AN I.O.U.: Eugene Volokh asks opponents of same-sex marriage to describe the “mechanism” by which same-sex marriage will weaken reg’lar old marriage. I’m working on a piece on this very topic, which I hope to be able to post shortly. Here are the five premises which I hope will help illustrate one of the mechanisms (though only one) by which same-sex marriage will affect marriage-in-general.

I. People make lots and lots of their decisions based on self-image and role modeling.

II. Marriage is still glamorous and still thought to include, as an aspiration, lifelong sexual fidelity.

III. Same-sex couples have much less reason to insist on sexual fidelity than opposite-sex couples do.

IV. “Straight” people are not especially heroic.

V. People are more likely to do difficult and even heroic things when those choices receive praise from society.

More to come; this is my reminder that I promised to post an explicit description of how this particular mechanism operates.