even if incest has been selected against, that shouldn't in the least color our normative judgments of the act.
posted by painquale at 8:42 AM on January 29, 2005

The ew factor is entirely sufficient as a reason to forbid.

my whole position on this basically revolves around a gut level "ick" which doesn't seem particularly reasoned, and that bugs me.

Any time I feel "ew" or "ick" but cannot back up the feeling with sound, logical reasoning, I see an opportunity for self reflection and personal growth. I try to figure out why I feel that way and see if it is reasonable. Most of the time it is not. And when it is not reasonable, I try not to let the feelings override my reasoning.

For example, I see two men kissing and I am repulsed. I see two women kissing, and unless they are both very ugly, I am far from repulsed, sometimes (ok, most of the time) even turned on. Now if I just went by the Ick Factor, I'd push for banning male-male relationships but be all for female-female relationships. That is the kind of inconsistency you get from people that allow unexamined feelings rule their opinions and decisions.

Cousin-cousin doesn't ick me so much. Brother-sister quite a bit. Parent-child a whole lot. But upon examination I cannot back those feelings up with reason. Most/all of the "reasons" to ban these relationships I've seen here do not sway me and sound more like justifications. Many of them could easily be applied to gay or inter-racial relationships as well.

So, until I see some good reasons, I'm against laws banning consenting incest.
posted by Bort at 8:47 AM on January 29, 2005

Since nobody else is dropping cultural references yet, I'll dilute the conversation with some. Two of my favorite movies, The Royal Tenenbaums and Lone Star, feature incestuous relationships that receive the filmmakers' blessing--and mine, too. Is it not ick because it's art? Were these situations icky for the rest of you? I generally have a low ick factor, except about parent-child incest (like in one of the worst movies ever made, the Pia Zadora-fest Butterfly).
posted by goatdog at 9:05 AM on January 29, 2005

Incest does seem to lead to decreased fitness (witness the hemophilia of the Russian nobility)

Nope. Incest doesn't make bad genetic things happen. Incest (inbreeding and linebreeding in the animal-husbandry world) makes obvious or amplifies the recessives in the relevant genome.

If one of the recessive traits the original genome has is hemophilia, you get that amplified. If one of the recessive traits is mutant heat-vision, you get that. If one of the recessive traits is being very tall or having green eyes, you get those.

It doesn't make bad things happen. It just amplifies the recessive traits that are already there.
posted by ROU_Xenophobe at 9:27 AM on January 29, 2005

"Cousins doesn't seem like a huge problem to me, and long lost sibling sort of stuff doesn't bother me that much, either, but I can't imagine any closer family relationships that wouldn't end up being fraught with massive emotional baggage."

We're talking here about a consensual thing between free adults; outsider approval is not necessary. I personally disapprove of "traditional" marriage and/or "BDSM", but I gather that's my problem.

As for "being fraught with massive emotional baggage", what relationship is unlikely to be so? E.g., I've found even eating at a restaurant in a black neighborhood can be fraught with the massive emotional baggage of slavery and Jim Crow; should we therefore forbid it? (And no, there is not a significant moral difference between these examples.)
posted by davy at 9:36 AM on January 29, 2005

I'm surprised nobody has mentioned that ancient Egyptian culture had no incest taboo, and in fact, brother-sister marriages were a common way of preserving royal blood. This kinda discredits the argument that the incest taboo is innate.
posted by [expletive deleted] at 9:37 AM on January 29, 2005

It doesn't make bad things happen. It just amplifies the recessive traits that are already there.

Yes, and it's possible that if we all ratchet up our recessive traits, we all augment our deleterious traits so much that it decreases fitness. There's also the loss of genetic diversity to consider. I'm not claiming that this is the case, just that carmen's claim that incest almost certainly doesn't decrease fitness is way, way too premature.

In fact, I think we should treat incest as being adaptive as a null hypothesis. Universals tend to evolve for reasons, and incest taboos are a strikingly global phenomenon even among other animal species (even if there's wiggle room from culture to culture as to what counts as incest). I'd be highly surprised if it wasn't brought about through evolution.
posted by painquale at 9:57 AM on January 29, 2005

If you were a Miwok, the concept of cousin did not exist. The children of your father's siblings were your brothers and sisters, too. The children of your mother's siblings were not related to you, and could be potential mates. In some cultures, a similar system of family reckoning is used, and the non-relative cousins are are preferred mates.

There are very few absolutes in this words. The next time you are repulsed by something absolutely wrong, take some time to think about it.

Let these people marry whoever the frick the want to marry.
posted by teece at 10:19 AM on January 29, 2005

This is another reason any kind of marriage seems a lost cause. For instance, with marriage as a reproductive arrangement it makes sense to forbid incest - but with gay marriage, what's particularly wrong with it? Ugh. In an ideal world there'd be no marriage and just civil unions which don't even implicitly mandate a romantic relationship.
posted by abcde at 10:24 AM on January 29, 2005

Yes, and it's possible that if we all ratchet up our recessive traits, we all augment our deleterious traits so much that it decreases fitness. There's also the loss of genetic diversity to consider. I'm not claiming that this is the case, just that carmen's claim that incest almost certainly doesn't decrease fitness is way, way too premature.

This only applies if incestuous reproduction becomes as or more popular than non-incestuous reproduction, which is extremely unlikely. It also only applies if most people in higher-risk relationships who wish to reproduce eschew genetic counselling.
posted by biscotti at 10:29 AM on January 29, 2005

Upthread the idea is mentioned that there is a rational reason for the revulsion towards cousin-sibling-parent marriage. You can only take this so far, and in some cases it is just flat out wrong to assume so. As far I as I know the upward generational taboos between parents and children are nearly universal -- so maybe you can reason they are out of some fear of manipulation. But you aren't going to prove it, and it is almost certain that at points in our past, humans did not follow this trait.

The cousin-sibling taboos are not rational, and any rational explanation you find for them is after the fact. This is easy to realize by looking at what the word "family" means to people around the world. (Well, OK, they are rational in the sense that following these taboos is part of the culture, and it is rational to perpetuate your culture, but individual choices with in a culture are not so easy label as "right" or "wrong," and to be truly rational about individual choices, you have to think about those choices outside of any cultural context).
posted by teece at 10:33 AM on January 29, 2005

It doesn't make bad things happen. It just amplifies the recessive traits that are already there.

I'm sorry, what?

