On Slippery Slopes and Polyamory

In my last post I argued that same-sex marriage is not a new phenomenon but, rather, the act of applying an old institution to couples who have historically been denied access to it. In an interesting comment on that post, blannphinella asked whether the marital kind of relationship can also be had by groups of more than two.

Put another way, does conferring a marriage on parties of three or more people involving simply making marriage as ordinarily conceived available to more seekers than have historically had access to it? Or does "marrying" a group of more than two necessarily involve changing the kind of relationship at issue? Can a triad possess a "marital" relationship that is the same in kind as what a pair possesses?

Now this question is important, because a common challenge to marriage equality is that it is a slippery slope to polygamy/polyandry. If we make marriage available to same-sex couples, then what's to stop us from making it available to groups?



Let me begin by saying a word about slippery slopes. Much slippery-slope thinking is fallacious, but it's not always fallacious. A slippery slope--from, say, allowing same-sex marriage to allowing polyamorous ones--might really exist, but only if the following conditions holds: Your reasons for allowing the former are also reasons for allowing the latter--and the latter doesn't have counterbalancing reasons against it that don't also apply to the former.

So, if your reason for favoring same-sex marriage is that you think anything goes in love--well, that's also a reason for favoring polygamy. So--relative to that reason--there is a slippery slope from same-sex marriage to polygamous marriage. But suppose your reason is this: Same-sex couples are just as capable of having a relationship of the "marital kind" as heterosexual couples, and there is no compelling state interest that can justify denying legal recognition to same sex couples who do pursue a relationship of that kind.

For a slippery slope to exist relative to that reason, you'd need two conditions to hold, one positive (something must BE the case), the other other negative (something that must NOT be the case). The positive condition is this: it must be the case that groups of more than two can have a relationship of the "marital kind."  The negative condition is this: it must not be the case that there exists a compelling state interest that justifies withholding marriage from groups (even if not from same-sex couples).

The question of whether a triad (or larger group) can possess a marital relationship bears on the first of these conditions--the positive one. Can the marital relationship be extended to triads and larger groups without fundamentally altering its character?

In answering this question, it's important to make a crucial distinction. Suppose we have a triad of people: Abe, Bill, and Cathy. There's a big difference between holding (a) that Abe, Bill, and Cathy can have a marital relationship as a group, and (b) that Abe can have a marital relationship with Bill, Bill with Cathy, and Cathy with Abe, all at the same time. Now it seems clear that if a marital relationship is characterized by sexual fidelity, then (b) is not possible. If Abe has a marital relationship with Bill, and if a marital relationship is characterized by sexual fidelity, then Abe cannot have at the same time a marital relationship with Cathy--since that would imply that he is not practicing sexual fidelity in relation to Bill.

So, if what you're talking about is (b), then the answer to our question would be no. You cannot have group marriages without changing the nature of the relationship. But what about (a)? Why can't we treat the triad as a unit the way that we do a pair, instead of treating the triad as three overlapping pairs?

There are cases in which you can do something along these lines. Suppose that, at a party, people gather to play Trivial Pursuit in teams. And let's suppose that, the number of players being what it is, there end up being two teams of three and one team of two. The only defining feature of a team is that teams are supposed to reach a consensus concerning what answer to offer. We can imagine that this mode of relating is formally the same for the teams made up of three players and the teams made up of two. The triads and the pair have the same kind of relationship--they can both be "teams" in the indicated sense.

But is this possible in the case of marriage, or does the addition of a third party essentially alter the nature of the relationship so that it no longer is a relationship of the same kind after all? Since sexual fidelity is part of our common concept of marriage, part of the answer to this question has to focus on sex.

Now with a triad, what does sexual fidelity look like? On the one hand, one could set up a rule requiring that sex always involve all three parties at once; on the other hand, one could allow any two in the triad to have sex without the participation of the third, and hold that fidelity is preserved so long as no one goes outside the triad.

If we go with the latter, it is quite clear that the relational structure of a faithful triad is quite different from the relational structure of a faithful pair. A faithful triad could be characterized by one party being left out, feeling jealous, playing someone's jealousies against the other, etc. None of this is possible with a faithful pair. So, going with the latter entails that "sexual fidelity" has a very different character than it has for a pair. It doesn't mean the same thing. And if "sexual fidelity" doesn't mean the same thing for a triad as it does for a pair, then "marriage" cannot mean the same thing (assuming marriage is characterized by sexual fidelity).

So, does "sexual fidelity" mean the same thing for a triad as it does for a pair if the triad observes a rule that all three parties to the triad have to be actively having sex with one another every time that sex occurs? The physical mechanics of sex being what they are, this arrangement might still be characterized by turn-taking, by someone feeling left out, by one party focusing more on one of the other members of the triad than on the third, etc. In other words, it's not clear that such a rule avoids the complex dynamics that are possible when pairing off is allowed. And so it's not clear that we have, even with this rule, a sense of "sexual fidelity" that is anything like what we'd have in the case of a pair.

But the mere fact that such a rule could be adopted at all (or not) seems to entail that a triad is different in kind from a pair when it comes to sex. For a pair, the commitment to only having sex with another member of the pair settles the matter of who has sex with whom. For a triad, the commitment to only having sex with another member of the triad does not settle this matter at all.

So, just in relation to the sexual dimension of marriage, it is clear that a triad cannot possibly have the same kind of relationship that a pair can have. And so it follows that we cannot extend marriage to groups larger than two without changing our understanding of what kind of relationship marriage is. On this dimension alone, there is no slippery slope from same-sex marriage to polyamorous marriage. And everything that we can say about sex can likewise be adapted to issues of romantic bonding that isn't explicitly sexual, and to other elements of marital relatedness. Adding a third party changes the very nature of the marital relationship.