Essentialism: Why a Washed Sweater Still Feels Like Its Owner

In psychology, essentialism is a way of representing categories: members of a category are assumed to share something inward, unobservable and causal, which produces their visible features and stays constant when those features change. A tiger raised among sheep is still a tiger. Two other senses are not this one: in philosophy, essentialism is the metaphysical claim that things really do have essential properties, a question about the world rather than about how people think, and Greg McKeown's 2014 book Essentialism is about doing fewer things on purpose.

Susan Gelman's work set out the psychological version. In her 2003 book The Essential Child she assembled evidence that essentialist reasoning appears early, before any instruction in biology, and is not a mistake children grow out of. It is useful: an essence is a placeholder for a causal story not yet known. If this animal is a bird, it probably has hollow bones, whatever it looks like.

The same habit becomes a problem when applied to social categories, which are built by history and circumstance rather than by biology. Nick Haslam, Louis Rothschild and Donald Ernst had people rate 40 social categories on nine elements of essentialism in 2000, and found two independent dimensions: how far a category is treated as a natural kind, and how far it is treated as a coherent entity with an inner core. Essentialism was not one trait people either had or lacked, and was not uniformly tied to devaluing a group.

Their follow-up in 2002 tested Allport's claim that believing in group essences is part of a prejudiced personality, and got partial support: essence-related beliefs were strongly associated with anti-gay attitudes, only weakly with sexism and racism, and did not form a consistent style across categories. The link is real in places, correlational, and specific to the category and the belief.

The second strand is about objects rather than categories, and it is the one the demo uses. Rozin and Nemeroff's work on contagion follows the same habit through contact: brief contact with a person is treated as leaving something of that person in the thing, and ordinary cleaning is not thought to settle the matter. Their interviews found several accounts of what that something is, from spiritual residue to plain association and symbolic meaning, with most people using more than one.

Paul Rozin, Linda Millman and Carol Nemeroff published "Operation of the laws of sympathetic magic in disgust and other domains" in the Journal of Personality and Social Psychology in 1986. They tested whether two rules anthropologists had described in other cultures, contagion (once in contact, always in contact) and similarity (the image equals the object), operate in educated American adults.

The 50 participants were people from the University of Pennsylvania community, about half of them students. Part of the study used real objects in the room: a sterilized dead cockroach dropped into a glass of juice, fudge shaped like dog feces, two bottles of sugar that the experimenter had labeled sucrose and sodium cyanide. Part was a questionnaire scored from -100, the most unpleasant experience imaginable, to +100, the most pleasant. Three of those questions asked about wearing a cleaned shirt in a style the participant liked: one from a used clothing store, one from someone they disliked, and one from someone they liked.

The shirt that had belonged to a disliked person averaged 36.4 points below the shirt of unknown history, with 50 people answering and the great majority moving in that direction. The shirt from a liked person averaged 12.9 points above it, with 49 answering. Juice that had touched the sterilized roach dropped about 102 points on the 200-point scale, while juice touched by a candleholder dropped 3. Sugar from the bottle the experimenter had labeled sodium cyanide was passed over in favor of identical sugar from the bottle labeled sucrose by 41 of the 50 people, who could explain perfectly well that both bottles held the same sugar. When participants labeled the bottles themselves, in a second round with 38 of them, the preference was smaller and still there.

Carol Nemeroff and Rozin extended the interpersonal half of this in 1994, comparing how American adults reason about catching germs with how they reason about picking up someone's qualities through their possessions. The two followed similar rules, with one asymmetry: influence from a person was treated as more persistent, resistant to the cleaning that would settle a question about germs.

Essence thinking shows up in markets, in moral judgment and in how groups are described. The rows below are illustrations, not findings from the studies cited here.

Essence thinking is not an error to be deleted: it is how categories are stored, and it earns its keep with animals, plants and materials. The work is noticing where it has been applied to something with no essence to find.

• Ask what the essence is supposed to be. If no one can name the inner property, or the only evidence for it is the pattern it was invented to explain, it is a placeholder rather than a cause.
• Look at the variation inside the category. Essentialist descriptions survive by treating the average as the nature; the spread within almost any human group is wider than the gap between groups.
• Separate the object from its history on paper, in two columns, then decide what each is worth to you.
• For social categories, name the mechanism. Laws, money, schooling and migration explain group differences in ways that an inherited nature cannot, and they can be checked.
• Watch the language of fixed causes: it is in their nature, a born salesman, a gene for shyness. Each forecasts the same conclusion, that nothing can change.
• Expect the pull to stay. Rozin's participants knew the shirt was clean and the sugar was sugar, and still chose the other bottle.

Essentialism is a belief about inner natures. Its neighbors are beliefs about groups, about individuals, and about what follows from them.

• It is not stereotyping, which is the content of a belief about what a group's members are like. Essentialism is the deeper assumption that the content comes from a shared inner nature, which is what makes a stereotype feel like biology rather than a guess.
• It is not prejudice, which is a negative attitude toward people because of their group. Haslam and colleagues found essence-related beliefs linked to prejudice for some categories and barely at all for others, so the two are related rather than the same.
• It is not out-group homogeneity bias, the perception that other groups are more alike than your own. That is a judgment about variability; essentialism is a claim about where the similarity comes from.