If the recessive trait is detrimental to the overall health of the individual and is present in the phenotype where it would otherwise be absent, in-breeding most certainly does make bad things happen.

Your genome has many defects, a lot of them acquired after conception (not inherited) because of constant mutations. A lot of these defects also get into your sex cells. Your relatives are predisposed to the same defects as you much more than unrelated people due to lesser genetic variation and same defects inherited from your common parent. The (non-lethal) defects are much less likely to be expressed if your mate has a good copy of a particular group of genes. Therefore, every round of in-breeding reduces your genetic health, the closer your relative, the more dramatically. It's not a matter of benign phenotype traits, it's a matter of critical genes your body needs to do stuff. Even if the offspring of in-breeding is perfectly healthy, their genetic quality has still been reduced at least somewhat compared to two unrelated healthy parents, and their offspring may suffer. I thought this was pretty obvious from basic genetics.
posted by azazello at 10:33 AM on January 29, 2005

So, wait, are we legislating based on eugenics, now? Well, crap; my family tends towards obesity, guess I can't get married. And we're short, too, so we're screwed twice-over.
posted by kafziel at 10:36 AM on January 29, 2005

I am the product of incest. My parents are first cousins. In our particular Asian culture, cousin marriage is fairly common. In some rural areas it is de rigeur. In urban areas, it is still fairly common. In fact, I can think of two recently married first-cousin couples, who went to college in the U.S., who have elected to marry each other, despite parental opposition (in both cases, the mothers did not get along). I can think of a couple of reasons, among others, for cousin marriage in Asian societies: caste-based classifications and restrictions that limit those whom you can marry and the desire to keep property within families. Cousin marriage aside, closer forms of incest (parental- or sibling-incest) are not practiced and carry the same taboo that they do here in the US.

Personally, I believe firmly, that the State ought not to meddle in the consensual sexual proclivities or pecadilloes of citizens. The State cannot have an interest in decreasing deformities or retardation because of the slippery slope to eugenics (besides, that would only be reason for outlawing straight-incest, not gay-incest). As for maintaining healthy relationships within the family, it is no concern of the State, for if it is, then divorce could be discouraged or outlawed, as could disowning or disinheriting one's kin. As for the 'ick' factor: that is a matter of taste, not morality or ethics, and is fundamentally a personal issue that should remain so.

I would like to point out that in the Biblical story, Adam and Eve only had three children, all of whom were boys: Seth, Kane and Abel. For those who believe in Creationism, how did they have children? From a Creationist perspective, it is likely that all humankind is a product of mother-son incest.
posted by Azaadistani at 10:44 AM on January 29, 2005 [1 favorite]

An interesting Catch 22 for the biblical literalists among us: How did all of humanity, spawned from only one man and one woman reproduce without some form of incest? Wouldn't Cain and Seth (Adam and Eve's sons) have to have procreated with their sisters?

Also, in the Antediluvian period, wasn't everyone on the ark related? If they were the sole survivors of the Great Flood (as biblical literalists interpret) how could they possibly have reproduced to fill the globe without cousin-on-cousin, or sis-on-bro action?

Honest questions, not trying to snark.
posted by HyperBlue at 10:46 AM on January 29, 2005

Child-parent and sibling relationships are all too likely to be the result of grooming and/or unequal power. They make me hinky.

All others, I couldn't care less about. Don't involve me, and I won't care.
posted by five fresh fish at 10:50 AM on January 29, 2005

Other than parent/child or sibling rape/power abuse situations I can't see anything wrong with incest. Distasteful personally yes, but then I don't try to place my judgment, or force my morals upon others.
posted by HyperBlue at 10:50 AM on January 29, 2005

I am alarmed by the post synchronicity between myself, fff and Azadistani.

[puts tinfoil hat back on]
posted by HyperBlue at 10:53 AM on January 29, 2005

Speaking of biblical literalists, I am utterly shocked that nobody has tossed Genesis 19 out there, particularly 19:30-38.
posted by ilsa at 10:56 AM on January 29, 2005

I’m thrilled by the reasoned tone of this discussion. You wouldn’t believe some of the things I’ve had said to me . . .

(Anyway, I apologize in advance for the cut-and-pasted links in this post – I’m pressed for time.)

One of the problems with the “incest taboo as evolutionary necessity” argument is that a certain amount of inbreeding can result in genetic benefits as well as potential problems:

http://www.glostercanary.co.uk/gloster.co18.htm - one of many many pages available on the subject.

And while it’s not the norm in the animal kingdom, it certainly does happen:

http://elibrary.unm.edu/sora/Wilson/v110n04/p0562-p0564.pdf

In fact, the trick may be finding a proper balance between inbreeding and outbreeding:

http://www.popbiol.ebc.uu.se/pdf/intr9.pdf (check the conclusion, and also its assumptions)

Meaning that, in fact, the evolutionary impetus may not be to eliminate inbreeding, but to have a certain amount of inbreeding at a small but nonzero level. Meaning that most would avoid incest, and a certain number wouldn’t – which is what we see in animals (including humans.) Evolution isn’t necessarily simple and obvious. And anyway, if it were so hardwired into us by evolution, why would we need laws about it?

But with the laws as they currently are, the inbreeding argument is a bit of a red herring anyway – the laws aren’t against inbreeding, they’re against incest, which are not the same thing (sister-sister incest is just as illegal as brother-sister incest.) The laws forbid far more than inbreeding.

There is some truth to the power dynamic argument, at least in the case of incest between people from the same household (and most incidences of incest are, after all, the nonconsensual rape of a minor, and I’m not going to say they’re not.) But remember we’re talking, in this case, about the decisions of two adults. Plenty of adult relationships have lopsided power dynamics, but that isn’t illegal. Also bear in mind that in many instances of consensual incest, the “household” dynamic is not a factor – cousins, uncle/neice, siblings raised apart – and they’re just as illegal. Again, if that’s what the laws are about, they cover a lot more than they should.

As is probably obvious, I’m very much on the “let adults do what they want” side of things here.
posted by kyrademon at 11:12 AM on January 29, 2005

Universals tend to evolve for reasons, and incest taboos are a strikingly global phenomenon even among other animal species (even if there's wiggle room from culture to culture as to what counts as incest). I'd be highly surprised if it wasn't brought about through evolution.

