Little Greek letters become weapons in war of words over trend in violence 

Two intellectual titans are arguing over whether humanity has become less violent. In his 2011 book, Steven Pinker contends that violence is way down since the stone age, or even since the Middle Ages. He looks at murder, war, capital punishment, even violence against animals.

But in a working paper released yesterday, Pasquale Cirillo and Nassim Taleb, the latter the author of The Black Swan: The Impact of the Highly Improbable, contend that Pinker has it wrong. Well, more precisely (lest I incite a riot with demagoguery) they challenge the notion that the great powers have enjoyed a distinctly long peace since World War II.

This paper launches a second round in a war of words (and equations) over the long peace. Previously, Taleb said the The “Long Peace” is a Statistical Illusion. Pinker suggested Taleb was Fooled by Belligerence.

Everything I know about the history of violence, I learned from Pinker’s TED talk. And I have not mastered the mathematical methods marshalled by Cirillo and Taleb. But I do know something about them, having written a program to do them. I think Taleb’s latest salvo mostly misses its mark. Here’s why:

  • Cirillo and Taleb invoke extreme value theory, which is designed for studying the probabilities of events such as big floods, geomagnetic storms, and world wars. Their applications of EVT models (Pareto/power law, Lomax, Generalized Pareto) dominate the paper. But these assume rather than show that the aggregate casualty rate of warfare has held steady over the centuries. EVT models can allow for time trends but the ones used here don’t.
  • Cirillo and Taleb do state and defend their assumption of no time trend. But this analysis amounts to three paragraphs on page 6. They observe that
    • Gaps between big wars are really long. E.g., after rescaling historical casualty figures in proportion to today’s world population, a war costing at least 10 million lives has hit only once a century on average (Table II). Only 70 years after World War II, they contend, it is too soon to declare that this time is different. (And here one can see how Taleb’s experience with finance bolsters his skepticism of such declarations.)
    • A simple measure of correlation over time in war deaths finds almost none. Fewer deaths in one year does not predict fewer deaths 10 or even 100 20 years later (figure 8). This cuts against the notion of trend.

    To me these facts seem relevant but inadequate to overturning Pinker’s conclusion, which synthesizes a much larger body of scholarship drawing on multiple types of evidence to document the recent, historically anomalous disappearance of violent conflict between great powers. To my knowledge there have been no ~million-death-or-greater wars between great powers since 1945. Cirillo and Taleb say globally, over 21 centuries, wars of at least that magnitude have happened every 26.71 years (again, scaling to current world population). So on the evidence presented, the long peace still looks improbable.

  • It seems to me that if Cirillo and Taleb want to rule out a time trend trend break according to their own standard of evidence, then they should introduce a post-1945 dummy in their EVT models and test whether it is statistically distinguishable from zero.

Presumably both sides would agree that among great powers, the last 70 years have been unusually peaceful. And both would agree that the future is uncertain. The rupture appears to come in the readiness to extrapolate forward from the last 70 years. Whether this rupture is great, or whether Taleb is jousting with a caricature of Pinker, I am not sure. I would find Cirillo and Taleb more compelling if they documented exactly which of Pinker’s words they find to violate the truth.

Update: further thoughts.

  • Xor

    I don’t think Cirillo and Taleb would agree that it has been “unusually” peaceful, they looked at catastrophic wars between powers and their point is that for those wars it’s well within the range of the past (I’m not aware of small wars between powers in the past).

    Although I do agree they needed to have a dummy variable for post-45, although I doubt 70 years within dozens of 130 year intervals would have made a difference.

    • David Roodman

      As far as I know, no great power has gone to war against another great power in the last 70 years. I think one cannot say the same about the 70 years before that, nor the 70 before that, etc.

      If by “doubt…would have made a difference,” you mean that a post-1945 dummy would not be statistically significant, you may be right. I still think it’s what they should check for if they want to attack the notion of a long peace. Otherwise, we’re all just engaging in conjecture.

      • Xor

        The authors might be talking across each other then: T&C are measuring very deadly wars while Pinker is measuring great power wars which might not necessarily be as deadly.

