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Arguing about justice

Axel Gosseries
Philippe Vanderborght

Love not war. On the chemistry of good and evil

Paula Casal


Este artigo presenta unha hipotese novidosa sobre a orixe dalgunhas caracteristicas moralmente relevantes atopadas en hominidos, elefantes e alguns cetaceos, como son o auto-conecemento, e a capacidade de asumir a perspectiva dos outros e respostar as suas necesidades. A hipotese relaciona esas caracteristicas con altos niveis de investimento materno e a oxitocina. A seguir, o artigo explora as implicacions eticas da hipotese e outros achadegos en relacion a oxitocina e a testosterona. Comeza coa analise da conexion entre a oxitocina e a moralidade, e a testosterona e o crime, e remata con algunhas propostas para re-desenar as institucions democraticas e mellorar xeneticamente a humanidade que tenen en conta as hormonas.

Note de l’auteur

For detailed comments I thank Axel Gosseries, who encouraged me to contribute a daring paper outside my usual field to celebrate Philippe's birthday, Arcadi Navarro, and Andrew Williams. For biological discussion, I thank Jaume Bertranpettit, Robin Dunbar, Carmen Mate, Eduardo Robredo, and Frans de Waal.

Texte intégral

For Philippe, a calm and caring, charitable interpreter,
with plenty of oxytocin.

1Many people envision the dawn of humanity like Kubrick. The first minutes of 2001 – released in Europe in May 1968 – show a group of hominids finding a waterhole. Shortly after, another group arrives and expels the first from its little paradise. One of the defeated apes finds a femur and, returning like an avenging angel, smashes the skull of the leader of the opposition, and victoriously throws the femur in the air. In a few seconds representing millions of years, the rotating bone turns into a rotating spacecraft.

2I never believed ’war is the father of all things’ but lacked an alternative image to Kubrick’s. Thirteen years’ involvement with the Great Ape Project, however, has made me look at that testosterone-filled, skull-smashing Adam very differently. It gave me time to reflect on the role oxytocin-flooded mothers may have played in the evolution of language, morality, food gathering and processing techniques and civilisation more generally. The paper explains the relevance of hormones and evolution to a variety of issues of ethical concern. I apologise for the over-simplification that space restrictions necessitate. I also hope not to offend, and intend only to share some findings that seem important in order to learn more about their plausibility and implications.

Maternal investment: the pattern

  • 1 This is why Marc Hausers claims to have proven that tamarinds (tiny monkeys born as twins, reachin (...)
  • 2 The fact that length of pregnancy tends to correlate with size may contribute to explaining the pat (...)

3I never expected to devise a plausible biological hypothesis. However, by focusing on Lockean persons (intelligent, self-aware creatures that can think of themselves in different times and places) (Locke 1995: 246-56) I have spotted a pattern that seems not to have yet struck any of the biologists I have read or consulted, including Frans de Waal and Robin Dunbar (Casal 2010, 2011). My conjecture is that, at least among mammals, some morally relevant properties, such as self-awareness or ability to take the perspective of others and respond to their needs, correlate with degree of maternal investment – which only in very long-living species is above the relevant threshold for these properties to emerge. For example, the Gallup tests for mirror self-recognition was passed by elephants and orcas (who can live up to 80 and 90 years) (Brault & Caswell 1993) and bottlenose dolphins and hominids (who can live up to 45-60).1 These species pregnancies are (i) almost invariably singleton, (ii) extremely long (22 months for elephants, 18 for orcas, 12 for bottlenose dolphins, 8-9 for hominids)2 and (iii) very infrequent (average birth intervals are 8 years for orang-utans, 5 for orcas, chimpanzees and bonobos, and 4 for humans, gorillas and elephants (Galdikas & Wood 1990). Maternal investment continues through years of lactation (7 for orang-utans, 5-6 in other apes, 2-4 for elephants and cetaceans), which is followed by many more years of care, protection, education and cultural transmission, extending into adolescence.

