I'm going to continue my discussion of moral purity, this time speculating on sex, sacredness and disgust. I'll begin with a conversation that took place over the weekend, in the car.
She: I'm thirsty.
Me: You can have some of my drink.
She: As long as you're not near the bottom of the can. I don't want your backwash.
Me: A little late to be worrying about that, don't you think?
A curious facet of sex is that the more exciting aspects require contact with things that we can find disgusting outside the throes of sexual passion. It seems that during sexual excitement, the reproduction imperative temporarily suppresses the disgust reaction. The latter was probably selected in our evolution by reducing exposure to communicable diseases, but the urge for sex was also selected, so we have powerful urges to do things that can also be viscerally aversive.
If we accept that this biological tension exists, then it doesn't require a great leap of imagination to see this tension as a progenitor of abstract moral tension about sexuality. Consider that sex is often thought of as dirty, sinful and degrading, but the very same act becomes sacred if a marriage rite has been performed beforehand. The "dirty" act becomes clean through ritual, which, by the way, is not dissimilar to the obsessive-compulsive adoption of rituals to ward off contamination fears.
I'm certainly not the first person to note all of this. I'm merely offering this quick presentation as groundwork for a future post on the moral condemnation of homosexuality and liberal versus conservative views of same-sex marriage.
For some helpful reading outside this blog, I highly recommend Jonathan Haidt's work. If you're unfamiliar with Haidt, I would urge you to read Haidt and Joseph, 2004. He has since expanded on that work considerably, but that paper lays out the foundation of his thinking about morality. The article is a relatively quick read, chock full of little gems of insight into the psychology of morality.