That there are taboos is universal. That they are widely divergent is not irrelevant. I will summarize some examples:

Nuer: anything less than a 9th cousin is incest
patrilineal: none of mother's relatives are related (thus may be potential partners)
matrilineal: none of father's relatives are related (thus may be potential partners)
Several societies: cross-cousin marriage preferred (father's sister's child or mother's brother's child) but parallel cousins are incestuous (father's brother's child, mother's sister's child).
Ontario 90 years ago: step family was incestuous.


It is important when talking about the possibility of an evolutionary cause of incest to acknowledge that some forms of "incest" contain no genetic relationship.


There is no "incest phenotype" to get selected for or against, and as I and others have pointed out, incest is not inherently bad genetically. Societies with preferences for cross-cousin marriage do not have more genetic problems than societies without. North America, with its willingness to marry 2nd, 3rd, 4th etc. cousins is not genetically inferior to the Sudan.

Also, note that recessive does not equal bad. Five-fingeredness is recessive. O blood-types are recessive. Lots of things that are great for humanity are recessive.

on preview: what Azaadistani said.
posted by carmen at 11:12 AM on January 29, 2005

An interesting Catch 22 for the biblical literalists among us: ... Wouldn't Cain and Seth (Adam and Eve's sons) have to have procreated with their sisters? ... Also, in the Antediluvian period, wasn't everyone on the ark related?

Obviously. But there's a great loophole -- incest wasn't declared a sin until later.
posted by kindall at 11:16 AM on January 29, 2005

(I always want to quote the incest and group-marriage parts of the bible back at people who quote the old testament against gay-rights groups. "All right, you win! I'll stop sleeping with my girlfriend and start sleeping with my dad.")
posted by kyrademon at 11:21 AM on January 29, 2005

If you legislate this stuff, too, then what is there left for society to slide into? We're running out of stuff pretty quickly. After gay marriage, group marriage, incestuous marriage, man-dog marriage, and man-robot marriage, we'll have nothing left.

On a more serious note, is modern dating so hard these days that we need to legalize shacking up with family members? Get out of your sister's bedroom, log off #sexingsiblings, and go meet some girls at a pottery class or something, for the love of fuck. People fall in love every day. Christ. There are lots of hot people to fuck aside from your family members.

I don't even know if I care about if this is illegal or not. It's just fucking disgusting. Cousins and beyond, sure. Whatever. My family is structured in such a way that I've always thought of my counsins as FAMILY, but I really don't care if people fuck their cousins. Mom and son, father and daughter, sister and brother? Fuck, no. I guestion the healthy nature of a family where that goes down. That's not random love-at-first-sight untainted falling in love. That's emotionally layered, complex, dirty falling in love. There is more going on there than just romance.
posted by Kleptophoria! at 11:36 AM on January 29, 2005

There is more going on there than just romance.

That's true of every human romantic relationship, Kleptophoria! There's always more than romance going on.

But more importantly, what you find disgusting is not, and should not, be the measure of what is accepted in the society.
posted by teece at 11:46 AM on January 29, 2005

We all know this is Frank Zappa's fault, right?
Has anyone notified John Lofton?
posted by joe lisboa at 11:52 AM on January 29, 2005

Your last link is excellent, kyrademon. Thanks for posting it, there's lots of in-depth information in there.
posted by azazello at 12:06 PM on January 29, 2005

After gay marriage, group marriage, incestuous marriage, man-dog marriage, and man-robot marriage, we'll have nothing left.

What about woman-dog, woman-robot marriage?
posted by carmen at 12:11 PM on January 29, 2005

what about woman on viola, or man on tiger action?

see , you see, there will be know end to all the sex combos people will be getting up to!!!

omg when will it all end? before you know it we will have interfacial sex a' going on.
posted by nola at 12:33 PM on January 29, 2005

no*
posted by nola at 12:34 PM on January 29, 2005

I think it's interesting that the incest revulsion seems to correspond to sense of familial relation and not genetic relatedness. This makes sense, I think, as we unconsciously realize that a sexual relationship with someone within our family is going to be problematic. (Imagine being stalked by your sibling. What are you goingo to do? Actually, this was a theme on the first season of Six Feet Under.)

I'm also interested in how we can be conditioned (or choose) to see someone as a potential sexual partner or not. It's always been curious to me that, to me, my sister is sexualy neutral—I can tell that she's moderately good-looking, but I can't evaluate her attractiveness beyond that because I either don't have or have blocked my own sense of sexual attraction to her. On the other hand, there's lots of stories of male siblings being attracted to their sisters. Am I right in thinking that most of them involve older sisters and younger brothers? The whole entering puberty and being a hypersexual adolescent male and an older sister being an inescapable sexual presence?

Most parents (and children) similarly "turn off" (or avoid) their sense of sexual attraction to their children (or parents). But some don't. Why?

Sometimes, some of us also do this with close friends, don't we? Turn off the sexual circuitry (in that relationship) so as to avoid potential trouble?
posted by Ethereal Bligh at 1:00 PM on January 29, 2005

I'm too lazy to search up for supporting links right now, but the whole "incest leads to offspring-deformity" argument has been shown to be vastly overstated. Empirical studies have demonstrated repeatedly that the incidence rate of congenital flaws in offspring of incestuous couples is higher but only slightly so, and still marginal. You are far more likely to impair your future children by inhaling second-hand smoke or having a glass of wine while pregnant.
posted by randomstriker at 1:07 PM on January 29, 2005

kyrademon: And anyway, if it were so hardwired into us by evolution, why would we need laws about it?

I talked about this in my post upthread. Social laws, too, are products of evolution. A society with a taboo against incest may produce more fit individuals than a society without that taboo. What could be 'hard-wired' in us is just a disposition to accept incest taboos when they culturally arise. I agree with everything else you say, though.

carmen: It is important when talking about the possibility of an evolutionary cause of incest to acknowledge that some forms of "incest" contain no genetic relationship.

But I'm willing to bet that most do. Perhaps we evolved to be disposed to accept incest taboos when they culturally arise. In populations where incest would have a deleterious effect, laws that prohibit sexual conduct between genetic relations would be selected for. In populations where incest wouldn't cause damage, less stringent taboos would arise, but they'd still arise because we're evolutionarily disposed to have some sort of incest taboo.