4Females’ lasting usefulness is responsible for the unique phenomenon of menopause: only humans, orcas and elephants live long after fertility ends. Whilst most species have very large numbers of offspring, and care proportionally less for each, mammalian persons occupy the other extreme of the spectrum. They all have long-term emotional memory, highly unusual imitative, linguistic, mathematical, and problem-solving abilities; they all carry corpses for days or weeks – with elephants and gorillas also burying them – and only elephants, hominids and some cetaceans (orcas, bottlenoses, beluga, Risso, sperm, humpback and fin whales) are known to have spindle neurons like us.

Maternal investment: the links

5What is the relationship between these remarkable facts? Biologists do not have a collective name for all mammalian persons, which can give us a clue. My suggestion is that a huge maternal investment is essential to understanding these species and civilisation itself. It requires large quantities of oxytocin, causing maternal love, empathy, altruism, and the patience required for cultural transmission.

6Females’ lesser strength and far larger nutritional needs resulting from prolonged pregnancies, lactation and infant nutritional dependency impose a greater need to resort to technological innovation. And if we take the most photographed examples of tool use, we see that it is overwhelmingly female chimps that practice the arts of termite fishing or sweeping; female gorillas that measure the depth of rivers with a stick, and female dolphins that manipulate air rings or use sponges to protect their noses while feeding. Female chimps would not kill a monkey even when hungry – whilst males terrorise them and kill them for fun – and so had to develop various nutrition-improving techniques, essential to female reproductive success. For whilst males’ reproductive success depends on access to females, female´s success depends on access to food. As a result, while males are more likely to obsess with sex and power, females focus on offspring and nutrition (Emlen & Oring 1977). Wrangham (2009) argues that female food preparation is the key to both our anatomical and cultural evolution.

7Females not only invent new ways of obtaining and preparing food, but are the ones that teach those techniques to their offspring. Female chimps even develop teaching techniques, dividing tasks into exercises the young repeat (Boesch 1991). Language is extremely useful to educate the young as well as to protect them from skull-smashing through alliance-building. It is, then, unsurprising that females learn to speak earlier, talk faster, talk more, and derive more political and health benefits from conversation (Brizendine, 2006: 62ff, Dunbar 2010: 73ff) or that motherese is thought to be the origin of language and music (Falk 2009). Mother-infant constant communication provides the reassurance required for sanity, the security required for immediate survival and the intensive education required for long-term survival and cultural transmission.

8Since such a high level of investment is worthwhile only if individuals survive long after education is complete, all mammalian persons are longlived. The role of spindle neurons is not yet well-understood but we know that there is a connection between longevity and size and that spindle neurons have been found only in large brains, perhaps forming a sort of fasttrack. The last remarkable feature of these species – death rituals – also fits the picture well. Having invested massively in an offspring, and being predisposed to sacrifice further still, mothers cannot simply move on when their infant dies. Consequently, they make repeated attempts to resuscitate them, and need time to lose hope and let go. Females that may have protected, or even fed, the dead infant empathise, and the whole group slows down to permit the grieving mother’s corpse-carrying.


9Why should ethicists be interested in any of this? One reason concerns its implications for the moral status of mammalian persons. Another concerns its implications for various gender-related questions concerning, for example, reproductive autonomy, discrimination against males in child-care professions, and intra-household distribution. Here I shall explore some less familiar issues.

10I start by noting that explaining the common features of mammalian persons could offer some clues about the origin of morality itself. In species requiring huge maternal efforts, the most caring and self-denying mothers achieve greater reproductive success, with females becoming more caring and self-denying over time. To ensure mothers perform all the required tasks with perseverance and patience even when stressed or ill, nature has designed them to feel an immense love for their infants. Because of its intensity, the caring impulse spreads to anything that resembles their offspring, making all creatures with disproportionally large heads, hesitant steps and incompetent vocalisations seem adorable. The caring impulse extends to any creature that stumbles calling for its mother, and then to any vulnerable and needy individual.

11Nature activates this impulse in females through oxytocin, which not only triggers labour but then causes mothers exhausted by the birthing effort to respond lovingly to the irritating calls of their newborns, providing them with milk, with breastfeeding producing more oxytocin, contractions and pain. Oxytocin increases trust and empathy and facilitates the interpretation of body language to read the baby’s mind. In these early days, survival may depend on the correct interpretation of very subtle signs, and being responsible for many hours of mother-baby contemplation, oxytocin may be the one chemical that is more closely connected to morality, assisting in our adopting the perspective of others and responding to their needs.

