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Matt Thornton on Violence: Why It Evolved, Why It Still Happens, and What to Do About It

The Gift of Violence: Practical Knowledge for Surviving and Thriving in a Dangerous World (book cover)

Shermer and Thornton discuss:

  • gift of violence vs. gift of fear (Gavin de Becker)
  • mission of Straight Blast Gym: “To make good people more dangerous to bad people.”
  • Why did violence evolve?
  • Are we naturally violent, pacifist, or context dependent?
  • aggression: passive, proactive, reactive, relational
  • plusses and minuses of violence
  • violence as deterrence
  • moralistic punishment and the game theory analysis of the logic of violence
  • mass public shootings and school shootings
  • gun violence in general (homicide, suicide, accidents)
  • violence against women
  • violence against children
  • male-on-male violence
  • violence and alcohol and drugs
  • violence and adultery/infidelity
  • race and violence
  • self-control and violence
  • psychopathy, sociopathy, antisocial personality disorder (APD) and violence
  • training soldiers for violence
  • choke holds and other ways to restrain someone else’s violence
  • male role models and violence
  • Rodney King, Michael Brown, George Floyd
  • police violence
  • bullying
  • fatherless homes
  • rape and sexual violence
  • self-defense
  • how to reduce violence personally.

Matt Thornton has been teaching functional martial arts for more than thirty years and holds a 5th degree black belt in Brazilian Jiu-Jitsu. His organization, Straight Blast Gym, has more than seventy locations worldwide and has produced champion MMA fighters as well as world-class self-defense and law enforcement instructors. He lives with his wife Salome and their five children in Portland, Oregon. His new book is The Gift of Violence: Practical Knowledge for Surviving and Thriving in a Dangerous World.

From Michael Shermer’s 2015 book The Moral Arc

Have you ever thought about killing someone? I have. I am not alone. In fact, the evolutionary psychologist David Buss, in his 2005 book The Murderer Next Door: Why the Mind Is Designed to Kill, reports that most people have harbored homicidal fantasies at some point in their lives. Who are these homicidal fantasists? “Not the gang members or troubled runaways one might expect to express violent rage,” Buss explained, but “intelligent, well-scrubbed, mostly middle-class kids.” The results shocked him. “Nothing had prepared me for the outpouring of murderous thoughts my students reported,” which led him to suspect “that actual homicides were just the tip of the deep psychological iceberg of murder. Could actual murder be only the most flagrant outcome of a fundamental human drive to kill?”1

To find out, Buss not only conducted his own studies, but gathered the results of other related studies, that together comprised a database of over 5,000 people worldwide. The results illuminate the darker side of human nature: 91 percent of men and 84 percent of women reported having had at least one vivid homicidal fantasy in their life. One man who acted on these fantasies, from a group of Michigan murderers whom Buss studied, said he killed his girlfriend because “I was deeply in love with her and she knew that. It infuriated me for her to be with another guy.” Jealousy is a common motive, as evidenced in another case in which a man flew into a jealous rage during sex with his wife. Why? According to him, she asked him “How does it feel to fuck me right after someone else has?” He strangled her to death in bed.2 The impetus behind jealousy is not hate, but love and attachment, as in this police confession by a 31-year-old man after stabbing his 20-year-old wife to death when she confessed to having sex with another man during a six-month separation:

I told her how can you talk about love and marriage and you been fucking this other man. I was really mad. I went to the kitchen and got the knife. I went back to our room and asked: Were you serious when you told me that? She said yes. We fought on the bed. I was stabbing her. Her grandfather came up and tried to take the knife out of my hand. I told him to go and call the cops for me. I don’t know why I killed the woman. I loved her.3

Even though most such murders are committed by men, there are enough women who do so — and with equally moralistic motives — to constitute a sizable database. For example, case #S483 in Buss’s study, a 43-year old woman, thought about killing her 47-year old boyfriend:

I had this vision of putting poison in his food. My imagination started from the moment when he is back home, and went for his bath. I would put the dinner on the table and take out 2 separate bowls for the soup. One bowl of his will contain rat poison. Without suspicion he will finish the soup. Then I visualize him suffering stomach pain, then white bubbles come out of his mouth, and the next thing he collapses.4

Case #P96, a 19-year old woman, wanted her ex-boyfriend dead after a series of events over the course of their year and a half relationship:

The things he did to make me think about killing him were as follows: try to control who I saw, what I did, where I went, when I went. He tried to control every aspect of my life once we came to college together. He would say mean things, call me names, make me feel worthless or like I couldn’t find anyone else…. There were two main events that triggered my thoughts — 1) he got in a huge fight with my mom, 2) he called me a whore.5

