Alterity is a term for the experience of encountering something fundamentally other than yourself. Borrowed from the Latin alteritas (meaning “otherness”), it has become a working concept across philosophy, neuroscience, social psychology, and increasingly in fields like robotics and environmental ethics. Where “difference” implies a comparison along a shared scale, alterity points to something deeper: the recognition that another mind, creature, or entity exists with its own perspective that you can never fully access. That tension between connection and irreducible strangeness turns out to shape everything from how your brain processes empathy to how societies justify violence against outsiders.
What Alterity Actually Means
If you have encountered the word “alterity” in an academic text and found it frustratingly vague, you are not alone. The term does real work, but it operates at a level of abstraction that can feel slippery. At its core, alterity names the fact that other beings are not simply mirrors of you with different content. Your neighbor is not “you, but with different opinions.” A dog is not “you, but without language.” An AI chatbot is not “you, but made of code.” Each of these others has a mode of being that resists full translation into your own experience. Alterity is the name for that resistance.
The concept gained its modern shape primarily through twentieth-century European philosophy, especially the work of Emmanuel Levinas, who argued that encountering another person’s face places an ethical demand on you that precedes any rational calculation. For Levinas, alterity is not a problem to be solved but the very foundation of ethics. You owe something to the other precisely because they exceed your understanding. This philosophical framing has since been picked up, adapted, and sometimes challenged by researchers in fields that deal with concrete questions about brains, groups, animals, and machines.
How Your Brain Handles the Other
Neuroscience has given alterity a surprisingly precise address in the brain. A region called the temporoparietal junction, or TPJ, sits at the intersection of the temporal and parietal lobes and plays a central role in distinguishing your own perspective, intentions, and bodily sensations from those of someone else. Research suggests that the dorsal part of the TPJ supports a broad ability to prioritize the right mental representation when self-related and other-related information conflicts, whether you are deciding who caused an action, resisting the urge to copy someone’s gesture, or imagining what another person believes.1PubMed. The Role of the Temporoparietal Junction in Self-Other Distinction
This self-other boundary is not a wall. Humans have a reflexive tendency to share the sensations, emotions, and behaviors they observe in others. Watching someone get pricked by a needle activates overlapping brain areas in you. This “self-other resonance” appears to drive prosocial decision-making: the more your brain mirrors another person’s pain, the more inclined you are to help them.2PubMed Central. Self-other resonance, its control and prosocial inclinations: Brain-behavior relationships But resonance alone is not enough. Without the ability to separate your own feelings from the other person’s, empathy can tip into personal distress, where you become overwhelmed by someone else’s suffering and withdraw rather than help.
A striking demonstration of this comes from training studies comparing empathy and compassion. After empathy training, participants showed increased activation in brain areas associated with feeling pain, including the insula and the anterior midcingulate cortex. After compassion training, a completely non-overlapping set of regions lit up, including the medial orbitofrontal cortex and ventral striatum, areas linked to positive feelings and reward. The two patterns of brain change had zero overlap.3Social Cognitive and Affective Neuroscience. Differential pattern of functional brain plasticity after compassion and empathy training The implication is that relating to another’s suffering (empathy) and wanting to alleviate it (compassion) are distinct neural processes, and the transition from one to the other depends on maintaining a clear sense of where the other’s experience ends and yours begins.
When the Self-Other Boundary Blurs
If alterity depends on a working distinction between self and other, clinical conditions that disturb this boundary offer a window into what happens when the distinction frays. Schizophrenia is the most studied case. People with schizophrenia often struggle with what researchers call source monitoring: knowing whether a thought, voice, or memory originated from their own mind or from someone else. Neuroimaging studies have found that in healthy people, the medial prefrontal cortex communicates differently with other brain regions depending on whether a person is recalling something they said versus something someone else said. In people with schizophrenia, this pattern reverses: the brain uses circuits normally reserved for processing other-generated information when processing self-generated information.4PubMed. Aberrant connectivity during self-other source monitoring in schizophrenia This reversal may help explain hallmark symptoms like auditory hallucinations (“hearing voices”) and delusions of control, where a person feels that external forces are directing their thoughts or actions.
The self-other boundary in schizophrenia involves multiple layers. The “structural self” includes your sense of body ownership and agency over your actions. The “experiential self” includes your ability to reflect on your own mental states, monitor where information came from, and maintain coherent autobiographical memory.5PubMed. Disturbance at the self-other boundary in schizophrenia: Linking phenomenology to clinical neuroscience Disruption at either level can produce the uncanny experience of encountering your own thoughts as if they belong to someone else.