12The female bonobo Kuni, for example, who stretched the wings of a stunned starling, carried it to the top of the tallest tree, and cared for it all day until it flew (de Waal 2005: 2), demonstrated an ability to respond to needs she never had. These actions sometimes come at great cost, as when female chimp Washoe risked her life to rescue a drowning youngster she hardly knew (Fouts 1993: 29), when female elephants save drowning infant rhinos despite repeated rhino charges, and when female cetaceans engage in altruistic interspecies protection against sharks. Interspecies altruism is also largely female in the human species, where animal protectors are mainly female and animal torturers are mainly male. The same applies to the adoption or fostering of orphans, the feeding of mothers and grandmothers who have become too old or sick to feed themselves, and to other practices like comforting the bereaved, calming down those about to fight, and initiating reconciliations between contenders after a fight. Amongst mammalian persons, those providing care, valuing peace, and going the many extra miles for it are overwhelmingly female. We see this in neonates, with girls being more responsive to tears and other expressions of pain shortly after birth (Brizendine 2009: 41, 43).We see it in childhood, with female chimps rocking sticks to sleep while males play violent games. We even see it in entire species, in the male-dominated chimpanzee society, with homicide, genocide, infanticide and generally high levels of aggression, and the female-dominated bonobo society, where not a single instance of murder has ever been observed.


13Another reason why ethicists should be interested in these matters concerns the importance of understanding evil. In his recent Zero Degrees of Empathy, Baron-Cohen (2011) defines evil as ”the absence of empathy”, and analyses Nazi experiments – like amputating and then re-attaching hands the wrong way just to see what would happen – and other horrific cases of cruelty around the world. He notes, however, a crucial difference between two non-empathic groups, both of which are mainly male: those in the Asperger and autism spectrum, and the psychopaths. Those is the first group, identified by Baron-Cohen with ”the extreme male brain” in The Essential Difference (2003), lack empathy and trust, abilities to read body language or other minds, or take others’ perspective. Their compulsive rule-following, however, saves them from becoming evil. For example, they would not tell a lie, no matter what; and so, as in the film My Name is Khan, can even be ”super-moral”. Both groups, however, share a lack of empathy and most also share a male brain, the emergence of which Brizendine describes as follows:

until eight weeks old, every fetal brain looks female – female is nature’s default gender setting. A huge testosterone surge beginning in the eighth week will turn this unisex brain male by killing off some cells in the communication centers and growing more cells in the sex and aggression centres (Brizendine 2009: 36).

14A consequence of this is that

the testosterone-formed boy brain simply does not look for social connections in the same way a girl brain does. In fact…autism spectrum disorders and Asperger’s syndrome are eight times more common in boys. Scientists now believe that the typical male brain… gets flooded with testosterone during development and somehow becomes more easily socially handicapped. Extra testosterone…may be killing off some of the brain’s circuits for emotional and social sensitivity (Brizendine 2009: 47).

15Unfortunately, the Khan-types are less numerous than the serial killers, torturers, rapists and child molesters who also are overwhelmingly male.

16Consider, for example, the following chart provided by Wilkinson & Pickett (2009: 132) in a book which attributes a sweeping range of social ills to economic inequality rather than testosterone.

17According to this chart, women are so unlikely to murder that they are virtually equally unlikely to do so at age four, fourteen or forty. There is by contrast a shocking coincidence between violent crime in males and the surge of testosterone in adolescence. The chart makes sense when we learn the very same hormone causing men to be hairy, bald, strong and thick-skinned, makes them prone to risk-taking, aggression, sexual preoccupation, and insensitivity to others’ feelings – a rather scary combination.

18Just as intense love for our offspring can make us care for creatures quite unrelated to us, intense sexual desires can also extend to all sorts of targets. These include individuals that are uninterested, terrified or dead, members of other species or subspecies – in the case of humans including not only farm animals (Kinsey & al. 1948) but also Neanderthals (Green & al. 2010) – and even the very same offspring that inspire maternal self-denial.

