And not because of moral reasons, it's simply a matter of practicality. I've never seen a polygamous relationship in which every participant was happy and content. Because of my research into alternative lifestyles, I actually know a lot of people who are in polygamous relationships (there are support groups for that, you know). I don't think it is immoral, as long as all parties involved are consenting adults.
However in practice, such a relationship requires way too much energy to maintain, and one or two people are always left feeling unhappy, undervalued, not needed, and not loved. Human beings are selfish and possessive, especially when they're in love. Very few people are capable of sharing their loved ones with other people, even under the pretense that you receive love from the other person. This is especially true if the polygamous relationship is 1 male + multiple females or 1 female + multiple males. One will undoubtedly become the favorite, and the other will end up resentful and feeling depressed.
An ideal situation, which most polygamous relationships I knew were trying to achieve, is somewhat a "network" of love, instead of a pyramid. For example, in a relationship with one male and three females, if the love exists only between the male and each female, it's not going to work. It has to be male and female, and female and female, in other words, everyone needs to love everyone. The male needs to love females A, B, and C equally, and females A, B, and C needs to love each other and the male equally. This kind of relationship is impossible.
On legal end, polygamous relationships can be a legal nightmare whether one party wants to leave the relationship or all parties wants to dissolve the group. You think two people divorcing is hard? Try five.
So all in all, even if polygamy were legal, I wouldn't go for it, simply because the chance to have a happy relationship is probably smaller than winning a lottery. I don't even spend a dollar to buy a lottery ticket, why would I invest my energy and effort to something that's bound to fail?
Some people mentioned historical polygamy and open relationships, so I feel that I should clarify my attitude toward these topics:
Almost all historical polygamy I know is based on a structure of one male plus multiple females (polygyny). And most of these family models were extensions of a patriarchal society in which women were considered property instead of human beings in equal standing of men. The women's emotional and physical well-being was largely ignored. While such a model might work for many cultures over many thousand years, it is wrong in the same way slavery is wrong. Just because we've been doing it for however long, or due to the fact that some people are still doing it, doesn't make it right.
However, it is worth noting that polygyny is a quite popular male sexual fantasy. Many males enter this alternative lifestyle under the pretense that he would be able to "own" multiple female willing slaves, with little or no regards to their feelings and safety. That is not polygamy, that is abuse.
Open Relationship vs. Polygamy:
For many people, these two are exchangeable. But for me personally, and for many polygamists I used to know, they're very different. Polygamy means commitment. It is the same way you are committed to a monogamous relationship. For example, in a one-female, two-male relationship, all three of them need to be committed to each other (not just the female to each of the two males). It's a promise you would love and care for everyone involved in the relationship, and be loyal to all of them. If one person want to bring in a new person to the relationship, all people involved need to love this new person. (It's the same way with monogamy: If two of you want to get married, both of you need to agree to the commitment)
An open relationship, as is suggested, is a relationship of two people, and it's open. It often started with one traditional monogamous relationship, and opened up due to various reasons (getting bored with relationship, want to experiment, one person can't stay loyal, the other person decide "what the hell, I'm gonna have some fun myself" blah blah blah). While there might be commitment between the initial two people, there's no commitment existing between new people involved. Say a couple has an open relationship, female and male are free to date outside their relationship with or without the approval of their initial partner. In most cases, their external relationships are more or less a fling (passionate and intense they might be). I imagine a lot of "successful polygamous relationships" are more or less "successful open relationships." Since such relationships don't require commitment of all parties involved, it's a lot easier to manage.
In the end, however, the name is largely irrelevant. As long as all parties involved are consenting adults, do whatever you want behind closed doors.
An very unrelated side note, I just thought about this in relation to this question.
So there is actually one female-centric polygamous society that I know, the . Mosuo society is matriarchal. The family structure surrounds a female matriarch (often the grandmother). Women do not get "married off" to another family; they live with their female relatives. When young women reach the right age, her family sets up a separate house, and young men would come visit during the night and leave the next morning. Children born to the woman do not know who their father is. And they are raised by the their mothers and other family members on her mother's side.
Males also live with their female relatives, they go visit girls at night and return to their own home the next day. They'll help their sisters and female cousins to raise their children (his nephews), but not his own children.
There are reports that one female will only receive one male for a prolonged period of time, but they don't live together, and there's no official/recognized commitment.
This is quite an interesting social/family structure, and surprisingly stable. Mosuo people lived like this for thousands of years. I think this is probably like a huge network of open relationships.
Answer by Eric Pepke:
I'm already poly, though situationally pretty mono. I have been trying to get another lover down to live here, but we have to move first, not because of her, but because of the dog.
I am not, however, so keen on the gamy part in general. Of course, it's a fantasy to think that it would ever happen in the Americas (OK, except for Paraguay after the war of the triple alliance). Still, I would have to look at the laws to see whether it would be desirable or not. If it were possible to get a scaled family health plan without having to incorporate, that might tip the scales.
Speaking of which, we manage to handle corporations and partnerships with more than two people. Maybe that's impossible and too complex, too. Maybe all that should stop.
So there's the poly question and the gamy question. The poly part already works in my life, far better than when I tried to be mono. That was terrible.
I feel a disconnect when I hear people, even if they aren't being moralistic, talking about how difficult or unrealistic or against human nature poly is. I have no idea what these people are talking about. First, there seems to be the assumption that everybody is alike, and second, that the thing it must necessarily be compared to, monogamy, is just a field of happy bunny rabbits all the time.
The former is just dumb. My mono relationships have been terrible, though I was totally monogamous in them. The poly ones haven't been trouble-free, but they have been way, way better. There are some people who are naturally monogamous, but fewer than those who claim to be.
I can't blame them for the second observation, except maybe for being ignorant of confirmation bias. Anybody looking at poly from the outside is going to see a tiny minority of vocal activists and advocates. (That or the FLDS.) They have all this primary and secondary stuff, and they love acronyms like NRE and OPP, and they rant about Unicorn Hunters and seem to love literary criticism. They are constantly trying to define what poly is or should be for everybody. I can't blame anybody for believing them, though they are, of course, full of s**t, and I take every opportunity to remind them. But they're loud.
In my experience, that sort of person invariably has adrenal glands that work a lot better than their brains do. It is not surprising that their lives are more dramatic than usual.
The overwhelming majority of people, of any stripe, who just live their lives are invisible. (Opposite hybrids like me are incredibly rare.)
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