Most people who are arguing that incest can't have been selected against are saying things like, "sure, incest can lead to deleterious traits, but there's nothing intrinsically bad about incest", or "sometimes incest taboos aren't applied to genetic relations." It doesn't matter that there are plenty of cases and plenty of cultures where incest doesn't seem to lead to a loss of fitness. All that matters is that, on statistical average, incest reduces fitness. I don't think we know enough about the effects of incest in different populations one way or another to decide this, but the fact that incest taboos are so universal, even among animals, should tip the scales toward incest taboos having been selected for.
posted by painquale at 1:08 PM on January 29, 2005

painquale, disgust of incest is almost certainly a learned behavior. There is no universal incest taboo, at least not on that I'm aware of, and the presence of incest taboos in animals is of little relevance to human societies.

I'd be very interested to know how many people have ever experienced incestuous urges. I bet the percentages are very high. I suspect that essentially everbody goes through a phase where they seriously consider a sibling or a parent as a romantic partner. This might seem obvious but it suggests that, were it not for strict social taboos, incest would be far more common than it is today.

The danger of incest is that it fundamentally erodes all kinship relationships. If there were an element of sexual competition between members of a family the family would quickly break down. The incest taboo probably arises out this basic need to preserve familial integrity.
posted by nixerman at 1:51 PM on January 29, 2005

...and the presence of incest taboos in animals is of little relevance to human societies.

Well, if you believe that then you're begging the question.
posted by Ethereal Bligh at 2:04 PM on January 29, 2005

What question?
posted by selfmedicating at 2:05 PM on January 29, 2005

One of the articles mentions a phenomenon called "Genetic Sexual Attraction" - which hypothesizes that we are programmed to be attracted to people we're related to biologically, even if we haven't been socialized with them. It seems that GSA came about after the fact to explain the attraction of long lost parent-child and sibling pairs who reunite after years of separation and find themselves in the throes of sexual attraction.

I thought this was particularly interesting as what little I've learned in genetics teaches me that "nature favors a mixture" and also that as far as attraction goes, on a biological level, we're programmed to find people with dissimilar immune systems attractive. (I could be wrong on this, but I've heard it from a lot of fairly reputable sources.) On this basis, it seems that incest isn't so much taboo as improbable. Wouldn't your family members be much likelier to have similar immune systems to yours than, oh, anyone else?

On this level, could GSA be explained as a biological fluke wherein someone by way of genetic oddity is rather attracted to those people with more similar immune systems?

Anyway, the theory about dissimilar immune systems makes logical sense to me from an evolutionary perspective as nature is trying to perpetuate the species. It would just make sense that a child born to parents with dissimilar immune systems would have more immunity to disease and thus would be much likelier to survive into adulthood than a child born to parents with similar or identical immune systems.

(Again, I may be wrong. This is mostly hearsay. Feel free to correct me if I'm completely off base here.)
posted by grapefruitmoon at 2:09 PM on January 29, 2005

disgust of incest is almost certainly a learned behavior

I'm not claiming it's not. Check out my first post in the thread. Even if it's learned, (1) it might have been socially selected for, and (2) we might have evolved a disposition to be good at learning it through the Baldwin effect.

There is no universal incest taboo.

Most people who have weighed in on this thread disagree. It's not totally universal, and manifests itself in different forms, but it's incredibly common -- pretty much the standard for societies.

the presence of incest taboos in animals is of little relevance to human societies

This I strongly disagree with. We've carried over all sorts of drives and inclinations from our animal ancestors, including some that manifest themselves in us as very high-level semantic concepts.
posted by painquale at 2:14 PM on January 29, 2005

grapefruitmoon, I've heard that too: people have a tendency to date and marry others who look strikingly similar to their parents. I have no idea why this is so. If it is so, then it may help explain why incest taboos might have evolved - if it's biologicaly advantageous, for some reason, to sleep with people who look like your parents, then you'd want some sort of stopper on having your parents be your sexual ideal. If everyone just slept with their parents, diversity would go down the tubes.
posted by painquale at 2:21 PM on January 29, 2005

As is probably obvious, I’m very much on the “let adults do what they want” side of things here.

Well sure but doesn't this approach ignore the simple reality that not all adults are equally capable of protecting themselves from each other? Do we not have a million laws around this basic problem designed to equalize the power imbalance that exists between people? Why should sexual behavior, where people are in fact hurt and taken advantage of constantly, be left out of the overall picture?

But more importantly, what you find disgusting is not, and should not, be the measure of what is accepted in the society.

Ok, maybe not what one person finds disgusting but perhaps what a large number of people find disgusting? To ignore emotional responses is to suggest there is no meaning to them at all, they're just random and pointless. Since this is known to be a dangerous thing from a mental health perspective for individuals why not for society? Surely emotions are part of human makeup for adaptive reasons worthy of consideration.
posted by scheptech at 2:25 PM on January 29, 2005

grapefruitmoon, I presume you're referring to such things as Claus Wedekind's famous "Sweaty T-shirt" study, which seemed to indicate that women were more attracted to the pheremones of men with immune systems dissimilar to theirs. That's good science, and you're certainly not off base about that.

The problem is, studies like that are often used to further people's prejudices about what they feel *should* be, rather than what is. A study shows an attraction to a difference, and suggests a sound evolutionary reason. But the jump from there shouldn't be to:"therefore incest is unnatural", and it too often is. It should be to: "are people ever also attracted to similarity, and when, and what might be the reason for that." And in fact, there seem to be some sound reasons for keeping outbreeding from going too far, in the links I posted above.

The problem with the argument from pure genetics (unchangeable structures) - for gays, for incest, for any behavior - is that it doesn't make a lot of sense, really. If something happens, it clearly, well, happens, and it is pretty much by definition natural. How can a behavior be unnatural? So if incest is going on, why presume there's no evolutionary reason for it?

Palinquale's argument about *social* evolution does make more sense. Within the range of behaviors offered to humans by their genetics, some are beneficial, some are harmful, and some are either in certain circumstances. Humans are capable, to a large extent, of imposing artificial rules on large groups to modify behavior. These rules sometimes work and sometimes don't, but tend go through a testing process that could be called "evolutionary" to weed out the poor models. Many of them are sucessful for very valid reasons.

But carmen's equally valid point is that there are a variety of these rules structures, many of which have proven more or less successful. So there's nothing absolutely inherent about any of them - they can be changed. In any society, there tends to be an assumption that the way things are is the best (or only) way things can be. But history shows that isn't true.

