Definition
Dehumanization is the perception or treatment of another person or group as less than fully human — likened to an animal, a disease, an object, a number, or vermin — so that the moral protections normally extended to people no longer apply.
The concept has two faces in the books that develop it. From the outside, dehumanization is what one group does to another: a manufactured perception, usually language-driven, that places the target beyond the moral circle. From the inside, it is what an institution does to the person inside it: a stripping away of name, possessions, and individuality that threatens the very feeling of being someone. Sapolsky's Behave maps the first face onto neural circuitry. Frankl's Man's Search for Meaning documents the second from the inside of a concentration camp. Together they show that dehumanization is both a weapon aimed outward and a pressure exerted on the self.
Why it matters
How it works
Recycled neural circuitry — the insula does double duty
Sapolsky's account in Behave starts from a striking observation about brain architecture. Symbolic and metaphorical thinking evolved so recently that the brain never grew dedicated machinery for it. Instead, evolution improvised: it co-opted ancient regions built for concrete jobs and handed them metaphorical work. The anterior cingulate, built to register physical pain, fires for social rejection too. The insula, built to expel rancid food, fires at moral violations as well. The metaphor "I felt sick when I heard what they did" is not just a figure of speech to those neurons — they really are doing both jobs.
This recycling makes the propagandist's job mechanical. If you want a population to feel that some Other barely counts as human, there is one reliable route: engage the insula, the seat of visceral disgust. Call the Tutsi "cockroaches" long enough and ordinary Hutu farmers pick up machetes. The viewer's brain has been trained to treat the target the way a tongue treats spoiled meat. Other studies Sapolsky cites push the point further: shown images of the most stigmatized groups, viewers' brains failed to engage the regions that normally register another person as a thinking, feeling agent — they processed the target more like an object than like someone.
Manufactured, not spontaneous — the role of language
Dehumanization in Behave is almost never an organic reaction. It is built, and it is built mostly with words. Repeated pairings — vermin, disease, infestation, parasite, animal — fuse a group with something disgusting until the linkage feels intuitive rather than rhetorical. That is why recognising dehumanizing language is not a literary criticism exercise; it is an early-warning system. The metaphor is the mechanism. By the time the policy arrives, the population has already been primed to greet it as common sense.
The same vulnerability that makes us susceptible to atrocity propaganda also opens a route to peace. Because the brain confuses the symbolic with the concrete, respecting an enemy's sacred symbols — a flag, a holy book, a memorial — is, biologically, an act of recognising their humanity. Symbolic gestures are not soft diplomacy; they are direct neural interventions.
Atrocity as the predictable downstream effect
Sapolsky's topic on war and peace makes the historical case explicit. The same biology that fuels atrocity also equips us for reconciliation, and the world has, on the whole, gotten better — slavery, judicial torture, child labor, and public cruelty have all retreated. But every step backward into mass violence has been preceded by the same move: place the target outside the category of people first; do the violence second. Recognising dehumanizing rhetoric in time is therefore the cheapest and earliest atrocity-prevention tool available.
Dehumanization from the inside — Frankl in the camps
Frankl's testimony in Man's Search for Meaning shows what dehumanization feels like to the person inside the machine. On the train ramp at Auschwitz he describes the "delusion of reprieve" — the condemned mind's last-minute hope that the sentence will not be carried out — and then the methodical erasure that followed: possessions taken, hair shaved, name replaced with a number, every material trace of a former life struck out. He calls what was left "naked existence."
In the entrenched phase of camp life, the pressure became continuous rather than sudden. Prisoners were herded like sheep, counted, marched, and addressed only by number. Frankl notes that the number on the list mattered more than the man it belonged to: lose the number, lose the life. Against this pressure he names a quiet act of resistance — the prisoner who refused to surrender the feeling of being an individual, and who therefore did not collapse into the collective grey mass the system was designed to produce.
The soul's weapons — beauty, humour, and inner freedom
The most surprising material in Frankl is what survives inside the dehumanized person. Even in the camps, prisoners experienced beauty — a Bavarian sunset, the mountains of Salzburg seen through a barred window — and used humour deliberately. Frankl records training a fellow prisoner to invent one amusing story a day, framing the exercise as the art of living under conditions where suffering never lifted. Humour, he writes, can afford an aloofness and an ability to rise above any situation, even if only for a few seconds. These were not distractions; they were instruments of self-preservation against an environment engineered to reduce the self to nothing.
He pairs this with a clinical observation about hope and the body. A prisoner who lost faith in the future declined and died, often within days. He records the composer F——, who died on the very date a dream had promised liberation, and a spike in deaths around a Christmas when expected release did not come. Loss of hope lowered the body's resistance and a latent infection finished the job. The inner stance was not metaphysical decoration. It was, measurably, a survival variable.
Reversing the question of meaning
The deepest move in Frankl's account is a reframing he and others had to teach despairing men. They had been asking what they could still expect from life. He taught them to invert the question and understand themselves as those being questioned by life — answerable, daily and hourly, in concrete conduct. Meaning was not a general truth to be discovered but a specific task, unique to each person and moment. Inside a system designed to dehumanize, this restored the missing ingredient that dehumanization tries to remove: the sense of being a someone with a particular responsibility nobody else can discharge.
Two races of men — the line runs through everyone
On the guards themselves Frankl refuses simplification. There were sadists, and there were guards who showed unexpected kindness — the camp commander who bought medicine for prisoners with his own money. From this he draws the line that closes the topic: there are only two races, the decent and the indecent, and they are found in every group, the boundary running through every human being. This is the answer in his book to the easy version of dehumanization that would simply flip the labels and make the perpetrators sub-human in turn. The dehumanizing logic is the disease, not a tribe to be located and demonized.
The distorted return — depersonalisation after liberation
Even rescue does not undo dehumanization cleanly. Frankl describes liberation as depersonalisation — a freedom that could not yet be felt — followed by the slower dangers of bitterness toward a world that had shrugged, and disillusionment at a fate that proved suffering had no natural limit. The mark left by being treated as less than a person does not lift on the day the gates open. Re-humanization is a process, not a moment.