‘ They deserve it for what they’re doing ’: dehumanising rhetoric as a facilitator of the recourse to violence against the defenceless

Torture has been with us for all of recorded history, often assuming an important role in juridical and legal systems. Despite a decades-long campaign, torture persists within many nations today, and is sometimes considered, or even implemented, as a policy and practice option in nations that otherwise would abjure its use. Here, we consider the possible relationships between the willingness to employ torture and psychological processes related to dehumanisation. There are multiple strands of evidence linking the use of dehumanising language against out-groups leading to violence against that outgroup. Dehumanising persons through language and policy can cause a ripple effect feeding through acts of violence and torture committed by state actors in the service of attaining and maintaining power and coercive control over minority out-groups.


Introduction
The United Nations Convention Against Torture [1] defines torture as "…any act by which severe pain or suffering, whether physical or mental, is intentionally inflicted on a person for such purposes as obtaining from him, or a third person, information or a confession, punishing him for an act he or a third person has committed or is suspected of having committed, or intimidating or coercing him or a third person…" (Article 1).Torture is absolutely prohibited under international law, and very often illegal under the domestic law of many countries, especially those countries that are signatories to the relevant international conventions on the prohibition of torture.
Torture has been with us for all of recorded human history, and is (sometimes) a recourse in democracies under stress and in authoritarian regimes alike [2,3].Torture is perhaps the most extreme form of interpersonal aggression and inhumane treatment, short of murder or genocide, because it involves deliberately inflicting 'severe pain or suffering' on a defenceless person.
Reasons for torture include punishment; coercively controlling third parties/the public; forcing abjuration of intellectual/ideological positions; coercing confessions.In the popular media, torture is typically (and inaccurately) presented as a reliable information-extraction methodology [7].Analyses of interrogational torture suggest it fails as interrogational practice because interrogational torture is an (inadvertent) assault on our core integrated social, psychological, and neural functioning.Imposing the extreme stressor states elicited by torture militates markedly against, as well as negatively affecting, our normal cognitive, affective, and physiological functioning [2,[4][5][6][7].
Here, we briefly survey some empirical possible linkages between dehumanisation and the willingness to embrace torture, either rhetorically or in policy.We define 'dehumanisation' conventionally as the denial of a person's humanity, in part, or altogether (see fuller discussion below).As such, dehumanising rhetoric regarding outgroups may, at least in part, prepare the ground for the use of torture against members of those outgroups, or lower the threshold against the use of torture.We also suggest this area is ready for further novel empirical approaches.Archival analyses may prove particularly valuable: Hassner [8], for example, has undertaken such work with archival interviews from the Spanish Inquisition, finding torture was used sparingly, with great solemnity, and only to attempt to confirm prior testimony at the end of an investigational process.
Dehumanisation is the denial of a person's humanity, in part or altogether [17].Dehumanisation involves the denial of characteristics considered uniquely human (e.g.sense of morality), or of attributes associated with human nature (e.g.interpersonal warmth) [18].Often the denial of human uniqueness to an individual or group equates humans to animals (animalistic dehumanisation, or sometimes, 'blatant dehumanisation' [19]), while the denial of human nature renders them as something akin to objects or automata (mechanistic dehumanisation).
One caveat: there are extensive literatures in legal, sociological, psychological, neuroscientific domains regarding punishment.Punishment happens after a behaviour or behaviour has occurred; torture is applied with the intention of eliciting a behaviour.Conceptually, these are very distinct, and the large neurocognitive literature on punishment is largely irrelevant to the analysis of torture.Ethical and technical concerns ensure the neurocognitive processes underpinning the decision to use cruelty, coercion, and violence against defenceless captives by individuals and groups are largely unexplored.Punishment and torture are not the same concepts, and confusing them is unhelpful.Punishment, derived from a sentence under a legal system, may involve the infliction of pain or suffering, or other deprivation of rights (such as freedom), or financial penalties, and is carried out with the intent of upholding the law and protecting society.Legal punishments are typically carried out as the result of a legal process, with specific rules and procedures designed to ensure the punishment is proportional to the offence committed, and that the rights of the accused are protected.There are legal and other tests in place to test if punishment is disproportionate (the UN Special Rapporteur on Torture has a special investigational role in this regard).

