Same-sex marriage advocates are convinced, and want to convince the rest of us, that SSM is a genuine form of marriage, that a given same-sex couple’s closer and binding relationship is or at least can be an instantiation of real marriage, and that this is why it is right for the law to treat it as marriage.
The idea, obviously, is that SSM is really marriage.
Now, this could be true, but obviously it’s controversial. It seems that one thing that could help settle the controversy would be to ask what makes it true, if it is true. What conditions could make it the case that SSM is really marriage?
It seems to me that one of those conditions must be something like this: What is essentially and inherently true about marriage is true about certain same-sex relationships just as it is true of certain opposite-sex marriages.
That is, there must be some set of essential truths about marriage that are as true of certain same-sex relationships as they are of certain opposite-sex relationships. Only if same-sex relationships can fulfill that set of essential truths do we have a moral responsibility to recognize them as such in law. If there is something essentially true of marriage, which same-sex relationships never can fulfill, then there is no moral obligation or responsibility for the law to recognize same-sex relationships as marriage.
My question for same-sex marriage proponents, then, is this: What is it that is essentially true about marriage, that makes it true that same-sex relationships can properly be called marriage, and should be recognized as such by the law?
I’ve been asking this in comments, and the tendency there has been to answer, “The law recognizes them as marriage, therefore they are marriages.” This answers a different question, however. Undoubtedly the law can re-define marriage so that same-sex unions are included in the definition. That’s not controversial. The controversy is over whether the law should do that. That it can do that is no reason, by itself, to conclude that it should do that.
And it seems to me that the only way in which it becomes a moral responsibility for the law to recognize same-sex unions as marriage is if same-sex unions are (or can be) instances of marriage. The law has a moral responsibility recognize X as a member of the class Y only if X actually is a member of Y. Otherwise, while it may be possible for the law to declare X a member of Y, there is no obligation for the obligation for the law to treat X as a member of Y.
How then do we know if X is a member of Y? We know it by understanding Y what why is, and whether X meets the definitional characteristics that make Y what Y is.
This is precisely what I am wondering about the SSM debate: can SSM advocates produce a definition of marriage that explains why same-sex unions can be and ought to be regarded as instances of marriage.
In order for this definition to have moral force, it needs to be an essential definition, that is, it must get to the essence of what marriage is, or, it must explain what marriage essentially is. If SSM only speaks of contingent truths or opinions regarding the meaning of marriage, then SSM opponents can legitimately and rationally wave those things aside as mere opinion, or contingent truths, with no moral force behind them.
So again I ask, what is it that’s essentially true about marriage that makes it true that same-sex unions can be included as instances of marriage, and that the law ought to recognize them as such?
A final, very crucial word: the second part of this question has to do with same-sex unions. It’s not the first part of the question. The first part has to do with what marriage essentially is. I urge readers not to skip the first part, since it’s the part that’s most important in this context.