Here’s a question to sit with for a second. Someone offers you a shirt. It’s been washed five times and fully disinfected — there’s no dirt, no smell, nothing left on it in any way a lab could detect. But before all that washing, it belonged to someone you strongly dislike. Would you wear it?
Most people say no. Not “I’d rather not” — an actual, gut-level no, even after hearing the word “disinfected” twice. That reaction is worth pausing on, because it doesn’t make much sense on paper. The shirt is, physically, just a shirt. So what exactly are you saying no to?
There’s a name for this, and it’s older than clothing labels
Psychologists call it moral contagion, and it runs on something researchers describe as the law of contagion: once two things touch, some part of the mind treats them as permanently connected, even after every physical trace is gone. The idea comes from anthropological studies of what’s called sympathetic magic — belief systems where contact between two things is thought to create a lasting bond between them, “once in contact, always in contact.”
What’s strange is that this isn’t just a belief found in traditional or ancient cultures. Researchers Paul Rozin, Linda Millman, and Carol Nemeroff tested it directly in ordinary American adults and found it alive and well. In one part of their study, people were asked how willing they’d be to wear a cleaned shirt that had belonged to someone they disliked, compared to a shirt from someone they liked or a shirt of unknown history. The disliked person’s shirt was rated significantly less acceptable — despite being described as clean — a pattern the researchers linked to the same contagion response they found when people were asked to drink juice a sterilized cockroach had briefly touched (Rozin, Millman, & Nemeroff, 1986).
Your mind believes a bit of the person stays behind
Follow-up research by Carol Nemeroff and Paul Rozin dug into why this happens, and the explanation is worth sitting with: people seem to intuitively treat physical objects as carriers of a person’s essence — something like their inner nature or identity — that transfers through contact and doesn’t wash off with soap, no matter how thoroughly you explain the chemistry (Nemeroff & Rozin, 1994; Nemeroff & Rozin, 2000). You can show someone a lab result. You can explain exactly how detergent works. The feeling barely moves. It’s not that people don’t believe the science — it’s that the science is answering a different question than the one their gut is asking.
The same effect works in reverse, and it’s worth real money
Here’s where it gets more interesting: this isn’t only a disgust reaction. The same mental wiring runs in a positive direction too, and it’s a well-documented reason certain objects sell for extraordinary prices. Researchers Gil Newman, Gil Diesendruck, and Paul Bloom studied what they called celebrity contagion — the tendency to value an object more simply because someone admired once touched or owned it. Their research found that greater physical contact between a celebrity and an object increased how much people wanted it, for objects tied to people they liked (Newman, Diesendruck, & Bloom, 2011). It’s a large part of why a musician’s guitar, a designer’s sketch, or an athlete’s worn jersey can sell at auction for far more than an identical, untouched version of the same object. Nothing physical changed. The price is paying for the contact.
This doesn’t seem to be a modern quirk, either
One more piece worth knowing: this kind of contagion sensitivity hasn’t only been found in places with auction houses and dry cleaners. Researchers studying contagion beliefs across very different cultures, including small-scale societies with little exposure to Western consumer life, found the same underlying sensitivity to contact and contamination showing up in different forms (Apicella & Barrett, 2016). That’s a strong hint this isn’t a habit picked up from modern hygiene marketing — it looks more like a basic feature of how human minds process contact between people and objects.
So — illusion, or real?
Both, depending on which question you’re asking. Physically, it’s an illusion: a washed, sterilized shirt carries no trace of its previous owner that any instrument could find. But psychologically and behaviorally, the effect is real, replicated, and measurable — it changes what people are willing to wear, and it moves real money at real auctions. A feeling doesn’t need a physical mechanism behind it to shape actual decisions.
What this means for a brand-new, custom-made garment
There’s a quieter implication in all of this for anything made specifically for a brand, rather than resold or handed down. A garment produced new, to your own spec, for your own brand, has no previous owner and no contact history attached to it at all — it starts as close to a psychologically blank slate as a physical object can be. Whatever meaning it ends up carrying is entirely what your brand puts into it from the first wear, not something inherited or worth worrying about.
And the positive side of contagion isn’t just a curiosity for auction houses — it’s a large part of why creator and founder-led merchandise works as well as it does. A hoodie tied to a creator, a founder’s story, or a brand a customer truly admires isn’t just fabric and a print; on some level, it’s carrying a small piece of that connection, the same mechanism driving six-figure celebrity memorabilia sales, just at a very different scale. It’s one more reason the story behind a product, not only its stitching, is doing real work on the person wearing it.
Quick Questions
What is moral contagion in psychology? It’s the tendency to believe that a person’s qualities or “essence” transfer to objects they’ve touched or owned, and that this connection lingers even after the object is cleaned or the contact is long over. It was first demonstrated in controlled experiments by Rozin, Millman, and Nemeroff (1986).
Is it irrational to not want to wear a disinfected item that belonged to someone you dislike? By physical and scientific standards, yes — cleaning removes any real trace. But the discomfort is a well-documented psychological response, not a personal quirk, and studies show it appears consistently across people and cultures.
Does contagion thinking only work negatively, or can it add value too? Both. The same mental process that creates disgust toward a disliked person’s belongings also increases the perceived value of objects connected to someone admired — this is called celebrity contagion (Newman, Diesendruck, & Bloom, 2011).
Why do celebrity-owned items sell for so much more than similar items? Research shows that greater physical contact between a celebrity and an object increases how much people are willing to pay for it, when the celebrity is someone the buyer admires. The price reflects a felt connection, not a physical difference in the object.
Is contagion sensitivity the same across all cultures? Cross-cultural research has found similar contagion sensitivity in societies very different from modern Western contexts, suggesting it’s a fairly deep-rooted tendency in human cognition rather than a habit specific to any one culture (Apicella & Barrett, 2016).
Sources
- Rozin, P., Millman, L., & Nemeroff, C. (1986). Operation of the law of contagion in firearm avoidance and other domains. Journal of Personality and Social Psychology, 50(4), 703–712.
- Nemeroff, C., & Rozin, P. (1994). The contagion concept in adult thinking in the United States: Transmission of moral qualities and physical traits. Ethos, 22(2), 158–186.
- Nemeroff, C., & Rozin, P. (2000). The making of the magical mind: The nature and origins of sympathetic magic. In Imagining the Impossible (pp. 1–34). Cambridge University Press.
- Newman, G. E., Diesendruck, G., & Bloom, P. (2011). Celebrity contagion and the value of objects. Journal of Consumer Research, 38(2), 215–228.
- Apicella, C. L., & Barrett, H. C. (2016). Cross-cultural variation in contagion sensitivity and magical belief. Evolution and Human Behavior, 37(5), 382–388.
