Is Disgust Real? (Part 2 of a series)

(See also: Part 1, Yes, Women Think Male Sexuality is Disgusting; Part 3, Disney Explains Disgust; and Part 4, Disgust vs. Aggression vs. Fertility.)

One of the theories that undergirds a large subset of my thoughts on how brains work is the idea that Disgust is a Real Thing.

I don’t just mean a mild aversion to things that smell bad, like overturned port-a-potties or that fuzzy thing you found growing in the back of the fridge that might have been lasagna, once upon a time. Even I have such aversions.

I mean reactions like screaming and looking like you are about to vomit upon finding a chicken heart in your soup; gagging at the sight of trans people or female body hair; writhing and waving your hands while removing a slug from your porch; or the claim that talking about rats at the dinner table puts you off your meal. Or more generally, people claiming, “That’s disgusting!” or “What a creep!” about things or people that obviously aren’t even stinky.

There is a parable about a deaf person watching people dance to music he can’t hear and assuming that the people have all gone mad.

For most of my life, I assumed these reactions were just some sort of complicated schtick people put on, for totally obtuse reasons. It was only about a year ago that I realized, in a flash of insight, that this disgust is a real thing that people actually feel.

I recently expressed this idea to a friend, and they stared at me in shock. (That, or they were joking.) We both agreed that chicken hearts are a perfectly normal thing to put in soup, so at least I’m not the only one confused by this.

This breakthrough happened as a result of reading a slew of neuro-political articles that I can’t find now, and it looks like the site itself might be gone, which makes me really sad. I’ve linked to at least one of them before, which means that now my old links are dead, too. Damn. Luckily, it looks like Wired has an article covering the same or similar research: Primal Propensity for Disgust Shapes Political Positions.

“The latest such finding comes from a study of people who looked at gross images, such as a man eating earthworms. Viewers who self-identified as conservative, especially those opposing gay marriage, reacted with particularly deep disgust. … Disgust is especially interesting to researchers because it’s such a fundamental sensation, an emotional building block so primal that feelings of moral repugnance originate in neurobiological processes shared with a repugnance for rotten food.”

So when people say that some moral or political thing is, “disgusting,” I don’t think they’re being metaphorical; I think they actually, literally mean that the idea of it makes them want to vomit.

Which begs the question: Why?

Simply put, I suspect that some of us have more of our brain space devoted to processing disgust than others. I can handle lab rats–or pieces of dead lab rats–without any internal reaction, I don’t care if there are trans people in my bathroom, and I suspect my sense of smell isn’t very good. My opinions on moral issues are routed primarily through what I hope are the rational, logic-making parts of my brain.

By contrast, people with stronger disgust reactions probably have more of their brain space devoted to disgust, and so are routing more of their sensory experiences through that region, and so feel strong, physical disgust in reaction to a variety of things, like people with different cultural norms than themselves. Their moral reasoning comes from a more instinctual place.

It is tempting to claim that processing things logically is superior to routing them through the disgust regions, but sometimes things are disgusting for good, evolutionarily sound reasons. Having an instinctual aversion to rats is not such a bad thing, given that they have historically been disease vectors. Most of our instincts exist to protect and help us, after all.

(See also: Part 1, Yes, Women Think Male Sexuality is Disgusting; Part 3, Disney Explains Disgust; and Part 4, Disgust vs. Aggression vs. Fertility.)

16 thoughts on “Is Disgust Real? (Part 2 of a series)

  1. I really love the balance between serious and well thought through topics and really funny writing in your blogs. This really made me giggle!

    With some disgust-prone people I tend to think their parents just told them things were icky a bit too often. I do get what you mean though. My mom literally starts gagging just thinking of the dead headless mouse the cat brought in a week ago. Hysterically funny as this may be to witness, it’s no game for her. Her body is totally prepared to go into full evacuation mode over something that isn’t even present in the room. Fascinating!


    • Thank you! I am glad to have entertained.

      Oh, the dead mice I have cleaned out of cages and traps… and swept off the porch, lovely gifts from the cats. When one must handle dead mice, it is rather useful not to start gagging. But in the long run, it may be evolutionarily sounder to find mice disgusting. :)


  2. Heh. Examine your feelings on first degree incest (not abstract examples, but placing yourself in that situation), for example. Not feeling disgusted about that is a rare exception.


    • I didn’t grow up around my siblings, so I don’t have any real instinctual aversion to them. (No attraction, either.) But kids who grow up around adopted or step siblings from birth, I hear, end up with strong aversions to romantic entanglements with each other. This is just because the brain does the best it can with the kinds of information it normally has.

      As for my parents, to be honest, I don’t even like to touch them. That is not disgust in the sense of what I think of feces, but I just… I hate it, I absolutely hate it, like stubbing a toe.


  3. It is tempting to claim that processing things logically is superior to routing them through the disgust regions, but sometimes things are disgusting for good, evolutionarily sound reasons.

    Agreed. I’d go farther: Anything that is widely considered disgusting is so for good evolutionary reasons.

    Jonathan Haidt’s The Righteous Mind is pretty good on the subject of moral foundations the five (or six if you believe “liberty/oppression” is a real axis) axes of moral judgement. He’s very good at pointing out how educated Westerners tend to be one way, favoring harm/care + fairness (deontological) sort of thinking, and the rest of the world tends to be more balanced. Of course he never quite manages to extract himself from the Western way of moral thinking when thinking about moral foundations.


    • Key word “widely”, of course.
      Emotions generally exist for some sort of sound evolutionary reason, even if they manifest themselves in random ways that occasionally need to be ignored, eg, the tendency to treat as human anything with a human face, even if it’s just a potato. Much of advertising exists to hack our emotional responses in this way.

      Thanks for the recommendation.


  4. Most of our instincts evolved to protect and help us. Agreed, but for what time period? Many of our evolutionary instincts are maladaptive for a modern context or are simply overworking. Take snakes for example. Most people are either fearful or disgusted towards them, and many crazy superstitions have grown around them through the ages for that reason, and although they might be a significant danger for certain times and places in the past, today they are much less of a danger, particularly in developed countries. And of course not all snakes are dangerous. Evolution though gave us an instinct to fear all of them, because it is less costly to avoid all of them rather than make a mistake and treat a dangerous one for a harmless one. But in the modern context we have many more dangers to look out for, e.g. naked eletrical wires, cars etc, for which evolution has not equiped us. On the other hand, this evolutionary baggage might prove harmful to biodiversity if people start killing every snake they encounter. So not all retained instincts are always unerring protectors. And given that we are not planning to return to a hunter-gatherer or small agriculturalist existence for any time soon, we don’t need any irrational overreaction anymore.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s