19It is striking to see how much attention ethicists have given to testosterone in connection to muscle development in sports, and how little they give to its role in rape, child-abuse, battery, harassment, kidnapping, murder, war and genocide. If the correlation is as strong as some scientists suggest, this raises important issues. For example, should we think of testosterone as an involuntary injected drug that diminishes the agent’s responsibility by instilling certain propensities? Should we employ a theory of responsibility which calculates liabilities by comparison to a reference group (e.g. Roemer, 1995), and conclude that an individual was not that violent for a male? Or should we instead adopt a deterrence perspective, and focus on those that most need deterring (young males), and find what would actually dissuade them?

20Impeding reproduction (through prison and optional drug treatment) for sexual criminals could be the most effective deterrence if rape – as Thornhill and Palmer (2000: esp. 165) have argued – is an adaptation to spread one’s genes. In principle, rape could then be as genetically eliminable as any inherited disease. In mammalian persons, however, rapists do not always target fertile females. Male elephants, for example, may target infants or rhinos, and humans rape males and sometimes kill their female victims, eliminating any chance of conception. And so, instead of (or besides) an adaptation to pass one’s genes, rape among mammalian persons may be a side-effect of males being strong, aggressive, extremely sexual and less sensitive to the feelings of others. More importantly, as Thornhill and Palmer accept, certain events in individuals’ histories may make a crucial difference to their acting in these disturbing ways. For example, many serial killers and other psychopaths lacked maternal love or suffered physical or sexual abuse themselves.

21This is the most common life history in the case of female criminals. According to the US Department of Justice 1993-97 data, 98% of sexual offences, 97% of robberies, and 89% of aggravated assaults were committed by males (USDJ, 2000). Of the tiny minority of female inmates, 60% had undergone sexual abuse, and 40% were perceived by the victim to be under the influence of drugs or alcohol. This is also Baron-Cohen’s clinical experience. His typical non-empathic female patients lacked maternal love and/or were raped or abused as children. So evil can be traced to testosterone either directly as in the chart, or indirectly because being sexually abused can also make females capable of it.

Gerontocracy and Gynocracy

22Invoking female attitudes to suffering and conflict in A Darwinian Left, Peter Singer advocates electing more female politicians on consequentialist grounds. In 'The Disenfranchisement of the Elderly and Other Attempts to Secure Intergenerational Justice' (1998) Philippe Van Parijs introduces his Rawls-Machiavelli project via some unorthodox methods to promote distributive justice. The idea of disenfranchising or otherwise reducing the relative political power of the elderly draws on a fear that the elderly may have a short-term bias because they will not be around long. Younger voters, however, are also more likely to vote for younger candidates, which will make for even more testosterone-fuelled legislative bodies. If, as it seems, we will continue to be ruled by men, the above chart seems to favour gerontocracy. The same attitudes to risk, conflict resolution and the suffering of others that leads the young men in the chart to favour violent solutions to their problems could be collectively deleterious. Moreover, controlled experiments employing the ultimatum game, found that whilst spraying oxytocin increased generosity (Zack at al. 2007), administering testosterone causes people to make meaner offers, and increased their readiness to punish those who did not delivered what they wanted (Zack et a. 2009).

  • 3 Like Borat and Bruno, Ali G is a character created by Sacha Baron Cohen, a comedian not to be confu (...)

23Inspired by the true Machiavellian Ali G,3 who served a drug-laced tea at the United Nations that made sworn enemies sign peace and cooperation treaties, one might be tempted to place air-fresheners full of oxytocin in parliaments and serve testosterone-reducing spearmint tea. Leaving practical matters aside, however, it is unlikely that these measures could compensate for the shortage of female representatives or for the filter mechanisms that often favour the election of females who are masculine in the relevant respects.

24Regarding future generations, it is difficult to be confident that young men – who some car insurance companies charge more because their risk-taking attitude causes them to crash more often and damagingly – will take the most cautious, and cooperative rather than competitive, attitude towards climate stability. Van Parijs himself cites research showing that children are better served when social benefits are channelled through women, and perhaps female parliaments will reduce our reasons to worry about age. According to ’grandmother theory’, female humans, orcas and elephants survive both males (by three decades in the case of orcas) and menopause (by several decades in all three cases) because of the care they provide for the offspring of subsequent generations. Like bonobos, both elephants and orcas live in matriarchal societies, which at least in elephants are clearly gerontocratic. They actually follow Van Parijs’s more abstract principle, since in their communities those members who care most for the coming generations are ruling.