Palinquale's point might be - ignore social evolution at your peril. Carmen's might be - give too much credence to social evolution at yours.

I apologize if I've mischaracterized anyone's views.
posted by kyrademon at 2:38 PM on January 29, 2005

And on preview, to scheptech -

" . . . doesn't this approach ignore the simple reality that not all adults are equally capable of protecting themselves from each other?"

You are, of course, right, and my own words that you quote are an oversimplification of my real views. Sorry about that. It might parse better as, I believe adults should do what they want without infringing on the rights of others, and I believe that if the current laws on adult incest are designed to protect people from each other, then they are poorly written, overly broad, and do damage to some innocent people it would be better for them to ignore.

". . . maybe not what one person finds disgusting but perhaps what a large number of people find disgusting?"

My problem with that is, the "digusting" emotional response is subject to a lot of change. A lot of people used to think interracial marriage was "disgusting". I want my laws derived from something with a heck of a lot more basis than just that.
posted by kyrademon at 2:48 PM on January 29, 2005

Palinquale's point might be - ignore social evolution at your peril. Carmen's might be - give too much credence to social evolution at yours.

I would generally agree with this, but I think Palinqaule is giving too much importance to the social part. Just look at what the words "family" and "incest" mean to all of the different cultures, and it is obvious that only parts of the incest taboo are universal (if I remember right, mom-pop, and brother-sister).

But, to me, that is neither here nor there. Should we actively imprison people that are consensually breaking a social taboo? I don't think so. Should we disallow them from taking part in the society altogether? No.

But it is very important to not get completely hung up on "culture is right" type of thinking to me, as so much of culture is obviously arbitrary and only tangentially related to some idea of "right."
posted by teece at 2:58 PM on January 29, 2005

Very true, teece. One could argue (although I wouldn't) that priesthood is a poor idea from a genetics standpoint, or that starting a conversation in the men's bathroom violates a social taboo, but I wouldn't go so far as to say that people should be imprisoned for such things. Certainly not for 100 years.
posted by kyrademon at 3:07 PM on January 29, 2005

Kyrademon, that's a very good summary. Thanks!

teece: I think Palinqaule is giving too much importance to the social part

This is probably a fair complaint; I tend to do that a lot. (btw: it's painquale, no L between the A and I). I think that all neural or psychological modules have evolved through the Baldwin effect, meaning that whenever we say that some mental feature is "innate", what we mean is that we've evolved to be really really good at learning it.

I don't see any sort of borderline whatsoever between innateness and cultural learning - both are simply a tendency for the brain to structure itself in a certain way when exposed to environmental features (even the womb is a part of that environment - learning doesn't begin at birth). This means that I'm usually forced into arguing that things we think of as innate (like color vision and sex drives) can be considered learned behaviors, and it tends to sound like I'm overstressing what most people mean by social learning when I'm really just using 'social learning' to mean something slightly different.

But this is neither here nor there.
posted by painquale at 3:15 PM on January 29, 2005

painquale, calling it "social selection" reeks of pseudo-science. Saying that there is "almost" a universal incest taboo doesn't mean anything, in my book. To me you're saying "(almost) every society has a taboo on some form of what could be considered incestuous relationships"--which is not much at all. So, on this point, we'd have to disagree.

Coming from a strictly common-sense place, I'd suggest (1) were it not for strict social taboos incest would be very common (perhaps even widespread) (2) the widespread existence of incest would cause a breakdown within the familial unit destroying kin relationships (3) the breakdown of the familial unit prevents necessary economic activity. In this light, I'd say it's pretty clear why the majority of societies have sought to eliminate elements of sexual competition within the familial unit.

None of this can be used as an argument that consenting adults cannot engage in such behavior. Even if Nature were subtly driving us away from such behavior this wouldn't be sufficient to provide a moral imperative. On the other hand most governments do have a vested (economic) interest in preserving the integrity of families and therefore would be likely to intervene to prevent widespread incest.
posted by nixerman at 3:16 PM on January 29, 2005

There is no universal incest taboo.

Most people who have weighed in on this thread disagree. It's not totally universal, and manifests itself in different forms, but it's incredibly common -- pretty much the standard for societies.

There is no universal incest taboo. There is a universal *presence* of incest taboos.

Whether the universal presence of incest taboos can be said to have caused or been caused by evolution is complicated by the fact that the taboos vary so much. It's hard to say that "incest" as we define it in North America is bad for populations when half the population of the world prefers to marry their cousins (including several groups of our ancestors). However, I will grant you that continued very close inbreeding over multiple generations has often had negative effects (such as in the Russian monarchy, mentioned earlier).

Linda Fedigan says that incest studies among primates are inconclusive. Some bands of some species have been observed to have incestuous sex (although that doesn't, of course, imply that it resulted in successful reproduction--a key component for evolution) and others have been observed to avoid it. Note, however, that this only applies to mother-child relationships and to uterine sibling relationships. It is impossible to tell if siblings of different fathers or father-daughter coupling are taking place.

on preview: this thread is moving faster than my looking through all my old evolution and primate text-books can keep up with. Sorry if this seems out of place.

kyrademon, my favourite story about those evolutionary-psychology studies like the t-shirt one you mentioned is this: one of those studies found that women had a higher desire to engage in sexual activity when the were ovulating. This led to a number of speculations I won't go into, until a researcher not so enamoured with e-p did a study where she asked women when they physically engage in sexual activity. The results: Friday and Saturday.
posted by carmen at 3:22 PM on January 29, 2005

I once knew a girl who's mother and father were brother and sister. When she was born, her fingers and toes were fused, so she required pretty significant surgery just to have functional (albeit disfigured) hands and feet. (She also had a ton of emotional problems, but there could have been any number of causes for that.) So while I could probably intellectualize a defense for non-procreative consensual relationships between adults, I think the incest babies should probably be avoided.

(At least according to my own anecdotal experience. Feel free to chime in with your own positive experiences.)
posted by subgenius at 4:29 PM on January 29, 2005

I want my laws derived from something with a heck of a lot more basis than just that.

Heh, well fair enough, no arg there.