        T&C were trying to measure if we’re in temporal range of the former but I’m not sure anyone has done the same for the latter like the 70 years you mentioned.

        • Ted Seay

          >T&C are measuring very deadly wars

          …and Pinker is positing and measuring violence writ large, small, and everything in between…

          …which makes me wonder why T&C think so narrow a gauge for their own argument can in any way refute Pinker’s much broader hypothesis?

          • Xor

            Because Pinker’s claim about the “long peace” for major wars is a distinct argument in itself and accounts for much of the violence.

          • Ted Seay

            Pinker asserts that violence has diminished as Western civilization has spread, and as certain fruits of that civilization have taken broader and deeper hold. He offers as evidence reductions in ALL KINDS of violence, generally, globally and over long periods of time.

            ONE OF Pinker’s bits of evidence is John Lewis Gaddis’s “long peace” — but only one.

            Let’s say you’re right about T&C, and that they have successfully challenged Pinker on the “long peace”.

            Can you see that such a partial refutation would in no way invalidate the rest of Pinker’s argument?

            …and frankly, I’m not even willing to concede the argument to T&C on the “long peace” — war is not a statistical exercise, and even if they are narrowly correct about tail risk in this one instance, that does not mean Pinker is “wrong” in any meaningful way about the decline of violence over time…

          • Xor

            First of all, a huge portion of violence (possibility the majority) is BECAUSE of those massive wars. A hundred million people dying from the World Wars might have a tiny bit to do with overall violence levels and thus does affect the overall argument.

            Secondly, the “reduction” is only a valid argument if we’re only measuring the most recent 5% of human history. Anthropologists have shown through the fossil record that violence was virtually non-existent prior to the Malthusian crisis 13,000 years ago (which even Pinker mentions). That is, humans weren’t violent for 95% of history and still more violent than that period, despite the recent decline.

          • Ted Seay

            >First of all, a huge portion of violence (possibility the majority) is BECAUSE of those massive wars. A hundred million people dying from the World Wars might have a tiny bit to do with overall violence levels and thus does affect the overall argument.

            How can you even engage in this discussion when you clearly have not read Pinker? (At least, I hope you haven’t…)

            ‘Recently the study of war has been made more precise by the release of two quantitative datasets, which I will explain in chapter 5. They conservatively list about 40 million battle deaths during the 20th century.(“Battle deaths” refer to soldiers and civilians who were directly killed in combat.) If we consider that a bit more than 6 billion people died during the 20th century, and put aside some demographic subtleties, we may estimate that around 0.7 percent of the world’s population died in battles during that century.

            ‘Even if we tripled or quadrupled the estimate to include indirect deaths from war-caused famine and disease, it would barely narrow the gap between state and nonstate societies. What if we added the deaths from genocides, purges, and other man-made disasters? Matthew White, the atrocitologist we met in chapter 1, estimates that around 180 million deaths can be blamed on all of these human causes put together. That still amounts to only 3 percent of the deaths in the 20th century.’

            Now compare that rate to the percentage of deaths by violence in hunter-gatherer and other pre-state societies dating back to 14,000 BC:

            ‘Once researchers have tallied a raw count of violent deaths, they can convert it to a rate in either of two ways. The first is to calculate the percentage of all deaths that are caused by violence. This rate is an answer to the question, “What are the chances that a person died at the hands of another person rather than passing away of natural causes?” The graph in figure 2–2 presents this statistic for three samples of nonstate people—skeletons from prehistoric sites, hunter-gatherers, and hunter-horticulturalists—and for a variety of state societies. Let’s walk through it.

            ‘The topmost cluster shows the rate of violent death for skeletons dug out of archaeological sites.48 They are the remains of hunter-gatherers and hunter-horticulturalists from Asia, Africa, Europe, and the Americas and date from 14,000 BCE to 1770 CE, in every case well before the emergence of state societies or the first sustained contact with them. The death rates range from 0 to 60 percent, with an average of 15 percent.’

            In short, you have no argument. The rate of death from violence in ancient times lies somewhere between 5-21 times that of the 20th century (which was higher than the 21st to date).