25Robert Sparrow (2010) has argued that if we favour genetic enhancement to improve the quality of life of humanity we must accept that it is desirable to eliminate males. Sparrow argues that the main advantages of being male derive from wrongful sexism and so, like the advantage of being white in a racist world, should be disregarded, and that female extra longevity and capacity to conceive makes up for women’s lesser weight-lifting abilities. He concludes that we must reject enhancement and favour only genetic therapy to eliminate pathological abnormalities or instead affirm enhancement and endorse the claim that humanity should be female. He rejects enhancement and argues that males have their own normality.

26Sparrow’s argument overlooks the possibility that the concern to avoid pathological abnormalities that animates therapy may also support the elimination of males, in order to minimise murder, rape, and atrocity.

27In any case, discussing male elimination is wrongheaded because there is just nothing wrong with maleness as such. In species where males and females co-parent roughly equally, dimorphism is limited and unproblematic. Parents take turns and derive many advantages from cooperation. In some species, like the pipefish, were males do the parenting work, it is large, ornamented, territorially aggressive, females that compete for the male labour. Sparrow says that dimorphism is good, but dimorphism is mainly the proportional result of polygamy and inequality in parenting. In mammalian persons, with huge maternal investment and females doing most or all the work, dimorphism is stark and there is fierce competition for females’ scarce eggs and devoted labour.

28Polygamous competition makes males larger, more aggressive, more drawn to risky behaviour and to escalating violence, more desperate to mate, more indiscriminate about mates, and less long-lived. The combination of polygamy and huge maternal investments is tragic because of the morally relevant cognitive and emotional capacities that accompany this investment, particularly in the species here discussed, and because competition intensifies with a larger price. The result is the horrific coexistence of very sophisticated and caring mammalian persons with brutal murders, rapes and infanticides. And polygamy – again produced by a shortage of certain oxytocin and vasopressin receptors which sustain pair-bonding – is to blame.

29Fortunately, we are moving away from all this. Our ancestors are believed to have been more polygamous, brutal and dimorphic than us. But then, males became more slender and graceful, more delicate and empathetic, and also more involved in raising a few offspring and less focused on thinly spreading their genes. This trend eventually gave rise to the caring, responsible, sensitive and loyal males we see today. So we are in the right path to enhancement already. We just need to figure out how we can speed this up, and further reduce dimorphism. While we learn more about how the newly discovered (Walum et al. 2008) genetic variants of the vasopressin receptors gene (alleles of the gene AVPR1a, which newspapers reported as monogamy gene RS3 334), could deliver us from evil, we can work on equal parenting, ask only the faithful to donate to sperm banks, and curse god for not having evolved us from more egalitarian and peaceful, pair-bonded apes.



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1 This is why Marc Hausers claims to have proven that tamarinds (tiny monkeys born as twins, reaching adulthood at 2 and living only 17 years) passed the Gallup test, always seemed suspicious to me.

2 The fact that length of pregnancy tends to correlate with size may contribute to explaining the pattern but does not invalidate the hypothesis.

3 Like Borat and Bruno, Ali G is a character created by Sacha Baron Cohen, a comedian not to be confused with his abovementioned cousin. The tea scene appears in the film Ali G in da House (2002).

Table des illustrations

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Paula Casal is an ICREA Research Professor at Pompeu Fabra University (Barcelona). She was previously a Reader in Moral and Political Philosophy at Reading University (2003-2011) and a Lecturer at Keele University (1996­2004). She was also a Fellow in Ethics (Harvard, 1999-2000), a Keele Junior Research Fellow (Harvard, 2000-1), a Hoover Fellow (Louvain, 2001-02), and a Leverhulme Research Fellow (Oxford, 2002-3). She is interested in social and global distributive justice, environmental taxation, multiculturalism, gender and animal ethics. Her work has appeared in such journals as Ethics, J. of Political Philos., and J. of Moral Philos.. She is an Associate Editor of Politics, Philosophy & Economics, and a founding member, and President, of the Great Ape Project-Spain.

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