I guess I'm not really sure about the original intent of your post but from a pragmatists point of view I'd say existing incest laws are unlikely to change much in kind. Perhaps the penalties should be moderated, like those for a lot of other things, but I suspect you could go ahead and study the subject for years in minute detail without changing too many minds about whether they're essentially pro or con incest as a socially accepted norm.
posted by scheptech at 4:33 PM on January 29, 2005

Original intent? Probably just to let people look at what the risks really are, what the laws really say, and whether their own opinions and emotions are rooted in sound fact or received wisdom. I do have an opinion on the matter, clearly. And I don't expect laws to change overnight or probably in my lifetime. Sex laws are old and change slowly (still illegal to sell dildos some places), but they do change (Lawrence v. Texas).

One of the problems is that even if you get past many people's initial repulsion with the idea, it's a bit of a minefield. Most incest is nonconsensual and abusive - I have no desire to see that made legal. As subgenius anecdotally points out, very close consanguinity (like brother-sister) actually does increase the incidence of birth defects to some not-well-measured degree. But should that result in jail time? And even if so, why then are laws about incest rather than inbreeding? Should the power dynamics of people who have lived in the same household be an issue in the law, or not? Why? But when you try to talk about the possibility of reexamining the law and what it says, many people react as if you're trying in favor of child rape and mutant babies.

But, anyway, it certainly doesn't hurt to begin the conversation.

As a fun, somewhat irrelevant aside to the evolutionists who have been thoughtfully weighing in here, Charles Darwin married his cousin Emma Wedgewood and had ten bright and healthy children.

"When the principles of breeding and of inheritance are better understood, we shall not hear ignorant members of our legislature rejecting with scorn a plan for ascertaining by an easy method whether or not consanguineous marriages are injurious to man."

- Charles Darwin. (1871)
posted by kyrademon at 5:08 PM on January 29, 2005

The pharaoh mentioned in one of the articles is incorrectly identified. It should have said Akhenaten, not Hatshepsut. Hatshepsut was a female pharaoh from a few generations back (same dynasty). Also, Akhenaten was not the product of a brother-sister couple. Most Egyptologists believe he suffered from Marfan Syndrome. However, Akhenaten did marry at least two of his daughters with Nefertiti.

/OT
posted by deborah at 5:41 PM on January 29, 2005

nixerman: calling it "social selection" reeks of pseudo-science. Saying that there is "almost" a universal incest taboo doesn't mean anything, in my book.

I only put the 'almost' in there because there are no universal traits; there are only traits that are statistically likely to manifest themselves in a certain environment phenotypically . And social selection isn't pseudo-science. If you have any arguments against it, I'd be happy to rebut them.

(1) were it not for strict social taboos incest would be very common (perhaps even widespread) (2) the widespread existence of incest would cause a breakdown within the familial unit destroying kin relationships (3) the breakdown of the familial unit prevents necessary economic activity. In this light, I'd say it's pretty clear why the majority of societies have sought to eliminate elements of sexual competition within the familial unit.

I agree that this could be one possible reason that incest taboos are necessary. There are other possible reasons, too. But the step you make after step three is the one I can't abide: that societies have "sought to eliminate elements of sexual competition within the familial unit," as if this were something rationally done and decreed in order to protect economic interests. I think you're right that it's good for societies to have incest taboos, but it's just utterly unlikely that a council of elders convened somewhere and decided to somehow train youngsters that incest was wrong. (Saying this is like saying that Locke's social contract was literally written out and signed by our forefathers). If societies have all converged upon incest taboos without explicit and conscious human intervention, then some other mechanism must have been in play.

carmen: There is no universal incest taboo. There is a universal *presence* of incest taboos.

OK, I can accept that. I think most of this thread has reached a tentative agreement anyway; kyrademon's summary was pretty spot-on. And his (her?) comment about Darwin is just marvelous!

It looks like the thread is winding down, so: thanks for the discussion, guys! This has been one of the better MeFi threads.
posted by painquale at 8:07 PM on January 29, 2005

kyrademon : I think you misread a bit of what I said. I didn't say that people are always attracted to someone with a dissimilar immune system or that they should be. I was saying that within this framework, GSA doesn't really make sense, so how do you explain it? Because it clearly happens, so how do you reconcile the theory that you're attracted to someone who is or resembles your parents with the theory that you're attracted to a dissimilar immune system, as your family members are the most likely to have a similar immune system?

Oh dear. I'm afraid that in my attempt to clarify myself, I've made even less sense.
posted by grapefruitmoon at 10:25 AM on January 30, 2005

grapefruitmoon -

I wasn't accusing you of making assumptions; merely noting that the problem with such studies is that those assumptions are sometimes made.

I think you've answered your own question, though - the pheremonic signs of a dissimilar immune system are just *one* of the many things people are attracted to, not the only one. People are also attracted to physical symmetry, status, talent, the presence of cultural values, "hourglass" shape in women and other signs of high fertility, etc., etc., etc. There's no reason GSA and immune system attraction can't coexist; they aren't mutually exclusive.

Although it's oversimplifying, one way to think of it is like this - you need drives that encourage a certain attraction to similarity; otherwise, humans would tend to sleep with trees and tigers and stuff and not get very far. You also need drives that encourage a certain attraction to difference; otherwise, you'd only sleep with your parents and "inbreeding depression", the negative effects of long-term large-scale inbreeding, would start to affect the population. In most people, the drives balance out and you end up sleeping with humans not related to yourself. In some people, one or the other drives is so much stronger than the other that either the very exotic or the very similar becomes very attractive - and these people probably also important to the gene pool, since a bit of inbreeding and a bit of extreme outbreeding both can add value to the population as a whole. And there are a few people, like me, in whom both drives are so strong that we'll pretty much sleep with anything, be it a sexy relative or a sexy tree.

It's oversimplifying because there are so many reasons to be attracted to someone (or repelled by someone) that it's hard to tell what's the overriding factor. Whether or not you sleep with your brother isn't just a matter of GSA vs. pheremones - you're also, say, attracted to his symmettry, but repulsed by the "differentiation" factor that seems to affect children raised together, but you find his skill at the guitar arousing, which you crush in your mind because of strong cultural taboos against incest, until his musculature starts sending signals to your reptile brain, but subconsious knowledge of the way a sexual overture could fundamentally change your relationship to him causes you to sublimate your desire into a lust for a rock star who looks a lot like your brother, and so on.
posted by kyrademon at 1:30 PM on January 30, 2005

What nixerman said. Incest taboos have become prevalent in our interlinked, modern societies because promoting exogamy acts as a great mechanism for wealth redistribution. Societies that facilitate familial endogamy tend not to be relatively successful in a post-medieval economic situation.