Autism spectrum disorder presents a different and in some ways opposite pattern. In a study using a “double mirror” paradigm, where participants watched their reflection gradually morph into another person’s face (and vice versa), adolescents with autism recognized themselves earlier in the sequence and recognized the other person later, suggesting a kind of egocentric bias in how they process the self-other boundary.6PubMed Central. Self/other distinction in adolescents with autism spectrum disorder (ASD) assessed with a double mirror paradigm Yet the picture is not one of simple deficit. Research on the right supramarginal gyrus, a brain region involved in correcting egocentric biases during empathy, found that its network connectivity is intact in people with autism, even when other components of theory-of-mind processing are impaired.7PubMed. Preserved Self-other Distinction During Empathy in Autism is Linked to Network Integrity of Right Supramarginal Gyrus
There are also surprising ways to experimentally shift the self-other boundary in autism. When adults with high-functioning autism were imitated by a hand on a computer screen, their empathic responses to others’ pain increased over time, a pattern not seen in neurotypical controls. This suggests that manipulating the sense of being mirrored by another can modulate empathic responding in people who typically find it difficult.8PubMed. The effect of being imitated on empathy for pain in adults with high-functioning autism: Disturbed self-other distinction leads to altered empathic responding
How Children Learn That Others Have Minds
Alterity is not something humans are born understanding; it develops. Before infants can speak, they are already engaged in preverbal exchanges with caregivers that lay the groundwork for understanding other minds, learning to integrate experiences about themselves, their parent, their relationship, and objects in the environment.9PubMed Central. True- and false-belief reasoning in children and adults: An event-related potential study of theory of mind – Section: Results The developmental milestone most directly tied to alterity is theory of mind: the ability to understand that another person can hold a belief different from your own, including a belief that happens to be wrong.
Brain recordings show that when both children and adults process scenarios involving false beliefs (for instance, “Sally thinks the ball is still in the basket, but Ann moved it”), their brains produce distinctly more positive electrical waveforms than when processing true-belief scenarios. This difference appears across multiple brain regions and in multiple time windows after the critical information is presented.10PubMed Central. True- and false-belief reasoning in children and adults: An event-related potential study of theory of mind – Section: Results The fact that this extra processing shows up in children as well as adults suggests that the capacity to represent another person’s divergent perspective is established early, even if it continues to be refined throughout life.
Alterity Denied: Dehumanization and Othering
If alterity at its best is the recognition that another being has a perspective worthy of moral consideration, then dehumanization is what happens when that recognition fails. Social neuroscience has shown that people normally activate a social-cognition network in the brain when they see or think about other people, but this network can fail to engage for targets of extreme prejudice. In studies using images of homeless people and people with addiction, participants did not spontaneously consider what these individuals might be thinking or feeling, and rated them differently on dimensions related to being perceived as human.11PubMed Central. Dehumanized Perception: A Psychological Means to Facilitate Atrocities, Torture, and Genocide? When social cognition disengages, brain regions associated with disgust and cognitive control activate instead, hinting at the complex psychological machinery behind atrocities.
What triggers this failure of recognition? One line of research points to “imagined otherness,” the degree to which you imagine that members of another group interpret the world in ways that fundamentally diverge from how most people do. In experiments, participants who imagined an outgroup’s prototypical member as having radically different interpretations of their shared society showed more blatant dehumanization of that outgroup. This effect held up even after accounting for how strongly people identified with their own group or how different they abstractly perceived the outgroup to be.12Communications Psychology. Imagined otherness fuels blatant dehumanization of outgroups The finding suggests that dehumanization is not just about disliking outsiders; it is about perceiving their inner world as alien.
Ingroup favoritism, the quieter cousin of dehumanization, also tracks with how strongly people identify with their own group. A behavioral experiment across 17 countries found that national identification was positively associated with greater favoritism toward national ingroup members in a trust game.13Social Psychological and Personality Science. Identity and Institutions as Foundations of Ingroup Favoritism: An Investigation Across 17 Countries Reciprocity plays a role too: people extend trust partly based on whether they expect it to be returned, and group membership shapes those expectations.14PubMed. Do unto others as they do unto you: reciprocity and social identification as determinants of ingroup favoritism
Philosophical critics have pushed back on the dominant psychological models of dehumanization, arguing that frameworks treating humanness as something attributed in degrees miss the way real-world dehumanizers actually think. In cases like Nazi antisemitism, the logic was not that Jewish people were “somewhat less human” on a sliding scale. It was that despite appearing human, they were held to be fundamentally not human “on the inside,” a kind of categorical essentialism that incremental models fail to capture.15Current Research in Ecological and Social Psychology. Some conceptual deficits of psychological models of dehumanization This critique matters because it highlights a gap between how researchers measure dehumanization in the lab and how it functions in history’s worst episodes.