Buss’s point in recording the motives behind these cutthroat fantasies is to confirm the fact that most murders are moralistic in nature. In the mind of the fantasist or the perpetrator, at the time of the murder the victim deserved to die. Over the course of history there have undoubtedly been incalculable instances of abuse so violent that a violent reaction was called for; thus a case can be made that we evolved the capacity for such murderous retaliation out of self-defense. If you do nothing to defend yourself, the bully, abuser, or murderer gets away with it, thereby setting up a self-perpetuating system of brutality as a means to an end. Victims who fight back put the perpetrator (and bystanders) on notice that violence will be met with violence. For example, Buss cites the case of an Australian man named Don who was killed by his wife Sue, after 14 years of an abusive marriage:

Don had also become quite abusive, verbally and physically. The latter included many types of humiliation, and being hit across the head regularly, being threatened with death, being locked in a closet, and being forced to sit looking in a mirror while Don made derogatory comments about her. On the night of the killing, Don held a knife to Sue’s throat while threatening to kill her. He had also both locked her in a closet and urinated in her face. Later that night, after Don had gone to sleep…Sue struck him with an axe to the side of the neck about three times. She then stabbed him in the stomach about six times with a large carving knife.6

Is there anyone — aside from Don — who would not read this account with some sympathy and understanding for Sue? If someone hit me on the head, humiliated and derided me, locked me in a closet, urinated in my face, and threatened to kill me — or did this to someone I loved — I can easily imagine myself swinging that axe with my sense of moral righteousness dialed up to eleven. Moral righteousness appears to be what a woman named Susan felt when she responded aggressively to her abusive cocaine-addicted husband as he advanced on her with a hunting knife screaming “Die, bitch!” Susan kneed him in the groin and grabbed the knife — surely a rational response to a wigged-out maniac. At her trial she said, “I was terrified because he was gonna kill me. I knew the second that I stopped he was gonna get the knife back and then I was gonna be the one that would be dead.”

However, once she got started, Susan found that she couldn’t stop stabbing her husband, a phenomenon that the sociologist Randall Collins calls “confrontational tension.” This kind of exorbitant, rising psychological pressure can lead to a “tunnel of violence,” and in its most extreme expression a “forward panic” — an explosion of rage and anger that is released through aggression and violence, as in the beating of Rodney King by Los Angeles police officers who appeared on the bystander’s grainy video like a pack of wolves ripping apart their prey.7 While lost in her tunnel of forward panic violence, Susan stabbed her husband 193 times. “I stabbed him in the head and I stabbed him in the neck and I stabbed him in the chest and I stabbed him in the stomach, and I stabbed him in the leg for all the times he kicked me, and I stabbed him in the penis for all the times he made me have sex when I didn’t want to.”8

Such revenge emotions are common enough that authors and film directors count on them, as the post-rape revenge scene in the film version of The Girl with the Dragon Tattoo demonstrates. As the main character, Lisbeth Salander, tasers her rapist, ties and gags him, and tattoos “I am a sadistic pig and a rapist” on his torso in giant letters, the audience in the theater in which I saw the film cheered loudly with righteous approval.

The Evolutionary Logic of the Moral Starting Point

If you were a molecule what would you do in order to survive? First you would need to build a substrate on which to generate a replication system inside of a cell that contains machinery for energy consumption, maintenance and repair, and other features that keep the molecule intact long enough to reproduce. Once such molecular machinery is up and running the replicating molecules become immortal as long as there is energy to feed the system and an ecosystem in which these processes can take place. In time, these replicating molecules will out-survive non-replicating molecules by virtue of the very process of replication — those that don’t, die — thus the cells or bodies in which the replicators are housed are survival machines.

In modern jargon, the replicators are called genes and the survival machines are called organisms, and this little thought experiment is what Richard Dawkins means by the “selfish gene” in his book of that title. A cell, or body, or organism — a survival machine — is the gene’s way of surviving and perpetuating itself. Genes that code for proteins that build survival machines that live long enough for them to reproduce will win out over genes that do not. Genes that code for proteins and enzymes that protect its survival machine from assaults such as disease, help not just the organism to survive, but the genes as well. Survival, reproduction, flourishing: this is what survival machines do by their very nature. It is their — our — essence to strive to survive.