          • Xor

            Again, we’re talking about the recent, post-45 decline in overall violence, NOT the decline relative to pre-state societies. Put differently, the discussion is on the chapter on the long peace, not the one you just quoted.

            But please, if you want to make this about all of human history, maybe you can answer why there was virtually no violence prior to ~13,000 BC which means we went 95% of human history without violence.

          • David Roodman

            Xor, how do we know that there was virtually no violence before ~13,000 BC? See 430,000-year-old skull suggests murder is an ‘ancient human behavior’.

          • Xor

            I’m talking about intra-homo sapien violence, “humans” (meaning us as homo sapiens) didn’t exist 430,000 years ago. One direct response was by Brian Ferguson who, albeit in a roundabout way, shows that no human skeletons prior to 13,000 BC had violence.
            http://www.ncas.rutgers.edu/sites/fasn/files/Pinker's%20List%20-%20Exaggerating%20Prehistoric%20War%20Mortality%20(2013).pdf

            Violence likely emerged because of the Malthusian crisis around 13,000 BC which even Pinker mentions. What he doesn’t mention is that was the origin of violence, 95% into human history.

          • Ted Seay

            >no human skeletons prior to 13,000 BC had evidence of violence.

            The scope of your ignorance is utterly breathtaking.

            http://www.pnas.org/content/102/43/15294.short

          • Xor

            It really is, from Kelley (2005):

            “The earliest conclusive archaeological evidence for attacks on settlements is a Nubian cemetery (site 117) near the present-day town of Jebel Sahaba in the Sudan dated at 12,000 –14,000 B.P. (7, 12). War originated independently in other parts of the world at dates as late as 4,000 B.P. (13).”

            We’re talking about intra-homo sapien violence, not some other hominid that predates us.

          • Ted Seay

            Is English not your first language? Is that the problem here?

            You actually claim that no human skeletons from before 13,000 BC show evidence of violence.

            Is that REALLY what you mean?

          • Xor

            The consensus of anthropologists claims this, if you want someone making this point explicitly see Ferguson:

            http://www.ncas.rutgers.edu/sites/fasn/files/Pinker's%20List%20-%20Exaggerating%20Prehistoric%20War%20Mortality%20(2013).pdf

            As of now, we have yet to find evidence of violence on homo sapien skeletons earlier than 13,000 BC. Maybe one day we’ll find a 200,000 year old mass grave but until then, that is where anthropology stands.

          • Ted Seay

            Beware consensus; there’s nothing particularly scientific about it.

            Ferguson can’t wrap his head around people choosing to fight other people. Kelly, OTOH, dates Jebel Sahaba with a 50% chance that the evidence of human-on-human violence there is older than 13,000 BC.

            (Careful distinguishing between Kelly and Keeley, BTW — “Kelley” doesn’t exist in this dispute…)

            Let’s say you’re correct, for now, that there is no evidence of human-on-human violence older than 13,000 BC, and therefore no such violence took place. Let’s just assume that here.

            So what? What is the significance in the debate between Taleb and Pinker of your contention, when the human history their discussion deals with is no more than 4,000-5,000 years old at most?

            What is the significance to THIS debate of claiming that human violence is “only” 15,000 years old?

          • Xor

            In a sense it doesn’t matter for THIS debate, because we’re talking about two separate issues:
            1). Have humans been violent for their entire history?
            2). Do great power wars no longer occur? (what I mean by “THIS” debate)

            Violence only occurring in the last 10,000-14,000 years disproves 1). and I answered it up because you kept trying to bring up the “overall” argument of decline (which is unrelated to 2).) Again this basically disproves the entirety of Pinker’s book because humans have existed for 200,000 years and thus violence is a very recent occurrence for human history overall.

            For 2). T&C show that large scale wars occur within 130 years, meaning we still have decades to wait and see whether such a war is no longer possible.

          • Ted Seay

            You are completely incoherent.

            >1). Have humans been violent for their entire history?