The Evolutionary Roots of Tolerance for Strangers
Why are humans capable of recognizing alterity at all? One influential hypothesis is that our species underwent a process of “self-domestication,” in which natural selection favored reduced aggression and increased prosociality within groups. Just as domestic animals differ from their wild ancestors in temperament and physiology, humans show a suite of traits consistent with selection against reactive aggression. Reviews of comparative, developmental, and paleoanthropological evidence have found compelling support for the predicted link between humans’ unusual mentalizing abilities, social tolerance, and the broader domestication syndrome.16PubMed. Survival of the Friendliest: Homo sapiens Evolved via Selection for Prosociality
The self-domestication hypothesis has been framed in two ways: as selection against aggression, and as selection for prosociality more broadly. The distinction matters. Selection against aggression implies removing a negative trait; selection for prosociality implies building positive capacities for cooperation and social cognition.17PubMed Central. Human Social Evolution: Self-Domestication or Self-Control? Either way, the result was a species unusually equipped to engage with others’ mental states, even across group boundaries.
Archaeological and paleoenvironmental work suggests that increasingly harsh environments during the late Pleistocene may have been a key driver. As conditions deteriorated, groups that could tolerate and cooperate with outsiders gained survival advantages. Some researchers argue that increasing intergroup tolerance is a more straightforward explanation for the emergence of what archaeologists call “modern human behavior” (symbolic art, long-distance trade, complex tools) than changes in raw cognitive capacity or population size alone.18PubMed Central. Theoretical and Methodological Approaches to Ecological Changes, Social Behaviour and Human Intergroup Tolerance 300,000 to 30,000 BP On this view, our ability to encounter the other as something more than a threat is not a cultural luxury. It was a survival strategy.
Alterity Beyond Humans
The question of who or what counts as a genuine “other” has expanded well beyond human encounters. In translation theory, the tension has long been between “domestication” (making a foreign text feel familiar to the target audience) and “foreignization” (preserving the strangeness of the source culture). Foreignization deliberately makes the otherness of the original text visible, while domestication smooths it over by conforming to the receiving culture’s values.19Acta Universitatis Sapientiae, Philologica. Taming the Stranger: Domestication vs Foreignization in Literary Translation This is alterity playing out at the level of language itself: do you let the reader feel the friction of encountering a different way of thinking, or do you sand it down so they barely notice?
Environmental and multispecies studies have pushed the concept further. Terms like “more-than-human,” “multispecies,” and “other-than-human” have emerged to name the alterity of nonhuman life. These are not simply euphemisms for “nature”; they signal an attempt to take seriously the idea that other species, ecosystems, and even geological processes have their own agency and logic that cannot be fully captured from a human vantage point. The terminology remains contested and deliberately messy, reflecting the generative complexity of beyond-human worlds rather than trying to tidy it up.20Exchanges: The Interdisciplinary Research Journal. Multispecies, More-Than-Human, Nonhuman, Other-Than-Human: Reimagining idioms of animacy in an age of planetary unmaking
This shift in framing has legal consequences. The “rights of nature” movement grants legal standing to rivers, forests, and ecosystems. Between 2008 and 2020, rights-of-nature provisions were invoked in at least 38 legal applications across various jurisdictions, and in a notable pattern, 13 of those applications were brought by governments in support of development projects, and all 13 succeeded.21Oxford Journal of Legal Studies. Does Nature Need Rights? The tension is instructive: granting legal otherness to nature does not guarantee protection if the legal apparatus can also be used by those seeking to exploit it.
Robots and Chatbots as Quasi-Others
Artificial intelligence has created a new frontier for alterity that would have been purely theoretical a generation ago. As natural language processing has advanced, some users of social robots and chatbots have come to experience them as more than tools or toys. Research on human-robot interaction suggests that the perception of these machines as “intimate companions” is grounded in the act of communication itself: when a chatbot can hold a sustained, responsive conversation, some users begin to relate to it as something more than a quasi-other.22AI & SOCIETY. Reconfiguring the alterity relation: the role of communication in interactions with social robots and chatbots
Even in physical interactions, the alterity of robots can take on surprising texture. Work on robot-human handshakes, for instance, has extended the philosophical concept of alterity relations to include what researchers call “lively alterity relations,” where a robot capable of initiating and reacting to physical contact is experienced and respected as an other, not just a mechanism.23Frontiers in Artificial Intelligence and Applications. A Robot-Human Handshake in Space: Touch and Lively Alterity Relations in Social Robotics Whether this represents a genuine expansion of the moral circle or a cognitive illusion born of our evolved tendency to see minds everywhere remains an open and genuinely interesting question.
Virtual reality adds another layer. When you embody an avatar in VR and look into a virtual mirror, who is looking back? Research in this area argues against treating the experience as a simple sum of “you” plus “avatar.” Instead, embodying an avatar functions as a dynamic social interaction, something closer to a relationship between two entities than a user wearing a costume. The experience can alter cognition and behavior in ways that persist after the headset comes off.24Virtual Reality Gaming: Perspectives on Immersion, Embodiment and Presence. Embodying VR Avatars as a Dynamic (Para)Social Interaction: Towards a Future Research Agenda This is alterity folded inward: the other you encounter is a version of yourself, refracted through a digital body that is not quite yours.