The problem is that survival machines scurrying around in, say, a liquid environment like an ocean or pond will bump into other survival machines, all of whom are competing for the same limited resources. “To a survival machine, another survival machine (which is not its own child or another close relative) is part of its environment, like a rock or a river or a lump of food,” says Dawkins. But there’s a difference between a survival machine and a rock. A survival machine “is inclined to hit back” if exploited. “This is because it too is a machine that holds its immortal genes in trust for the future, and it too will stop at nothing to preserve them.”

Thus, Dawkins concludes, “Natural selection favors genes that control their survival machines in such a way that they make the best use of their environment. This includes making the best use of other survival machines, both of the same and of different species.”9 Survival machines could evolve to be completely selfish and self-centered, but there is something that keeps their pure selfishness in check, and that is the fact that other survival machines are inclined “to hit back” if attacked, to retaliate if exploited, or to attempt to use or abuse other survival machines first.

Revenge and Justice as Deterrence

The emotions driving the need for justice evolved for a number of good evolutionary reasons, one of which is to deter others from free riding, cheating, stealing, bullying, and murder. A perpetrator who is cognizant of the possibility of retribution may hesitate or even fail to act altogether, assuming that he (or, less likely, she) has the normal response of apprehension and fear of the threat of punishment. And for those who lack such sensitivities to the feelings of others — also known as psychopaths — brute force may be the only currency they understand. So an evolved sense of retributive justice is natural, and in many cases it may have been the only course of action available to our ancestors. Indeed, had we not evolved such emotions our Paleolithic ancestral tribes might have been overrun by toughs, bullies, and killers, and that might have spelled the doom of our species.

How human groups developed systems of justice is the subject of anthropologist Christopher Boehm’s enlightening — and in places shocking — book Moral Origins: The Evolution of Virtue, Altruism, and Shame.10 Boehm’s analysis is derived from a database that begins with 339 pure forager societies, then subtracts out those that likely do not resemble our ancestors (mounted hunters, horticultural hunters, fur trade hunters, and sedentary-hierarchical hunters) to produce a working dataset of 50 Late-Pleistocene Appropriate (LPA) societies from which to work. These are groups either still in existence today or groups that were studied within the past century by anthropologists, and who might reasonably be assumed to represent a close approximation to how our ancestors lived. These ethnographies, in conjunction with archaeological evidence, form the basis for theories on how our species lived before the rise of civilization.11

Boehm argues that moralistic punishment evolved, in part, to solve the problem of how altruism could evolve, and how these relatively equitable societies could be stable when free riders could game the system by taking more than they put in; by, say, slacking off on a gathering expedition, hanging back during a dangerous hunt, or simply taking more than their fair share of food. Thus, Boehm found that all of these societies had sanctions to deal with deviants, free riders, and bullies, which range from social pressure and criticism to shaming, ostracism, ejection from the group, and even — in extreme cases when nothing else works — capital punishment. The sanctioning process begins with gossip as a private exchange of evaluative information about who is doing their fair share and who isn’t, who can be trusted and who cannot, who is a good and reliable member of the group, and who is a slacker, cheater, liar, or worse. Gossip permits the group to form a consensus about the deviant that can lead to a collective decision about what to do about him (and it is almost always a male). Of course the problem with hardcore bullies like psychopaths is that they don’t care about being detected and talked about, so gossip also served as a means for subordinate band members to form coalitions based on the axiom that there is strength in numbers.

It’s surprising to hear the term “capital punishment” used in the context of hunter-gatherer societies, but the death penalty is sometimes necessary to preserve group harmony in the case of an intractable thug who refuses to bend to the rules or respond to lesser sanctions. In the 50 LPA societies studied, Boehm found that 24 of them practiced capital punishment for crimes such as malicious sorcery, repeated murder, tyrannical behavior, psychotic behavior, theft, cheating, incest, adultery, premarital sex, a taboo violation that endangers everyone in the group, betraying the group to outsiders, “serious or shocking transgressions,” and unspecified deviance. The total comes to 48 percent but is probably higher because capital punishments are notoriously underreported in ethnographies since they are generally hidden from snooping anthropologists — these modern hunter-gatherer societies know that execution is prohibited by the colonial administrators in their region, so they prudently hide it from outsiders.

Anthropologists have documented many forms of disruptive behavior, which Boehm roughly separates into two categories: intimidation and deception. Intimidation includes murder, sorcery, physical violence, and bullying. Deception includes stealing, the failure to share, lying, and cheating. Of the 50 societies in the database, 100 percent reported murder, sorcery, and stealing; 90 percent said people had failed to share, 80 percent had experienced physical violence, 70 percent had bullying as a problem, 60 percent said liars were among them, and 50 percent reported cheating. All of these behaviors generated gossip in the community, which led to group decisions concerning appropriate punishments.

