Same-sex marriage isn't a pre-existing institution. It's a recent one created in response to social and other needs that formerly went unrecognized. Legislators may not have fully realized that they were creating a new institution, but they were.
It's a new thing. It's not one that can fit into the old tradition. But the rights and privileges that go with same-sex marriage are arrived at by piggy-backing on those of traditional marriage.
The two institutions have this in common: They legally fall under the common name "marriage," and they both carry the same legal rights and responsibilities. And people engage in both of them for similar reasons. But that's about it for fundamental similarities.
Opponents of same-sex marriage see it as hijacking and corrupting the traditions underlying traditional marriage, and as a threat to what their own marriage "means."
But it isn't hijacking, and it isn't an attempt to infiltrate or invade the traditional institution. That can't be done.
Traditional marriage is heterosexual. Same-sex marriage recognizes its debt to traditional marriage. Traditional marriage is where marriage rights and obligations originated. It's the source of those attached in law to same-sex marriages.
If same-sex marriage is a new institution, why isn't it given a new name? Because the purpose of the new institution is to recognize certain rights and responsibilities for same-sex couples the same ones enjoyed by traditional married couples.
Rather than create a new set of parallel laws, it's better to reference them as those already attaching legally to the term "marriage," where settled issues of law can apply to both.
Traditional marriage isn't affected when a same-sex couple borrows ceremonies and practices from it to solemnize their union. Those traditions are secure; they aren't altered no matter who copies or borrows from them.
Proponents of same-sex marriage may be disturbed by the view that it's "not traditional marriage." Nevertheless it is a fact, and a harmless one. Same-sex marriage is a new thing. "Not the same as" doesn't mean "not as good as." Each is as good as the other.
Why do I think this is important? Because if all parties could realize that they are not fighting over a common turf to see who owns it, they would realize that there is nothing to fight over.
Traditional marriage and same-sex marriage aren't opposing institutions. They are parallel institutions, running alongside each other in a common direction on different tracks, not opposing each other like two locomotives trying to occupy the same track at the same time.
If all sides could realize this, each might become comfortable in its own skin, stop feeling threatened, and let the other side do the same. If they could.
Would it make those who oppose same-sex marriage because they despise homosexuality change their mind? No. But that's a group and an issue I'm not addressing.
Bangs L. Tapscott is emeritus professor of philosophy at the University of Utah and lives in Salt Lake City.