How Disgust Explains Everything

The most important disgust accounts following Darwin come from a pair of Hungarian men born two years apart, Aurel Kolnai (born in 1900) and Andras Angyal (1902). I haven’t found any evidence that they knew each other, but it seems improbable that Angyal, whose disgust paper came out in 1941, didn’t draw from his countryman’s paper, which appeared in 1929. Strangely enough, the Angyal paper contains no reference to Kolnai. One possibility is that Angyal failed to cite his sources. A second possibility is that he was truly unaware of the earlier paper, in which case you have to wonder whether there was something so abnormally disgusting about Central Europe of the early 20th century that two strangers born there were driven to lengthy investigations of a subject no one else took seriously.

A third possibility is that Angyal started reading Kolnai’s paper and gave up midway through in frustration. While brilliant, Kolnai’s writing has the density of osmium. His paper is rife with scare quotes and clauses layered in baklava-like profusion. Nonetheless, Kolnai was the first to arrive at a number of insights that are now commonly accepted in the field. He pointed to the paradox that disgusting things often hold a “curious enticement” — think of the Q-tip you inspect after withdrawing it from a waxy ear canal, or the existence of reality-TV shows about plastic surgery, or “Fear Factor.” He identified the senses of smell, taste, sight and touch as the primary sites of entry and pointed out that hearing isn’t a strong vector for disgust. “One would search in vain for any even approximately equivalent parallel in the aural sphere to something like a putrid smell, the feel of a flabby body or of a belly ripped open.”

For Kolnai, the exemplary disgust object was the decomposing corpse, which illustrated to him that disgust originated not in the fact of decay but the process of it. Think of the difference between a corpse and a skeleton. Although both present evidence that death has occurred, a corpse is disgusting where a skeleton is, at worst, highly spooky. (Hamlet wouldn’t pick up a jester’s rotting head and talk to it.) Kolnai argued that the difference had to do with the dynamic nature of a decomposing corpse: the fact that it changed color and form, produced a shifting array of odors and in other ways suggested the presence of life within death.

Angyal argued that disgust wasn’t strictly sensory. We might experience colors and sounds and tastes and odors as unpleasant, but they could never be disgusting on their own. As an illustration, he related a story about walking through a field and passing a shack from which a pungent smell, which he took for that of a decaying animal, pierced his nostrils. His first reaction was intense disgust. In the next moment, he discovered that he had made a mistake, and the smell was actually glue. “The feeling of disgust immediately disappeared, and the odor now seemed quite agreeable,” he wrote, “probably because of some rather pleasant associations with carpentry.” Of course, glue back then probably did come from dead animals, but the affront had been neutralized by nothing more than Angyal’s shifting mental associations.

Disgust, Angyal contended, wasn’t merely smelling a bad smell; it was a visceral fear of being soiled by the smell. The closer the contact, the stronger the reaction. Angyal’s study is even more delightful when viewed in the context of its preface, which explains that the material is based on observations and conversations “not collected in any formal manner,” and that the method, “if it may be called such,” lacked objectivity and control. Reading the paper 80 years later, as a replication crisis in the sciences continues to unfold, Angyal’s humility takes on a refreshing flavor. I’m just a guy noticing some stuff, he seems to say. Let’s see where this leads.

I first met Rozin at a Vietnamese restaurant on the Upper West Side in midsummer. He arrived in a bucket hat the color of Tang and a navy shirt with pinstripes. After ordering, we sat at a blond wood table and ate rice crepes piled with diverse vegetable elements. Rozin had ordered a green-papaya salad to share, and while spearing papaya he noted that “this, right now, is a form of social bonding — eating from the same bowl.” (He and a team did a study on it.) A fun thing about hanging out with a research psychologist is that he can usefully annotate all sorts of immediate lived phenomena, and in the case of Rozin, he may even have hypothesized the explanations himself. Our crepes, to take an example, were the width of basketballs — enough to feed six, easily — and yet we each polished off the jumbo portion. “Unit bias” is the heuristic that Rozin and his co-authors coined to describe the effect back in 2006. The idea is that humans tend to assume a provided unit of some entity is the proper and optimal amount to consume. This is why movie popcorn and king-size candy bars are treacherous, and possibly one reason French people — with their traditionally small portions — remain thin.

Rozin, who is now 85, was born in the Flatbush neighborhood of Brooklyn to Jewish parents who, though they hadn’t attended college themselves, were cultured and artistic and pleased to discover that their son was a brainiac. He tested into a public school for gifted children, left high school early and received a full scholarship to the University of Chicago, where he matriculated just after his 16th birthday. Upon graduating, he took a joint Ph.D. at Harvard in biology and psychology, completed a postdoc at the Harvard School of Public Health and in 1963 joined the faculty of the University of Pennsylvania, where his initial experiments centered on behavior in rats and goldfish. As he quickly worked his way up from assistant professor to associate professor to full professor, Rozin decided that he was tired of animal studies and wanted to focus on bigger game.