What is an emotion? What is a feeling?
These are thoughts. Okay, maybe they are a great big bundle of thoughts. But they live right there between your ears.
Until, that is, you share them.
We all know thoughts can be shared. They can be written down or yelled from the rooftops, and emotions can do the same. They can be contagious, like a flu bug.
Emotional contagion is real. And it’s really powerful. It’s why a live comedy show is so much funnier than the Netflix special. And when it’s not funny, when the act bombs? The awkwardness and anxiety—that I love btw—is that much harder to handle. You can feel it with all your senses. The emotion travels through the room at the speed of sound and light, no incubation period is required.
As you walk out of the club that night, the people on the street will be infected too. The folks in line for the second show will be primed by the emotions they absorbed as you walked past them, parroting bits and fumbling punchlines.
And it’s a two-way street.
The Power of Crowds
“Comedy is like surfing,” Jerry Seinfeld said. “You can feel the wave of laughter coming, and if you catch it just right, you ride it all the way to shore. But if you miss it, you wipe out.” So, what do comedians do to increase their chances of catching a big wave? They send out the JV squad, an opening act, to warm things up a bit. A few laughs penetrate the walls of the green room as they sip on a cocktail backstage. They allow themselves to get infected as they scan the horizon for an incoming set. But it’s not just comedy clubs where emotions spread.
Ever have your dad come home after sitting in rush hour traffic? Did he need to say he was upset, or did you feel it, and avoid it, until dinner was on the table?
Ever catch a glimpse from a girl across the room? No words spoken, just butterflies. What if it’s the class bully looking at you instead? That launches the butterflies as well, they’re just flying in a different formation.
I felt this power so strongly in junior high I can still remember it with clarity. It was the spring of 1994, and as I walked from Mr. Fairbanks’ woodshop to Mrs. Fernly’s algebra, the hair on my neck stood on end.
I looked around, and the group I was with all had a similar feeling. Mrs. Fernly was teaching in a portable that year—out by the red cinder track, which meant a walk around the back side of the school where there was minimal supervision.
As a group, we were suddenly excited; it seemed like we were being pulled forward by an invisible force. And as we rounded the corner, we finally saw what was causing this internal commotion.
On the other side of the dumpsters, Daniel was beating the snot out of some unfortunate soul.
After the fact, rumors swirled, but my recollection was the kid catching a beating dropped the wrong slur in the wrong company—and skinny as he was, Daniel could out box most kids in our grade. Especially the racist ones.
Now, neither of the fighters were within sneezing distance of me or the group I was with, they didn’t infect me with a literal virus, but something was running through my veins, infecting me and my classmates.
It was an emotional contagion.
Emotions, feelings, thoughts, and ideas can travel quickly. The strong ones spread faster than the flu.
From Combat to Prison
“Psychology is more contagious than the flu.”
That’s a quote I heard from Evan Hafer on the Joe Rogan Experience. The clip blew up because it’s profound, and because Rogan paused to say how profound it was.
Hafer, a Special Forces veteran and founder of Black Rifle Coffee Company, heard the quote from Jeff Kirkham, his Team Sergeant, and was talking to Rogan about war. He was talking about losing his shit in a firefight, and how that positive or negative frame of mind can infect everyone around you.
Hold that image of Hafer, bullets flying, in your mind. The contrast between Chicken Little and a seasoned combat veteran. A warrior that stays cool, calm and collected. Rises to the occasion. What does a different psychological state do for the team? And their outcomes?
But those words, “Psychology is more contagious than the flu,” that traveled from Kirkham, to Hafer, to Rogan, to me (and millions of others), are most often attributed to Philip Zimbardo. The psychologist who gained notoriety in the years following his 1971 Stanford Prison Experiment. The study showed the world how quickly social dynamics can spread through a group, transforming perspectives and behaviors, just as Hafer had learned.
Social and emotional contagion. Panic and anxiety, worry and calm, they flow from one person to the next. But how?
How Psychology Spreads
Zimbardo was studying the psychological effects of perceived power and authority. He recruited 24 male college age students to participate in a two-week experiment. The students were randomly assigned the roles of guards or prisoners in a mock prison constructed in the basement of a Stanford University building.
The guards quickly took on the authoritarian behaviors we attribute to the profession, using psychological tools like verbal humiliation, sleep deprivation, and solitary confinement. Meanwhile, the prisoners fell into a predictable pattern of rebellion, followed by submission, and eventually despair.
The guards hid behind their newfound authority, escalating the abusive behavior, while the prisoners surrendered their freedoms, succumbing to the psychological weight of the situation.
These students could leave at any time, they knew it was an experiment. They all reported having had a sense that behaviors were escalating, but they fell into their roles, and most of them stayed.
The experiment was planned for two weeks but was cut after just six days. Zimbardo’s fiancée and fellow psychologist, Christina Maslach, intervened after witnessing how quickly conditions had devolved for the prisoners.
The findings showed us how infectious power can be, and how quickly people surrender their freedoms in an oppressive environment.
It gave us a glimpse of how quickly people can assimilate, change, and morph, to become something different. Their psychological state changed, purely based on social and environmental inputs.
At least, that was the prevailing narrative from Zimbardo.
Behind the Experiment
What he left out during his media tours was crucial: he was patient zero, he was a super-spreader. The students were assigned roles and encouraged to act the part. Their behaviors weren’t purely organic—they came from popular culture, from films like Cool Hand Luke and The Great Escape. The psychology did spread, but not quite in the way Zimbardo suggested.
This rapid transmission of behavior and attitude isn’t limited to prison experiments. We see it in corporate cultures, where new employees quickly adopt the prevailing mindset. We see it in startups that grow from scrappy innovators to bureaucratic behemoths. And we see it in brands that transform their customers from casual buyers to devoted tribes.
Understanding how psychology spreads through groups isn’t just academic curiosity—it’s essential knowledge for anyone building a team, growing a company, or trying to create lasting change in any organization. The question isn’t whether psychology will spread, but what kind of psychology we’re cultivating.
These thoughts, these feelings and emotions—they don’t just live between our ears. They flow between us, changing us and those around us, spreading faster than any virus. Emotional contagion is real. And it’s really powerful.
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