Consequences of dehumanisation
Over the last three decades, dehumanisation has been identified as an important psychological process underpinning acts of violence against outgroups [20][21][22][23].Humans appear to attribute less uniquely human characteristics to outgroups, than to their own ingroup [19,24].Dehumanisation of outgroups takes place when the perception of 'otherness' reaches an extreme, shifting from mere dissimilarity in characteristics, practices, or beliefs, to otherness 'in essence' (what might be called 'essentialist dehumanisation').
Dehumanisation has been linked to numerous negative outcomes for intergroup relations.These negative outcomes entail a decrease in willingness to forgive [25], a decline in feelings of guilt for pain and suffering inflicted during times of conflict [26], as well as a decline in willingness to help outgroup victims of natural disasters [27].Dehumanised perception is a powerful process driving intergroup discrimination and conflict [28], and legitimising aggression and violence between groups [19,29,30].
When considering how dehumanisation may facilitate acts of aggression and violence, we must consider its effects on moral cognition.When we perceive another person as dehumanised, we may be placing them outside the remit of moral consideration.This, in turn, may lead to a decreased sensitivity to their suffering and inhumane treatment [31], and might thereby facilitate acts of aggression and violence [22,28,29,32].For most people, deliberately inflicting pain on another human being will trigger considerable discomfort and moral self-sanctions [20,33,34] -dehumanisation offers a bypass through detachment from moral scrutiny by the perpetrator [35].By stripping victims of moral worthiness, and thus lessening distress associated with the experience of empathy and self-condemnation, dehumanisation may enable aggressors to engage in inhumane conduct [29,31].

The ripple effects of dehumanisation
Although dehumanisation is widely recognised as facilitating interpersonal aggression, the relationship between dehumanisation and acts of violence is not unidirectional.Instead, as Kelman notes, 'the process of dehumanisation feeds upon itself' [32].In a self-reflective vicious cycle, dehumanisation acts as both -a prerequisite for, and effect of, degrading and inhumane treatment of another human being [17].
Further testifying to the potency of dehumanisation, Kteily et al. [28] examined effects of metadehumanisation, defined as the perception of being dehumanised by an outgroup.Perceived dehumanisation of participants' ingroup led to an increase in reciprocal dehumanisation of the outgroup in question.This suggests dehumanisation may inspire reciprocal dehumanisation, leading to greater hostility between groups, thus exacerbating intergroup conflict further [28,36].

Torture and dehumanising political rhetoric
The language of leaders and elites matters: the use of phrases such as 'enhanced interrogation techniques' as an alternative to words such as 'torture' or 'coercion' normalises practices that otherwise would be found repugnant in a democracy [10,11].Torture is sometimes treated as a 'macho' talking point, as a way of differentiating one 'strongman' ruler from another.The serious human rights violations proposed, and the illegality of torture under domestic and international law are left unconsidered.[12].The language here is instructive.Trump conflates interrogational torture for information gathering with torture as punishment, both directed at an unnamed and unspecified 'they'.The 'they' is an unspecified other; not a specific, named person, but a 'they' posing a threat to the in-group; both by definition and through exclusion, the 'they' is a member of an out-group.'They' are not given a name, personhood, citizenship, or relationships with other humans being -all denials of personal identity and agency, core to the concept of dehumanisation.
Trump is not alone in the use of such language.Through the ages, dehumanisation of others has often been a prelude to policies of mass imprisonment, torture, murder, and genocide.Slaves in the Roman Empire were regarded as property and not as legal persons with protection from torture (they were, by definition, dehumanised and depersonalised by the automatic operation of Roman law [13]).In fact, their testimony was only acceptable if it was obtained via torture.Within living memory, the examples of Nazi Germany [14], and of the Khmer Rouge in Cambodia [15,16] provide testament to the widespread use of torture, in a context where dehumanising rhetoric was deliberately employed, and targeted at, individuals and groups who were to become subject to torture by these regimes.

Dehumanisation and the recourse to violence
One important line of evidence links dehumanisation with a propensity to contemplate violence against a religious or ethnic minority outgroup [19,37,38].Persons committed to a particular political identity are more likely to engage in dehumanising rhetoric and support punitive policies toward the out-group.Moreover, there appears to be a marked increase in dehumanising language in the before and after actual intergroup violence.In this case, the resort to dehumanising language also strongly predicts support for physically aggressive acts (including torture and retaliatory violence; [19].A converging analysis in the context of crime and immigrant communities by Wahlström et al. [39] finds dehumanisation-associated, violent rhetorical tropes in online language generated by extremist groups opposed to the state and in favour of immigrant deportation.Furthermore, the dehumanising language used excuses politically-related violence, and may further be associated with a motivation for violent action against agents of the state and members of immigrant communities.

Linking dehumanisation and torture
Conceptually, torture may also be understood as an act of radical 'othering' [40].By marking victims of torture as 'other', torturers create a necessary psychological divide.As Rodley puts it: "When [torture] is part of an institutional practice […] the victim is -must be -dehumanised, seen as an object…be it [as] a class enemy, a race enemy, a religious enemy, or a foreign enemy" [41].Dehumanisation appears to be a facilitating of, if not necessary, process enabling a person to inflict severe pain or suffering on another human being.
Inflicting physical pain feeds the process of exclusion and dehumanisation.For torture victims, the sensation of extreme pain becomes an experience of self-betrayal [17].The body starts to be perceived as an active source of suffering, and may eventually be seen as disjunct and foreign, further contributing to the victim's fragmentation of sense of self [42].For perpetrators, the dehumanised perception of their victims is further reinforced by witnessing and engaging in their very victimisation [32].