            Sorry, only YOU are talking about this. It has no bearing on Pinker or T&C, and therefore no place in this discussion. (And I notice your claim of no violence now only stretches to 12,000 BC, when before you had been claiming 13,000 BC — nice work, you’re moving in the wrong direction without even noticing.

            >2). Do great power wars no longer occur? (what I mean by “THIS” debate)

            Wrong again. Pinker has never made this claim, therefore T&C aren’t trying to refute it, therefore YOU KNOW NOTHING WORTH DISCUSSING HERE.

            Is it sinking in yet?

          • Xor

            We are talking about 1) because if it’s a recent occurrence then there is no “decline” to speak of (except relative to the recent emergence of violence). That’s point anthropologists like Ferguson are making. And I always put date ranges, but you know, violence not occurring for the first 93% to 95% of human history makes very little difference for the overall argument.

            Really? So Pinker’s chapter on the “long peace” isn’t claiming anything? No argument whatsoever?

          • Ted Seay

            I’m sorry, I can’t continue to argue with someone who is incapable of basic reading comprehension.

            To wit:

            You: Do great power wars no longer occur?

            Me: Pinker has never made this claim

            You: Really? So Pinker’s chapter on the “long peace” isn’t claiming anything? No argument whatsoever?

            …can you see where you might have a little, tiny problem here? Does your last statement look ANYTHING AT ALL like ANYTHING I wrote?

            Seriously.

            And I won’t even start to characterize someone who thinks anthropological timelines are of particular importance to the discussion of human violence in the 20th and 21st centuries…because, clearly, THAT is what Pinker and T&C are discussing.

            Only you care about 12,000-14,000 BC in this context.

            Really.

            No one else.

            Not one person, IN THIS CONTEXT.

            Can you not see this?

          • Xor

            Whether you respond or not, Pinker DID claim that great power wars no longer happen (or are much less likely to happen in the future), T&C aren’t attacking a straw-man it’s literally right in his chapter on the long peace.

            Right, “no one” except for the consensus of anthropologists and Pinker himself who goes all the way back to the Malthusian trap ~13,000 years ago.

            But it’s a nice technique: when I bring up that his claim on great power war is wrong just claim “but Pinker is talking about all violence!” when I bring up that Pinker is wrong on all violence just go “but Pinker is only talking about the 20 and 21st centuries!”

            You didn’t even seem to notice your constant bait and switch.

          • Ted Seay

            >it’s literally right in his chapter on the long peace.

            Quote it, word for word. Page cite and all.

            >Right, “no one” except for the consensus of anthropologists and
            Pinker himself who goes all the way back to the Malthusian trap
            ~13,000 years ago.

            This discussion is about Pinker vs. T&C.

            What are THEY debating?

            Violence in the 20th and 21st centuries. Pinker is discussing a broader
            axis of violent behaviors, which is one of the problems I have with
            T&C supposedly “rebutting” Pinker, but nobody, literally NOBODY in
            the Pinker vs. T&C debate is talking about 13,000 BC!

            Bait and switch THAT…

          • Xor

            Okay:
            Now to the money question: has the probability that a war will break out increased,
            decreased, or stayed the same over time?
            …“There is a suggestion,” he wrote, “but not a conclusive proof, that mankind has become less warlike since A.D. 1820. The best available observations show a slight decrease in the number of wars with time…. But the distinction is not great enough to show plainly among chance variations.” Written at a time when the ashes of Europe and Asia were still warm, this is a testament to a great scientist’s willingness to lets facts and reason override casual impressions and conventional wisdom.As we shall see, analyses of the frequency of war over time from other datasets point to the same conclusion.
            Pg 209-210, Chpt 5.

            And Chapter 5 is about one thing only: War. T&C are talking about one thing only: War. This isn’t rocket science, it’s a smaller, distinct argument Pinker is making about a decrease in major wars.

          • Ted Seay

            >Pinker DID claim that great power wars no longer happen (or are much less likely to happen in the future),

            You notice here that you have already toned down your claim from “don’t happen any more” to “much less likely to happen”, don’t you?