These traditional societies also distinguish between reversible and irreversible sanctioning of deviants. Reversible sanctions are used when the group wants to be rid of an antisocial behavior but not of the perpetrator because he is an otherwise useful member of the group. Irreversible sanctions occur in the form of either permanent expulsion (which often means death by starvation or murder by another tribe) or execution, the latter only after reversible sanctions have failed or when a bully has proven to be a serious threat to the group.

In an evolutionary context, free riders and cheaters who respond to sanctions maintain their genetic fitness and pass on their genes for modest levels of free riding and cheating, which is what we see in all societies today. Of course, as in all human traits, bullying, free riding, and cheating is the result of both genes and environment in interaction, and so we are talking about propensities and probabilities here. In a world in which modest free riding happens — often deceptively making detection difficult — we evolved cheater detection tools and the propensity to gossip about those whom we think might be trying to deceive us and cheat the system. Adding it all up, Boehm concludes that “what we have is a system of social control that can drastically reduce the genetic fitness of more driven free riders whose consciences can’t keep these dangerous traits under control, but that allows the more ‘moderate,’ would-be free riders to control themselves in matters that would otherwise bring punishment and still express their competitive tendencies in ways that are socially acceptable. It’s for this reason that free riders haven’t just gone away.”12

So an evolutionary arms race has left us with cheaters and cheating detection, free riding and free riding deterrence, bullies and bullying punishment. Out of this arms race evolved another feature of the human mind — a moral conscience — that acts as the “inner voice” of self-control. Because social sanctions allow for individuals to reform their bad behavior (before the ultimate form of punishment — banishment or execution — is employed), conscious self-awareness of one’s actions allowed for adjustments to be made of one’s behavior. “It was earlier types of social control that caused a conscience to evolve, and it’s an evolved conscience that makes individuals so adept at this important type of self-inhibition,” Boehm writes. Why, then, are there still modern hunter-gatherers being executed, banished, ostracized, and shamed by their groups for free riding? Because, says Boehm, “they hope they can get away with it.”13 In the long run, however, most don’t, but it’s a long enough run that they manage to reproduce in the meantime so their genes for such cheating and free riding have made their way to modern humans.

About the Book

In today’s modern world, we are largely isolated from the kind of savagery our ancestors faced on a daily basis. Although violence was as natural to our evolutionary development as sex and food, it has become foreign to most of us: at once demonized and glamorized, but almost always deeply misunderstood. Our hard-earned and hard-wired instincts — our evolved and trained ability to survive and overcome violent encounters — have been compromised. Yet, as even a cursory look at news headlines or a police blotter will reveal, the threat of violent crime is ever-present, and those we’ve entrusted to protect us cannot always be relied upon.

The Gift of Violence tells the story of this vulnerability and provides the average person with all the knowledge they need to reduce the likelihood of becoming a victim of violence and to increase their chances of surviving a violent encounter. Based both on the author’s decades of experience teaching everyday people how to defend themselves and on a rational approach to the scientific data, The Gift of Violence offers clear, easy-to-remember lessons for people of all ages and abilities. It is designed to empower those who’ve been affected by violence or are concerned that they or their loved ones could be. In short, it was written to help good people become more dangerous to bad people. Every reader will be armed with the necessary knowledge to harness the power of violence for him — or herself — and, in the process, to be not just smarter and stronger, but also safer.

  1. Buss, David. 2005. The Murderer Next Door: Why the Mind is Designed to Kill. New York: Penguin.
  2. Ibid., 70.
  3. Ibid.
  4. Ibid., 106.
  5. Ibid.
  6. Ibid.
  7. Collins, Randall. 2008. Violence: A Micro-Sociological Theory. Princeton University Press.
  8. Buss, 2005.
  9. Ibid., 66.
  10. Boehm, Christopher. 2012. Moral Origins: The Evolution of Virtue, Altruism, and Shame. New York: Basic Books.
  11. There are critics of this assumption — usually cultural anthropologists and sociologists who place a much stronger emphasis on the role of learning, culture, and the environment than I think is perhaps warranted by the evidence — but almost no one today denies that we have an evolved nature, and that facts about this nature may be gleaned from these numerous sources.
  12. Boehm, 2012, 201. Boehm also makes the argument for group selection — in addition to individual selection — in his book, which I think is unnecessary in making his case for the evolution of altruism and the problem of free riding and bullying. The group may seem coherent and cohesive, but it is still a group of individuals, per my discussion of the issue in Chapter 1.
  13. Ibid., 201.

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This episode was released on June 6, 2023.

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