Because most philosophies that frown on reproduction don't survive.

Friday, December 16, 2011

Pinker's Bogus Statistics in Better Angels of Our Nature

I have yet to read Steven Pinker's Better Angels of Our Nature, though I've read one or two of his articles expounding it's central thesis: that over time humans have become less violent.

I'd tend to think that the basic thesis is probably true, at least to the extent that we consider this as personal, physical violence. Humanity has become more affluent over the centuries, and in general more affluent people are engage in personal violence less. Further (and this Pinker does not seem to take into account) European/Western culture has become increasingly dominant the world over, and that brings with it a bit of vestigial Christianity and Christianity's opposition to revenge and needless violence.

However, while Pinker's central point seems to have some amount of validity, he seems to have engaged in a fair amount of "too good to check" acceptance of very shoddy figures in support of his thesis. Humphrey Clarke of Quodlibeta has been doing a very good series of posts digging into the bogus statistics, odd assumptions, and misrepresentations that crept into Pinker's work. His most recent highlights some particularly egregious claims. For instance:

The three founders of Protestantism, Luther, Calvin, and Henry VIII, had thousands of heretics were burned at the stake, as they and their followers took Jesus literally when he said, “If a man abide not in me, he is cast forth as a branch, and is withered; and men gather them, and cast them into the fire, and they are burned.”

Protestants certainly killed their share of heretics over the years, but as Humphrey points out, the three individuals that Pinker accuses can't really be accused of killing "thousands". More like "about a hundred". That distortion, however, is nothing compared to the next:

Christian conquistadors massacred and enslaved native Americans in vast numbers, and perhaps twenty million were killed in all (not counting unintentional epidemics) by the European settlement of the Americas.

However, not only is it hard to come up with any rational way of arriving at this number after you exclude diseases, but Pinker apparently arrived at this number simply by averaging some estimates provided on the Necrometrics.com website -- estimates which the author of the page states to be unreliable guesses on the part of the authors of the studies involved.

This may not undercut Pinker's basic thesis, but it does certainly call into question whether he had any business writing a book (rather than a brief essay or two) if his research was going to be so sketchy in places.

17 comments:

Andy said...

I may be showing my ignorance here, but the only burning I'm aware of involving either Calvin or Luther was the execution of Servetus, an execution in which Calvin requested a beheading instead of burning at the stake. I have no doubt Henry VIII had people burned for heresy, but have often seen these allegations of the number of Christian-related executions ridiculously inflated. (eg - fun exercise, ask the average militant atheist how many people were executed during the 350+ year long Spanish Inquisition, don't be surprised if the number with which they return exceeds the deaths from the Holocaust).

Darwin said...

According to Humphrey, you're quite correct. I didn't quote him in detail, but he answers the accusation against Calvin, Luther and Henry VIII with:

Henry VIII burned 81 heretics, Calvin burned 1 (Servetus) and Luther believed that burning heretics was against the will of the Holy Spirit, thus giving the softie a fat 0. Not a very impressive total for the 3 founders of Protestantism.

I summarized that as "about a hundred", but to be fair to Luther and Calvin, it's basically just good old Henry doing all the toasting.

MacBeth Derham said...

So much of Pinker's linguistics "work" is just Chomsky-worship. He is sure to have gleaned this unhistorical mess from someone else, too.

Mariana said...

Pinker's linguistics work is of equally shoddy quality. In an undergrad-level linguistics course, I had good fun writing a scathing paper about his egregiously bad research.

He just gets published because he's associated with Harvard.

Anonymous said...

"perhaps twenty million were killed... by the European settlement of the Americas."

Ah, does anyone get to state blatant untruths in publicly published work, so long as one precedes every howler with "perhaps?"

All but a handful of the Amerinds in North America were warlike neolithic hunter-gatherer cannibals who did not practice agriculture. It seems very implausible that there were ever more than one million of them alive at any given time, from the Arctic Circle down to the Isthmus of Panama, as hunter-gatherer methods, even supplemented with cannibalism, could not have produced sufficient food for more.

