Is sociopathy an illness? We often think so … to the point that the word “sick” has taken on a strange secondary meaning. If we call a ruthless, self-seeking person “sick,” we mean he should be shunned at all costs. We don’t mean he should take an aspirin and get some rest.

Sociopathy doesn’t look like a mental illness, being much less incapacitating than schizophrenia and most mental disorders. A sociopath can deal with other people well enough, perhaps too well. As Harpending and Sobus (2015) point out:

It is a psychopathology because of what sociopaths do to us, and it has significant legal, political, and moral consequences for all of us. Most criminals are probably sociopaths according to some definition (the figure of 80% is often quoted).

Sociopaths regularly present the following characteristics:

onset before age 15, childhood hyperactivity, truancy, delinquency, disruption in school

early and often aggressive sexual activity, marital histories of desertion, non-support, abandonment

persistent lying, cheating, irresponsibility without visible shame

sudden changes of plan, impulsiveness, unpredictability

charm and a façade of sensitivity

high mobility, vagrancy, use of aliases

Sociopaths follow a life strategy that is adaptive for themselves but ruinous for society. Harpending and Sobus (2015) argue that they succeed so well because they know how to manipulate social relationships to their advantage.

Sociopathy is at least moderately heritable (Hicks et al., 2004). Interestingly, it seems to cluster with hysteria in first-degree relatives, with sociopathy being expressed in the males and hysteria in the females. Harpending and Sobus (2015) argue that “hysteria is the expression in females of the same genetic material that leads to sociopathy in males.” In short, “sociopathy in females is the result of a greater dose of the genetic material that leads, in smaller doses, to hysteria, namely, hysteria is mild sociopathy.”

If sociopathy is adaptive, why does it affect only a minority of us? It seems that the rest of us have developed counter-strategies of looking for signs of sociopathy and expelling suspects from society … and the gene pool. This is probably why sociopaths tend to be always on the move—if they stay too long with the same people, they risk being detected and dealt with.

Gene-culture coevolution

We adapt to our cultural environment as we do to our natural environment. More so in fact. The last 10,000 years have seen far more genetic change in our ancestors than the previous 100,000, this speeding up of evolution being driven by the entry of humans into an increasingly diverse range of cultural environments.

Sociopathy may thus propagate itself more easily in some cultures than in others, with the result that its incidence may likewise differ from one to another. In a small band of hunter-gatherers, a sociopath will not last long because he is always interacting with the same small group of people:

In a 1976 study anthropologist Jane M. Murphy, then at Harvard University found that an isolated group of Yupik-speaking Inuits near the Bering Strait had a term (kunlangeta) they used to describe “a man who … repeatedly lies and cheats and steals things and … takes sexual advantage of many women—someone who does not pay attention to reprimands and who is always being brought to the elders for punishment.” When Murphy asked an Inuit what the group would typically do with a kunlangeta, he replied, “Somebody would have pushed him off the ice when nobody else was looking.”(Lilienfeld and Arkowitz, 2007)

In a larger community, a sociopath may evade detection long enough to reproduce successfully and pass on his mental traits. Finally, in some cultures he can use his manipulative skills to dominate the community, becoming a “big man” and enjoying very good opportunities for reproduction.

This Pandora’s Box was opened when humans gave up hunting and gathering and became farmers. First, farming supported a much larger population, so it became easier for sociopaths to move about from one group of unsuspecting people to another. Second, farming created a food surplus that powerful individuals could use to support underlings of various sorts: servants, soldiers, scribes, etc. There was thus a growing class of people who did not directly support themselves and whose existence depended on their ability to manipulate others.

Finally, in the tropical zone, farming greatly increased female reproductive autonomy. Through year-round farming, women could provide for themselves and their children with less male assistance. Men accordingly shifted their reproductive strategy from monogamy to polygyny, i.e., from providing for a wife and children to inseminating as many women as possible. This kind of cultural environment selected for male seducers and manipulators rather than male providers. Conversely, it selected for women who feel only an intermittent need for male companionship and who from time to time are able to coax assistance from people who are not so inclined:

Ethnographic descriptions of women who live in social contexts of low male parental investment portray women who are very demanding. Young women demand help from kin on behalf of children. When the help is not forthcoming the mothers often summarily dump or deposit the child or children at the door of a relative who (in their judgment) will not turn the children away. Women demand gifts from boyfriends for themselves.(Harpending and Draper, 1988)

In women, this selection pressure favors a condition known medically as Briquet’s syndrome and more commonly as “hysteria”:

When males are not good risks for parental investment, females will adjust their behavior accordingly. A common clinical characterization of Briquet’s syndrome is a woman who exaggerates need, who demands high levels of attention and investment, who deceives herself and others as to her requirements. The strategy (learned or inherited) makes sense for a woman with high exposure to low investment males. These males, however, are so fickle and so mobile that they can be dunned only in the short run.(Harpending and Draper, 1988)

Sociopathic behavior, be it hysteria or full-blown sociopathy, is not favored in hunter-gatherers, since both sexes invest heavily in their offspring and in each other. The selection is for men and women who can bond strongly with one partner:

[…] abandonment of the pair bond by either partner is likely to be deadly for the offspring. Draper (manuscript) finds that men with more children spend more time hunting than men with fewer dependents; that is to say that more offspring are directly translated into more parental work for the male. Pennington and Harpending (manuscript) found that infant mortality among women who had more than one mate during their reproductive careers was nearly twice as great as infant mortality of women who had only one husband. […] In societies of this type the contexts for the anti-social trait are unfavorable. There will be no pay-offs for anti-social behavior and the bearer of the trait will be readily detected and ostracized. (Harpending and Draper, 1988)

Strategy and counter-strategy

Sociopathy is therefore not an illness but a strategy. It has been least successful in small societies where both sexes invest heavily in care for their partners and offspring. It has been more successful in larger societies, particularly those where men invest less in partners and offspring. Indeed, because sociopathy does so well in such contexts, it may have hindered the development of larger and more complex societies.

In most large societies, people seek out and expel sociopaths from their local kin group and treat everyone else with suspicion. The result is the “amoral familialism” we see throughout much of the world. People prefer to deal with relatives, hire only relatives for their businesses and, as a rule, act morally only towards relatives. Thus, the high-trust environment of the family cannot extend to society in general. Among other things, this is why the market economy has failed to develop spontaneously over most of the world and over most of history. Without strong-armed government intervention (military pacification, police, courts, etc.), markets remain marketplaces—places of exchange that are highly localized in space and time. The market principle cannot spread to most economic transactions.

Some humans have resolved this problem by freeing themselves from the straitjacket of kinship, by adhering to social rules that apply to everyone, and by ruthlessly expelling rule breakers wherever they may be. This is the adaptation that Europeans have developed to the north and west of the Hajnal line. The relative weakness of kinship ties and, correspondingly, the relative strength of individualism favored a complex of psychological traits that may be summarized as follows:

– capacity to internalize punishment for disobedience of social rules (guilt proneness).

– capacity to simulate and then transfer to oneself the emotional states of other people, especially when such people are affected by rule-breaking either by oneself or by others (affective empathy).

– tendency to frame moral rules in universal, absolute terms, i.e., moral universalism and moral absolutism, as opposed to situational morality based on kinship. Rule-breakers are likewise condemned in absolute terms and may be expelled from the entire community, as opposed to being ostracized by close kin.

The above mental package brought Northwest Europeans closer than other humans to the threshold where one could escape the limitations of kinship and organize society along other lines, notably the market economy, the modern State, and political ideology. It thus became possible to meet the challenge of creating larger societies while ensuring compliance with social rules and a high degree of personal autonomy.