Swann's fusion theory

There are ideas that we don't just think about.
There are ideas that think of us.

They don't appear as hypotheses, nor as reasonable doubts. They arrive with the force of an absolute truth:

“That’s just how I am.”
“I’ve always been like this.”
“I can’t change.”

And the unsettling thing is not that those sentences sound convincing.
The unsettling thing is that they organize all your behavior without you realizing it.

Decisions, relationships, boundaries, repeated failures… everything begins to revolve around an internal narrative that you no longer question. Not because it's true, but because it has merged with you. It's no longer a thought: it's your identity.

Modern psychology has a precise name for this phenomenon.
And it's not a pretty metaphor. It's a measurable, replicable, and profoundly human mechanism.

Swann explained it with uncomfortable clarity: when a belief about who you are becomes entrenched, your mind begins to actively work to prove it true, even when it hurts you.

This article isn't about cheap motivation or positive thinking. It's about understanding why we defend limiting versions of ourselves, why we cling to labels that sabotage us, and why, sometimes, change is scarier than suffering.

If you've ever felt like your own story is squeezing your neck... keep reading.

Swann's theory of cognitive fusion: when the self becomes rigid

William Swann proposed an idea as unsettling as it is revealing: the self is not always flexible, adaptive, or open to change. On the contrary, in many cases, personal identity can become a rigid structure, intensely fused with the group, capable of justifying extreme behaviors. This proposal, known as Identity Fusion Theory, redefines how we understand the relationship between the individual and their sense of belonging.

Unlike traditional models of social identity, which posited a certain psychological distance between the personal self and the group, Swann's theory (Swann et al., 2009) argues that in certain contexts these two spheres can be viscerally integrated. When this occurs, the individual does not feel like part of the group: they feel like they ARE the group. This fusion entails a feeling of collective invulnerability and a willingness to sacrifice everything for the shared cause.

The context in which this theory gained traction is not neutral. It originated in the analysis of phenomena such as terrorism, fanaticism, unwavering military loyalty, and radical nationalism. From there, it spread to other less extreme but equally significant areas: personal relationships, political identity, and professional belonging. Cognitive fusion describes a psychological phenomenon with transformative power, but also destructive potential.

Self-verification: the invisible engine that protects our identity

One of the fundamental mechanisms that sustains this identity fusion is self-verification. According to Swann (1983), human beings not only want to feel good about themselves, they want to feel consistent. This need for consistency often leads people to actively seek confirmation of their own beliefs about who they are, even when those beliefs are negative or painful.

A teenager who perceives themselves as problematic will tend to interpret their failures as proof of their identity. They won't seek to disprove them, but rather to solidify them. An adult who considers themselves incapable of love will choose relationships that reinforce that idea. Self-verification isn't about self-esteem, but about stability: we prefer to be someone we know, even if it hurts us, rather than live in the uncertainty of an identity yet to be built.

This phenomenon is also observable in clinical practice: patients who reject therapeutic success, sabotage healthy relationships, or resist profound emotional change. This is not due to a lack of desire to improve, but rather to a fear of losing the identity coherence they have maintained, sometimes for decades, as a form of existential orientation.

Why do we defend negative beliefs about ourselves?

This paradox of clinging to harmful ideas becomes less strange when we understand the psychological function of identity. The self is not just a narrative about who I am; it's an emotional compass, a system of prediction and control. If someone defines themselves as "unlovable," that belief, however destructive, provides a stable framework from which to anticipate the world.

Changing that belief poses a double threat: emotional (it involves reopening wounds, revisiting traumas, exposing oneself to emptiness) and structural (it affects how one relates, works, and makes decisions). That's why many people, even with access to therapeutic tools, maintain dysfunctional identity patterns. Because identity, when it becomes rigid, acts like an anchor: it immobilizes, but it provides stability.

From the perspective of self-theory, coherence has adaptive value: it facilitates self-regulation, social judgment, and autobiographical memory. But when it merges with negative content and becomes impervious to experience, it can become an emotional trap. Cognitive fusion, then, is not just a distortion, but a defense: a sophisticated way of avoiding the internal chaos generated by dissonance.

Cognitive fusion, self-esteem, and human relations

Identity doesn't exist in a vacuum. It unfolds through relationships, is reflected in the gaze of others, and is confirmed or challenged in every social interaction. Cognitive fusion has direct effects on self-esteem and how we relate to others. When a person defines themselves entirely in terms of their group, their partner, or their professional role, any threat to that structure is experienced as an attack on the self.

This explains many extreme behaviors in romantic relationships: pathological jealousy, emotional dependency, and disproportionate sacrifices. The person isn't acting from a place of free love, but rather from the need to preserve an identity that has become trapped in the relationship. The same occurs in toxic work environments where someone becomes defined by their job, and any professional criticism is interpreted as a personal humiliation.

In these cases, self-esteem ceases to depend on internal self-evaluation and instead relies exclusively on external validation from the group or a significant other. This can generate cyclical dynamics of reaffirmation and submission, where the individual stops questioning their position, even when it is painful.