And yes, the truth does matter, the preposterous agitprop does matter.

Darwin said...

Anon,

It is correct to describe all Native Americans prior to European contact as neolithic, as smelting had not been mastered anywhere on the continents, but agriculture was widespread in significant areas of South, Central and even North America. They were most certainly not universally hunter gatherers.

North America was certainly much less densely populated than Central and South America, but all recent estimates that I've seen put the population of the two continents (which, after all, included the sizeable and agricultural Aztec empire) at 20 million or more. The problem with Pinker's claims is that violence was overwhelming not the massive die-off of native peoples -- disease was. Given that diseases to which the indigenous population had no immunities wiped out 50-90% of the native populations -- there were most certainly not 20 million available for Europeans to kill, even if they had had the logistical ability and desire to do so (which they didn't.)

Foxfier said...

Darwin, have you heard the new-ish claims that the American Indians were fairly advanced, but had a 90-95% die off so that by the time anyone recorded anything about those who didn't live on the coast, they were basically in a post-apocalyptic state?

(I can't think of anything that would actually kill off more than 50% of two entire continents, especially when human propulsion is the only option.....)

Darwin said...

Foxfier,

Yeah, I gather there's pretty good evidence at this point that after the "first contact" in Central America, pandemics of European diseases were often spreading among Indian populations faster than Europeans actually were. Thus, for instance, when the Pilgrims arrived in Massachusetts, the local Indian population had already plummeted something like 70-90% over the last 20 years due to waves of small pox and other diseases that were common in Europe but to which Native Americans had no immunity.

We've seldom seen plagues like that elsewhere in history in part because diseases don't tend to totally come out of nowhere, already well adapted to attacking the human body. In this case, diseases had already had thousands of years to get really good at inhabiting the human body, and then got a chance to attack a population with no immunities at all.

Foxfier said...

Darwin-
every time I ask someone to tell me the support for it, they offer articles on things like a group of three villages totaling less than a 100 people who someone's grandma remembered being there one year and the next there wasn't anyone left so they assume that everyone died, or they extrapolate the death rate on an island that was fighting with the Spanish, being slave labor and had the diseases. Then there's the whole disease vector problem, when land animal populations from one state to the next won't interact that much....

Heck, I can't even get anyone to show me an animal variation of it! A claim that big should have some really dang good background to it, both theory and physical evidence based. (Head-banger: the one guy I've heard defend it on the radio argued that there was no physical evidence because they didn't make physical evidence. It was Coast to Coast, but wow.)

If there was enough interaction to spread the diseases that much, the American Indians should've had a similar trove of diseases that would spread like wildfire for the Europeans-- probably with a higher survival rate, since there was some medicine, but more than the only answer I'm offered of syphilis. (I know, I know, THAT is a big argument point, too!)

Darwin said...

Foxfier,

It's not something I've read a whole lot about. One particular example that I recall reading about involves Squanto of Thanksgiving fame. The guy apparently had quite the exciting live, having been taken to Spain by earlier settlers to be sold as a slave, freed by friars there, worked in England for a while, and made it back to the Plymouth area, only to find that the area had been decimated by disease while he was gone. Wikipedia covers it a bit:

http://en.wikipedia.org/wiki/Squanto

Looking around a little, I see this article on early settlers in the Washington State area running into Indians who had visibly had small pox, and hearing about an epidemic which had killed a lot of the populations nearby:

http://www.historylink.org/index.cfm?DisplayPage=output.cfm&File_Id=5100

I know some of the early Spanish missionaries documented epidemics among the natives, though I don't know when it became clear to Europeans that the Indians hadn't had these diseases around in the first place the way Europeans had.

