Mass formation is a theory describing how large groups of people can become fixated on a single cause or narrative, losing their ability to think critically and tolerating things they normally wouldn’t accept. The concept gained widespread attention during the COVID-19 pandemic when Belgian clinical psychologist Mattias Desmet used the term “mass formation psychosis” in interviews and his 2022 book The Psychology of Totalitarianism, though the underlying ideas draw on much older traditions in crowd psychology. The term is not a recognized clinical diagnosis, and its scientific standing is heavily debated.
Where the Idea Comes From
The roots of mass formation theory stretch back to the late 1800s, when researchers first tried to explain why people behave differently in crowds than they do alone. French sociologist Gustave Le Bon popularized the idea of “group mind,” arguing that individuals in a crowd lose their sense of personal responsibility and become suggestible. Around the same time, Pierre Janet was studying how emotional trauma could cause dissociation, and Sigmund Freud was theorizing that repressed emotions could manifest as physical symptoms in individuals. These threads eventually merged into what became known as “mass hysteria,” a term that first appeared in the 1920s to describe what the Oxford English Dictionary called “deranged group mentality” or “mob-madness.”
Mass formation, as Desmet frames it, builds on this tradition but adds a specific structure. Rather than describing spontaneous crowd behavior at a protest or rally, it attempts to explain how entire societies can gradually shift into a kind of collective tunnel vision, where people willingly surrender individual judgment to a group narrative. Desmet connects this process to the rise of totalitarian regimes in the 20th century, arguing that the populations under figures like Stalin didn’t simply comply out of fear but were psychologically absorbed into a shared belief system.
The Four Conditions Desmet Describes
Desmet’s central claim is that mass formation requires four pre-existing conditions in a population before it can take hold:
- Widespread loneliness and weak social bonds. People feel disconnected from family, community, and meaningful relationships. The World Health Organization estimates that about 16% of people worldwide, roughly one in six, experience loneliness, with the highest rates among adolescents and young adults.
- A lack of meaning in life. Large numbers of people feel their daily existence has no real purpose. They go through the motions of work and routine without a sense that any of it matters.
- Free-floating anxiety. This is anxiety that isn’t attached to a specific, identifiable cause. People feel uneasy and stressed but can’t point to exactly why, which makes the feeling harder to manage or resolve.
- Free-floating frustration and aggression. Similar to the anxiety, people carry anger and resentment without a clear target. They feel something is deeply wrong but don’t know where to direct those feelings.
When all four conditions are present, Desmet argues, a population becomes vulnerable. If a narrative then emerges that names a specific threat and offers a clear strategy to fight it, people latch on. The anxiety that had no object suddenly has one. The frustration has a target. And the collective focus on this shared cause creates a powerful sense of social connection that fills the void left by loneliness and meaninglessness. People feel bonded to each other through the struggle, which makes the narrative extremely difficult to question, because questioning it means risking that newfound sense of belonging.
How It Differs From Groupthink
Mass formation is sometimes confused with groupthink, but the two describe different dynamics. Groupthink typically happens in small, defined groups: a corporate board, a political cabinet, a team of advisors. It occurs when the desire for harmony overrides honest evaluation of alternatives, and it usually involves people who already know and work with each other. The pressure is largely social, driven by not wanting to be the person who disrupts consensus.
Mass formation, by contrast, is theorized to operate at the scale of an entire society. It doesn’t require that people know each other personally. Instead, it describes a psychological shift where individuals become so absorbed in a collective narrative that they lose touch with their own experiences and reasoning. Desmet compares it to hypnosis: people in the grip of mass formation aren’t simply going along to get along. They genuinely cannot see information that contradicts the dominant story, even when it’s placed directly in front of them. Whether this comparison holds up scientifically is another question, but it illustrates the distinction he’s drawing between polite conformity and deep psychological absorption.
It also differs from simple propaganda. Propaganda works from the top down, with authorities deliberately crafting messages to manipulate. Mass formation, in Desmet’s framing, is more of a bottom-up phenomenon. The population’s psychological state creates the conditions, and leaders or narratives then fill the vacuum. The crowd, in a sense, is looking for something to attach to before anyone offers it.
Why the Concept Is Controversial
“Mass formation psychosis” is not a term recognized in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), which is the standard reference for psychiatric diagnosis. It does not appear as a disorder, a subtype, or a diagnostic code. No major psychological association has endorsed the concept as a validated framework. Critics argue that Desmet’s theory lacks empirical testing, relies heavily on analogy rather than data, and cherry-picks historical examples to fit a predetermined narrative.
Some scholars in medical anthropology take a broader view. They argue that concepts like mass hysteria, which shares intellectual DNA with mass formation, function less as precise scientific descriptions and more as screens onto which a society projects its own anxieties. In other words, labeling a social phenomenon as “mass formation” may say as much about the person using the label as it does about the behavior being described. The term became politically charged during the pandemic, when it was used primarily by critics of public health measures to argue that support for lockdowns and vaccination was irrational and cult-like. This association made it difficult to discuss the underlying psychological ideas on neutral ground.
That said, the individual ingredients Desmet identifies are well-documented psychological phenomena on their own. Loneliness, purposelessness, free-floating anxiety, and undirected frustration are all studied extensively in psychology and public health. The debate is over whether combining them into a single explanatory framework called “mass formation” adds genuine insight or simply repackages existing knowledge with a provocative label.
What Proponents Suggest as Countermeasures
Those who take the concept seriously propose several strategies for resisting or disrupting mass formation, most of which center on maintaining independent thought and genuine social connection. The recommendations include fostering cultures of open debate where dissent is welcomed rather than punished, encouraging people to question narratives and evaluate evidence rather than responding to fear, and ensuring transparency in decision-making so people understand why choices are being made.
At the individual level, the prescription is straightforward: maintain real relationships, pursue work and activities that feel genuinely meaningful, and stay willing to voice disagreement even when it’s uncomfortable. These aren’t groundbreaking insights, which is part of the criticism. The countermeasures to mass formation sound a lot like general advice for psychological well-being, suggesting that the concept may describe an ordinary vulnerability to social pressure rather than a distinct psychological phenomenon requiring its own name.
Regardless of where you land on the theory’s validity, the underlying concern it points to is real. Societies with high levels of loneliness, anxiety, and disconnection are more susceptible to polarization, manipulation, and the appeal of simplistic narratives. Whether you call that mass formation, social contagion, or just human nature under stress, the pattern is worth understanding.