Scientific evidence: what we know today about cognitive fusion

Since its formulation, Identity Fusion Theory has been the subject of numerous empirical studies. Swann, Gómez, and colleagues (Swann et al., 2010; Gómez et al., 2011) developed measurement scales such as the Identity Fusion Scale, which allowed for the operationalization of the construct and the exploration of its relationship with variables such as extreme altruism, willingness to sacrifice, and group loyalty.

In a series of studies conducted in military and nationalist contexts (Swann et al., 2014), it was observed that individuals highly fused with their group showed a greater willingness to risk their lives in defense of the collective, even when there was no direct threat. This pattern held true in samples from different cultures and ideological contexts.

Other research (Fredman et al., 2017; Buhrmester et al., 2012) has shown that merging with radical groups can predict participation in acts of political or religious violence, and that the feeling of personal agency (the belief that one can make a difference within the group) increases the likelihood of extreme behaviors when the individual is fused.

However, there are also nuanced findings. Not all forms of fusion lead to violence. In pro-social contexts, fusion can motivate altruistic actions, civic participation, or the defense of human rights. The key seems to lie in the ideological and moral content of the group with which the self has merged.

Is it possible to stop being what we believe ourselves to be?

The final question this theory leaves us with is not technical, but profoundly existential: can a person cease to be what they believe they are? Can they distance themselves from a rigid identity without falling into a void?

From the perspective of psychological flexibility (Hayes et al., 2006), the answer is yes, but not easy. It involves dismantling cognitive fusion, reconnecting with personal values not mediated by the group, and tolerating the uncertainty of change. It requires time, support, and the gradual construction of a new, more flexible identity narrative, more open to nuance and less subject to control.

It's not about destroying the self, but about making it less rigid. About allowing identity to be a process, not a label. Being consistent doesn't mean repeating patterns, but about honestly living who you are now, not who you were or what others dictated you should be.

Because sometimes, wanting to change isn't enough. You have to dismantle the psychological framework that has sustained a certain idea of yourself for years. And that, as theory and clinical practice show, isn't a leap, but a journey. A process as human as it is complex: becoming someone new without betraying yourself in the process.

EXTRA: When I am the team: Swann's theory applied to football fanaticism

In football, the boundary between preference and identity blurs with unsettling ease. It's not just about supporting a team, but about being that team. Expressions like "I've been a Real Madrid fan since I was born," "being an Atlético fan is suffering," or "Barça is more than a club" don't function as harmless metaphors, but as stable identity statements. From Swann's perspective, a phenomenon of cognitive fusion occurs here: the belief ceases to be an evaluable thought and becomes integrated into the core of the self.

When this happens, the psychological system automatically activates self-verification mechanisms. The fan doesn't seek to understand the game objectively, but rather to confirm that the internal narrative remains valid. Victories reinforce grandiose identities; defeats, far from weakening them, can solidify identities based on sacrifice and suffering. In both cases, the result fulfills a precise psychological function: protecting the coherence of the self.

The most paradoxical aspect is that even emotionally negative experiences can strengthen the fused identity. Shared suffering increases the sense of belonging and elevates the symbolic value of the bond. Leaving the team would not be a simple change of taste, but a direct threat to the continuity of the self. From Swann's perspective, the emotional cost becomes an argument for maintaining the identity, not against it.

This fusion also explains the intensity of rivalries and hostility toward the “other.” When the team becomes part of the self, the rival ceases to be a sporting opponent and comes to represent a symbolic threat. External criticism is experienced as personal attacks, which facilitates defensive responses, dehumanization of the adversary, and, in extreme cases, aggressive behavior. It is not football itself that generates violence, but rather the rigid identity that emerges when cognitive fusion becomes dominant.

From a psychological perspective, the difference between intense passion and fanaticism lies not in emotion, but in flexibility. When one's identity allows for distance, criticism, and nuance, the connection is healthy. When it doesn't, the individual ceases to engage with the sport and begins to defend a particular version of themselves. And there, as Swann warned, the mind stops seeking truth and begins to protect its identity.

The refuge of us: why merging is so comfortable

Merging is not a system failure, but an efficient psychological solution. Individual thinking involves doubt, ambiguity, and internal conflict. In contrast, group identity offers something the mind deeply values: clarity and belonging. When the "I" dissolves into a "we," many decisions cease to feel like decisions; they have already been made.

According to Swann's theory, this comfort arises because the group provides already validated identity structures. Beliefs do not need to be defended individually: they are reinforced by consensus, symbols, and rituals. Defending them is to defend the coherence of the self without exposing oneself to the risk of individual error.

Furthermore, the group shares the psychological responsibility. If an idea fails, the failure isn't solely mine. This dilution of the emotional burden makes groupthink safer than independent thought. Cognitive fusion occurs when this safety becomes rigid and critical thinking is no longer necessary to maintain identity.

That's why defending "us" feels so comfortable. It's not a lack of thinking ability, but rather psychological economy. The mind chooses the path that reduces internal friction, even when that path limits freedom of thought.

References

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