What are the consequences of torture?
Torture is associated with significant detrimental consequences for both victims and perpetrators [5].Survivors of torture often struggle with disconnection from their own humanity, self-destructiveness, extreme anxiety, emotional dysregulation, changes in identity, reintegration with their friends and families, as well as taking control of their life's narrative post-torture [43][44][45] (see Hárdi & Kroó for a systematic review [46]).On the other hand, mental health services find themselves also dealing with perpetrators of torture [5].For instance, adverse mental health outcomes have been documented among military personnel stationed in Guantanamo Bay: tenure at Guantanamo was positively associated with alcohol abuse, as well as symptoms of depression and posttraumatic stress disorder (PTSD) [47].Significant psychological repercussions have also been documented in soldiers who took part in abuse and torture of captives [48,49].With respect to PTSD, symptoms appear more likely to develop in perpetrators who feel regret and culpability for their actions [50].

Neurocognitive analyses of dehumanisation: (not) being felt and seen as human
We have noted above that ethical and technical concerns do not allow for the direct neurocognitive investigation of torture.However, the literature on the neural correlates of dehumanisation offers possibilities.In an early and pioneering study, Harris & Fiske [51] found judgements of extreme out-groups, such as addicts and the homeless, elicit neural responses in the insula and amygdala (consistent with disgust), and did not elicit activation of medial prefrontal cortex, suggesting that extreme out-groups are perceived as less than human.Subsequently, Bruneau et al. found that when people make judgments of dehumanisation about low-status groups, distinct neural regions are activated (compared to when people made judgments of dislike, dissimilarity, and perceived within-group homogeneity).Left inferior parietal cortex and left inferior frontal cortex were selectively modulated by dehumanisation ratings, (suggesting animalistic dehumanisation).Jack et al [52] found that humanising conditions were associated with higher activity in the default mode network (DMN), and lower activity in the task positive network (TPN).Animal dehumanising conditions showed more marked changes in regions associated with mechanistic reasoning (rather than mentalising), suggesting the DMN and TPN play opposing roles in creating a sense of moral concern.Finally, Mendez [53] suggests animalistic dehumanisation results from increased inhibition of emotional feelings and empathy, with increased activity in the inferior frontal gyrus, whereas mechanistic dehumanisation results from a loss of perception of basic human nature, with hypofunction of a mentalization network centred in ventromedial prefrontal cortex and adjacent subgenual anterior cingulate cortex.
Overall, these studies suggest judgments regarding extreme out-groups elicit disgust-related neural responses, which may lead to dehumanisation.Dehumanising others is associated with distinct neural regions, including left inferior parietal cortex and left inferior frontal cortex for animalistic dehumanisation, and posterior cingulate cortex for liking.Humanising conditions involve high activity in the DMN and low activity in the TPN; by contrast animalistic dehumanisation shows more marked changes in regions associated with mechanistic reasoning, rather than with mentalising.

Conclusions
The analysis of the relationship between dehumanisation and the practice of torture is at early stage.In numerous instances, the use of dehumanising political rhetoric, and of legal statutes, opinions, and judgments, policy discussions, and documents, as well as historical archives containing dehumanising rhetoric has been associated with subsequent overt and covert torture campaigns against dehumanised individuals and groups.Extant research suggests a bidirectional, self-reflexive relationship between dehumanisation (e.g. through dehumanising language) and acts of extreme intergroup violence.Political rhetoric can be captured from government documents and related sources, and analysed at scale using now widely-available machine learning, sentiment, and narrative analysis techniques.Relationships between political language, and policy changes (or indeed popular approbation) for the use of torture as an institutionalised practice can thereby be quantitatively explored.The obverse position needs investigation too; often, the use of torture is often shrouded in secrecy [3], and the practice hidden by what might be described as a 'collective silence' (Fischer and O'Mara [9] for a review), and therefore subject to secrecy laws, or simply a collective silence.
Through collective silence and the use of language designed to shroud violent and repugnant acts (such as 'enhanced interrogation techniques'; or 'verschärfte Vernehmung', in the same terminology employed by the Gestapo), dehumanisation may also facilitate the hiding of such violent actions undertaken against the defenceless.By refining our understanding of the psychological processes underpinning dehumanisation and acts of violence, we may identify causal relationships and thereby discover potential avenues for preventing and alleviating intergroup conflict and aggression, and the consideration of torture either in rhetoric or policy.Finally, exploring the neural bases of dehumanisation may have implications for understanding the cognitive and neural mechanisms underlying the decision to use torture against defenceless human beings.
The former president of the United States, Donald Trump, while on campaign in 2016, told a rally 'you bet your ass' that he will bring back waterboarding."Believe me, it works.And you know what?If it doesn't work, they deserve it anyway, for what they're doing […] It works, okay?It works.Only a stupid person would say it doesn't work"