One of his examples involves consensual incest between adult siblings who use contraception, whose behavior will never be repeated, and about whose sexual relationship no one will learn. I think this is a very effective example, because it demonstrates that truly harmless behavior can nonetheless arouse moral disgust in most of us, along with the inclination to pass negative judgments. The law reflects this inclination (in the case of incest) in that almost every state in this country prohibits incest, even when it involves consenting adults (though the content of the category is defined with varying breadth in different places).Emphasis mine.
After reading more about couples that were otherwise quite ordinary and simply sought the right to marry like other people could, I concluded that even though I and a majority of people find the idea of sibling incest disgusting, and perhaps in part because we do, it is very important to protect people who want to engage in such behavior from the consequences of our disgust, so long as the behavior harms no one.Thank you! Thank you! Thank you!!!
She goes on to demolish Discredited Argument #18 and thoroughly explains why Discredited Argument #1 should not translate to law.
As Ms. Colb demonstrates, we can be personally disgusted by something and recognize there is no reason to have laws preventing others from enjoying that thing. As more and more people become allies, we accelerate towards full marriage equality and other relationship rights for all.