            As it turns out, Pinker claimed neither thing. The passages you quote discuss the possibility of a decline in frequency of wars*. Pinker then IMMEDIATELY adds this:

            “So does that mean mankind got more warlike or less? There is no single answer, because ‘warlike’ can refer to two different things.”

            Guess what those two things are? Frequency, as noted in the passage you cite, and magnitude. As in, “major wars” — or not. You also conveniently leave out text concerning magnitude in the passages you cite.

            Finally, and I do mean finally, since there is no convincing you that you are incorrect, even when you are forced to fabricate an argument out of conveniently edited text, there is this:

            >And Chapter 5 is about one thing only: War. T&C are talking about
            one thing only: War. This isn’t rocket science, it’s a smaller, distinct
            argument Pinker is making about a decrease in major wars.

            1) Do you honestly think T&C only wrote about Pinker’s Chapter 5? Do you believe they could claim to have refuted Pinker in toto based entirely on one chapter in his book?

            2) Pinker was not making an argument about a decrease in major wars — that’s what T&C claimed in an attempt to engage Pinker’s entire argument about human violence. They failed for the same reason you have — Pinker claimed no such thing.

            Now go read Pinker cover to cover, and come back when you’re done and capable of holding up your end of the argument…

            * Not “major wars”. Not “great power wars”. Wars.

          • Xor

            Pretty sure it’s not “toned down” if it’s literally in the same sentence. And yeah, Pinker says those two things are in fact, declining, not that they “MIGHT” be.

            1) Yes because they never claimed to have refuted everything, only the idea that major wars are decreasing.

            2). A decrease in magnitude and frequency of war isn’t also a decrease in major wars??

            Maybe before frothing at the mouth and setting up strawmen you can do well to read both Pinker and T&C.

          • Ted Seay

            I wrote: ‘You notice here that you have already toned down your claim from “don’t
            happen any more” to “much less likely to happen”, don’t you?’

            You wrote: ‘Pretty sure it’s not “toned down” if it’s literally in the same sentence.’

            Unfortunately for your argument, you originally wrote: ‘Do great power wars no longer occur? (what I mean by “THIS” debate)’

            To which I respond: You, and no one else.
            —————————————————–
            You wrote: ‘And yeah, Pinker says those two things are in fact, declining, not that they “MIGHT” be.’

            This is called an assertion. By itself, it is worthless. To be worth anything, it requires proof. The ‘proof’ you have offered so far is incorrect, false, also worthless. You will respond to this in the same manner, since your head appears utterly impenetrable.

            Have a great life. You need help.

          • Xor

            Semantics aside, Pinker is arguing for a decline something you denied. And I already showed the proof of Pinker arguing “that mankind has become less warlike since A.D. 1820. The best available observations show a slight decrease in the number of wars with time.” for both magnitude and frequency.

            The fact that you’re trying to argue out of it through semantics is just pathetic.

          • Ted Seay

            I now see the problem.

            It is absurd asking you to read an 800-page book, when, clearly, you have not read 800 total pages in your entire life.

            (And no, Spiderman does NOT count.)

            >Again, we’re talking about the recent, post-45 decline in overall violence, NOT the decline relative to pre-state societies.

            I don’t much care what you’re talking about — Pinker is discussing the whole range of human history and the record of violence contained therein.

            I will, however, note for the sake of consistency that YOU wrote THIS:

            >That is, humans weren’t violent for 95% of history and still more violent than that period, despite the recent decline.

            This statement is false. See my previous post if you’re still unsure on this point. WARNING: Reading comprehension required.

            >Put differently, the discussion is on the chapter on the long peace, not the one you just quoted.

            …this said after YOU introduce the “95% of human history” argument?

            Can you even see where you are failing here?

            >Again, we’re talking about the recent, post-45 decline in overall violence

            Look, do all of us, not least yourself, a huge favor: Go read Pinker. Then come back and tell us about his contribution to the debate on the history of human violence.

            Until you do, you will only continue to embarrass yourself — and, although you won’t believe this, I am doing YOU a favor when I say you SHOULD be embarrassed by your entire line of argumentation here.