Julie and Mark are sister and brother. They are traveling together in France on summer vacation from college. One night they are staying alone in a cabin near the beach. They decide that it would be interesting and fun if they tried making love.
At this point my sister starts making a disgusted face.
At the very least, it would be a new experience for each of them. Julie is already taking birth control pills, but Mark uses a condom, too, just to be safe. They both enjoy making love, but decide not to do it again. They keep that night as a special secret, which makes them feel even closer to each other.
And at this point my sister explodes, “Ugh! I’m EATING!”
And I was like, “Really? You react that strongly to this story?”
I knew what was coming from the first sentence, so I don’t know for sure how I would have felt without that prior knowledge, but I had literally no response to this story.
Now if you asked me how I would feel about having sex with my sister or brother, I would absolutely give you the same reaction my sister had to this story. Absolutely. BLEURGH!! HELL NO!!! No offense to my siblings, but BLEURGH!!!
But the story of Julie and Mark isn’t about me, it’s about two strangers, whose sexual bodies are their own to do with as they will; the night described was fully consensual and offered no chance of pregnancy, which is the real risk associated with sex between full siblings – and is probably the source of the most nearly universal sexual taboo: incest.
(I would add that when Haidt was describing Buddhist monks “meditating on decaying corpses” to change their mental associations with desirable things, I too was eating and I couldn’t chew, so grossed out was I by the idea of rotting corpses. Gross. So it’s not like I’m undisgustable.)
This gross-out response to what OTHER people do with their bodies is generally related to the “purity” moral foundation – moral disgust is the description of the emotional state it generates, and it’s a BIG PROBLEM for political issues related to sexuality and reproduction, because here’s an important thing:
Disgust related to non-normative sex (sex with siblings, sex with animals, sex with inanimate objects, etc) DOES NOT VARY based on political affiliation. Progressive and conservatives alike are equally likely to say that a description of a sexual scenario that grosses them out is “Just Wrong” because it grosses them out. The one exception is same-sex sexual encounters. People who identify as politically conservative react to scenarios of gay sex with disgust, while politically progressive people react to those scenarios neutrally.
It’s a phenomenon I’ve mentioned a couple of times, but it’s worth spelling out. Indeed, it’ll be a crucial target of intervention in order for attitudes toward sex to change, to open up space for diversity and acceptance of harm reduction practices associated with higher risk behaviors.
Sex positivity is a public health intervention. It’s as important for liberals (like my lefty loony sister) as conservatives. And yes, the world will be a better place when everyone can hear stories about non-normative but low-risk sex without a sense of disgust. Definitely.