In a very great way you can trace the evolution of the pre-Renaissance economic conditions to the inadvertent creation of a pan-European merchant class by the Roman Church throughout Europe in the late medieval period following its proclamation of extreme cosanguinity marriage decrees . These defined (and constrained) marriage between relatives out to the 7th degree (later relaxed after several decades to the 4th decree) and had a powerful disruptive effect on the tight kinship economic blocs that had characterised medieval European society and mitigated against the emergence and growth of strong City and State power structures.

Basically, it took the Catholic Church a long time to decide on its preferred balance between Roman and German techniques of kinship evaluation. It was noted by many observers at the time that under the Roman system (~4th degree) pan-European trade and tax systems had propsered, but that under the Germanic systems (~7+ degrees) the ability of the King/State to tax widely and promote wide trade networks had foundered.

it's just utterly unlikely that a council of elders convened somewhere and decided to somehow train youngsters that incest was wrong.

Why do people believe that some of the greatest minds in some of the most powerful organisations of their time were not capable of planning and executing social engineering projects on a huge scale? The 1st through the 4th Lateran Councils of the 12th Century were that period's equivalent of the G7 Powwows. And they concerned themselves tremendously with describing and codifying the shape of the new incest decrees, and with establishing methods of education and enforcement throughout Europe.

In recent times the Roman Church even engaged in a little bit of incest redefinition. This nicely illustrates pre- and post-Vatican II Canon Law incest taboos.

Pre-Vatican II


Post-Vatican II

Women whom Ego cannot marry are shaded in red
posted by meehawl at 2:47 PM on January 30, 2005

That's really interesting meehawl - thanks!

But I do think an important point may be being missed in the last bunch of posts.

Much has been made of the fact that incest taboos vary widely from culture to culture. Some have taken this as an argument that incest taboos are entirely cultural artifacts (imposed rather than instinctual.) But I'm not sure this is actually the argument being made, and I'm not sure it's true if it is.

What varies from culture to culture seems to be the extent of what is defined as incest. An incest taboo per se, comprising at least sibling pairs and adult/child pairs, seems pretty near universal, with the only exceptions I know about being clearly pretty deliberate ones imposed after the fact for certain situations or groups - although there are actually quite a number of such (incidentally, how come everyone brings up the European royals as evidence of the potential negative effects of inbreeding, but no one brings up the Hawaiian royals as evidence of the potential positive ones?)

So, we might postulate - any definition of incest which goes beyond one degree is almost certainly an imposed cultural artifact - quite probably deliberately introduced as a piece of social engineering at some point.

However, the origins of the taboo against first degree incest are murkier. Its universality from culture to culture implies that it transcends cultural origins; however, the frequent violations of the taboo, requiring cultural (legal) reinforcement, imply that, if instinctual, it's a weak instinct.

So one theory could be - there is a human instinct against first-degree incest, which is somewhat weak for evolutionary reasons (a limited amount of inbreeding may be beneficial, and particular circumstances may also make it essential to survival.) This instinct leads many but not all to feel revulsion at the idea, so it became enshrined in law and, frequently, artificially extended out for cultural or practical reasons, or, less frequently, artificially overridden for cultural or practical reaons.

Incidentally, the instinct (if such it is) seems to be activated by being raised in the same household; several studies have noted that siblings raised apart often find each other highly attractive (including a study with one of my favorite names ever, "Sex and the Perfumed Rat".) This is possibly anecdotally born out a bit by the responses on this thread - people seem to find the idea of people raised together having sex much more repellent than the idea of siblings who meet as adult strangers having sex. So if it is an instinct, it's activated as part of development, and it can be reinforced or overridden by cultural cues (children from families with low sexual boundaries are more likely to experiement with incest, for example.)

Sound reasonable?
posted by kyrademon at 4:37 PM on January 30, 2005

kyrademon, congratulations on managing to squick nearly all of Metafilter with one post. A prodigious achievement, indeed!
posted by NortonDC at 12:03 AM on January 31, 2005

children from families with low sexual boundaries are more likely to experiement with incest

I'd require clarification and evidence for this sweeping statement.

Clarification: how do you define "low sexual boundaries".

Evidence: rate of incest (monitored or self-reported) within such previously defined family units as compared with groups not within such definition.
posted by meehawl at 11:15 AM on January 31, 2005

kyrademon: Your last post made me think of this: In looking through Primate Paridigms to see how the monkeys deal with incest, I found that Feddigan pointed out that only mother-son and uterine siblings were known (most, although not all, monkeys avoid these couplings). I think that it would be fair to postulate that father-daughter (or son) and paternal sibling incest are very likely culturally constructed because they require knowledge about paternity.

meehawl: very cool stuff. Where did you get the kinship diagrams? I've been thinking over the course of this thread of the way in which prefered marriage partners (which are kind of the mirror image to incest partners) are heavily influenced by factors like property rights. I'm thinking in matrilineal societies, though, and it gets a little mind boggling to talk about without some diagrams.
posted by carmen at 3:16 PM on January 31, 2005

where did you get the kinship diagrams

Check the HTML, although I referenced the site directly.

Pne of the greatest modern analysts of the evolution of family structures in Western societies is Georges Duby - tracing the tension between the socially constructed ideas of kinship and the genetic imperatives of sexual reproduction are a speciality of his, primarily the medieval period. I like that era because it's like the phase change between the ancient and the modern. Many of the ancient European ideas about kin and incest make absolutely no sense to us today - they are more foreign and removed from our comprehension that pretty much any marriage/kin relationships that exist throughout the vast majority of the world today. But during the medieval period much of what we today take as granted, fixed, and absolute began to crystallise, some of it as emergent, de novo, and some of it as consciously created and regulated.

There's a great book I return to again and again, From Ancient Goddesses to Christian Saints, that has some absolutely astonishingly detailed chapters conerning all the various ancient Greek marriage/kin structures and how they competed with each other economically. So much of history is written as the dry tales of battles and kings, but when you get down to the nitty gritty a lot of the success or failure of specific Greek city states seems to have had a lot to do with how sheep (ie, wealth) were differentially redistributed within kin arrangements. Was incest/consanguinity banning calculated through patrilineal or matrilineal descent? How were aunts and uncles defined? What was the relative importance of the natal versus the conjugal kin? Did incest regulation skew remain constant, or oscillate between matrilineal or patrilineal? What was the velocity of the dowry property (horizontal, diagonal, direct descent, etc). How strict were the incest taboos (legal, social, kin enforced?). Could families *pay* or perform tasks or euergetism to overcome incest obstacles for profitable matches? And so on.
posted by meehawl at 6:02 PM on January 31, 2005

where did you get the kinship diagrams

Check the HTML, although I referenced the site directly.


Eek! Sorry, I was in a hurry, and I somehow got it in my head that you had found a way to make them yourself....

Your references look great. I'm going to try to pick up a copy of "A History of Women in the West" tomorrow. I'm working on cultural constructions of kin and gender for my master's and Duby looks like he'll be pretty relevant. Thanks!
posted by carmen at 8:04 PM on January 31, 2005

meehawl, I was basically thinking of the idea that children frequently imitate the sexual behavior they are exposed to, and therefore experimentation between siblings is more common in households where children visibly witness a lot of sex. I know that's a fairly widely-held psychological theory, although I admit I'm a bit too tired to look up links right now. I'm not sure how reliable the evidence is. I do know that sibling-sibling sexual abuse is more common in households with parent-child sexual abuse, and that there's plenty of research on that, but that's not quite the same thing.

(Incidentally, does anyone know if completely nonrelated children - both culturally and genetically; I'm not talking about adopted kids - who are raised in the same household have any kind of tendency to regard each other as sexually off-limits? If they don't, wouldn't that be a powerful argument that incest-avoidance is pretty much completely learned behavior? Is my logic followable there? I'm postulating:

1) Human incest-avoidance only seems universally and cross-culturally applied in "same household" cases;
2) If there is an actual incest-avoidance instinct, it is therefore activated by some kind of trigger in post-birth development;
3) It should therefore be triggerable by anyone you're raised with, since presumably genetics cannot be "sensed" that finely or incest-avoidance behavior wouldn't need a "same household" trigger in the first place;
4) We would expect adoptive siblings to be considered off-limits sexually in this case, and that seems to be born out;
5) But we would also consider children of entirely different families raised together in a single household to consider each other "off-limits" if so;
6) So, if children of different families (culturally permissible) raised together have no revulsion towards the idea of sexual experimentation with each other, but non-genetically related (adoptive) children of the same family (culturally impermissible) do, incest-avoidance might be best viewed as almost entirely a learned behavior. If they both tend to feel some degree of revulsion, even if there's a cultural permission, incest-avoidance might best be viewed as a instinctual tendency.

Anyone know about any research along those lines?)
posted by kyrademon at 10:56 PM on January 31, 2005

does anyone know if completely nonrelated children - both culturally and genetically; I'm not talking about adopted kids - who are raised in the same household have any kind of tendency to regard each other as sexually off-limits?

There's a lot of work done relating to this. Look up studies of teenage and adolescent sexuality in kibbutzim. You get all the emotional entanglement of incest, without any of the genetic input.
posted by meehawl at 3:59 PM on February 1, 2005

"You get all the emotional entanglement of incest, without any of the genetic input."

You mean there's incest taboos without genetic relatedness. That doesn't mean, at all, that the incest taboo isn't genetic.

And kyrademon, I don't see how for these purposes children raised in the same household aren't necessarily culturally related.
posted by Ethereal Bligh at 10:24 PM on February 1, 2005

EB, that's not the point I was trying to make. In fact, it's kind of the opposite.

I was positing that if children raised in the same household who are clearly neither genetically nor culturally related (I'll explain more what I mean by that in a sec) do *not* experience revulsion at the idea of sex with each other, then it's a reasonable theory that incest taboos are almost entirely learned behavior - if you feel it towards people culturally marked "no" but don't feel it towards people culturally marked "OK" who should be setting off the exact same developmental trigger if there is one, then it would seem to be learned behavior. See my last post for the reasoning (and bear in mind, we’re already operating under the assumption that if incest-avoidance is and instinct, it’s triggered in post-birth development, for reasons explained in earlier posts.)

Meehawl indicates there are studies of children raised in communal situations who do feel the "emotional entanglements" of incest with each other. I'm not sure exactly what that means, and I'm having difficulty finding the studies referred to, so I hope meehawl posts a link. "Emotional entanglements" does not necessarily mean "feel revulsion at the idea of sex with", so we may be talking about two different things.

Now, to clarify my earlier point - children raised in the same household may, in fact, be culturally related, and frequently are. But there are settings (kibbutzim are a great example, some American communitarian societies are another) where children are essentially raised together and no one would find it amiss if they ended up dating, having sex, or marrying, because they are not considered, culturally, to be related at all - simply raised communally. I think it would actually demonstrate a lot to see if, unencouraged, incest taboos crop up between such people anyway. If they do, that's evidence that there may be some instinct set off in development. If they don't, that's evidence that it's pretty much learned behavior.
posted by kyrademon at 11:58 PM on February 1, 2005

Ah. Thanks for the clarification.
posted by Ethereal Bligh at 12:10 AM on February 2, 2005

Look up Shepher's studies of apparently inculturated exogamous instincts within kibbutz-reared non-genetically related individuals.

I suspect some exposure during early childhood may cause some genes or cluster of genes to express that tend to downregulate any response to immune system profile scents emitted by individuals imprinted as "family". Or simply failt to produce an appropriate response. Then you get into a consideration of whether desire is a push or a pull phenomenon.

By emotional entanglement, I meant that such physiological sensations are not absolute governers of behaviour, but are one component in the complex actions of teens and adults. Some people will be repelled by the sensations, others will not.

It's also possible that the imprinting may not happen during the later life cycle of the individual but is in fact the result of some unknown consequence of maternal imprinting on the developing zygote. Much as the body plan is laid out by maternal homeobox proteins that interact directly with the zygote's DNA, it's possible (though much less likely) that imprinting is neonatal. I am impressed at some studies that seem to link a stressed maternal natal environment to a predispositon to risky behaviour in later life by individuals. It seems that some sustained downregulation in the response to epinephrine. If the maternal environment can influence some specific behaviours in individuals 20/30/50 years later, then why not others?
posted by meehawl at 4:49 PM on February 3, 2005

Thanks! Very interesting. Lends itself more to the "instinct set off in development" model". Personally, I'd be more partial to the idea of it being set off later than neonatally, given that it seems very influenced by with whom you are raised.
posted by kyrademon at 10:13 AM on February 4, 2005