I also ran into this paper on paleoepidemiology (haven't read it all, just the beginning) which talks about the difficulties in modeling this kind of thing:

http://www.as.ua.edu/ant/bindon/ant570/Papers/NewWorldPaleoepidemiology.pdf

Plus this article on HistoryLink which talks a bit about evidence:

http://www.earlyamerica.com/review/2007_summer_fall/native-americans-smallpox.html

In the areas where I know a bit more about archeology (Greece and Rome) we look for both written records of catastrophy and for signs of city depopulation and breakdown. Although I gather there are a number of reports from early explorers of abandoned villages, clearly this kind of evidence is going to be a lot sketchier for native populations which tended to live in small villages without using much stone in building and didn't leave behind any writing.

As for why things didn't go the other way: Most of what I've read has attributed this to the fact that Europeans, living in cities and in close contact with domesticated animals, were a lot more susceptible to disease than the Native Americans, who tended to live in small concentrations and didn't have domesticated animals.

Going back in history, some major plagues (including the Black Plague) seem to have come to Europe from the equally urban and animal domesticating areas of China and India. So it's not so much that Europe was never hit by foreign diseases, but that the Native Americans didn't have as much to pass back the other way.

Of course, if it's correct that syphilis is from the Americas (which most things I've read say) it managed to get around quite a bit. Columbus reached American was Henry VIII of England was a year old, and it managed to get to him within 40 years or so from that time. (Though I don't know if that says more about the spread of syphilis or Henry VIII's habits...)

Foxfier said...

See, that's what I mean-- the source for the wiki mention mentions that Squanto's tribe was decimated, and that estimates went from a third to 90, highly influenced by assumptions folks make on what the prior population was. As far as I can tell from articles like this (sorry, it's the only one I could find that actually gave the source for the estimates-- no idea how they're figuring the carrying capacity of the area, since most of these high claims also assume that the prior culture was more advanced) a lot of the estimates depend on sources like "a trapper went through and said there were nine empty tents and some bodies" or "the guy who bought skins from the native trappers told his bosses that they were almost entirely wiped out."
Amusingly, one of the quotes in the article I linked mentions that they found out about some of the illnesses because people abandoned their village and refused to go near when people started dying. Makes sense to me on an emotional level, but would also make for a lot of abandoned villages, complete with the corpses of those who didn't run off.

I don't doubt that disease hit hard, I just doubt a nation-wide 90%+ population decline on wobbly evidence. Either they'd have a population that promoted the spread of disease the same as Europe's and there'd be some coming back, or they had a population that didn't spread diseases very well and you'd have a bunch of small, dire epidemics. (Which would fit the solid evidence just as well.)

The article on Washington Indians mentions that the diseases showed up when the locals got involved with Europeans.
It also made a head-banger mistake in assuming "Native American population" wasn't highly influenced by political aspects-- I've got an ancestress who would've disappeared from the count of Indians because she married a pastor and assimilated; these days, there's no cost to being an Indian and you can get something out of it, so the population is exploding.
I can't say I've ever heard of salmon getting small pox, either....

mary said...

Darwin and Foxfier,
You would both like to read Guns Germs and Steel by Jared Diamond about this very topic. Foxfier thinks the Native Americans would have had a trove of communicable diseases at the ready to transmit to the Europeans, but Native Americans did not domesticate large animals the same way the Europeans had for millennia, and there is something about this co-evolution that creates highly-communicable and deadly diseases like small pox and the like.

Foxfier said...

Mary-
not quite.
Either they'd have a population that promoted the spread of disease the same as Europe's and there'd be some coming back, or they had a population that didn't spread diseases very well and you'd have a bunch of small, dire epidemics.

Darwin said...

I sort of let this one slip, so several responses:

Foxfier,

I don't doubt that disease hit hard, I just doubt a nation-wide 90%+ population decline on wobbly evidence.

I wouldn't take the 90% estimate as anywhere all that solid. As you point out, there aren't good numbers available in a number of circumstances, and necessarily any means of estimating how big a population was from what it left behind is hard when we don't have a chance to look at what a normal, non-decimated population looks like, see how much it leaves behind, and tie that to a known population.

There are similar problems with estimating Western plagues such as the Black Death (for which you'll hear estimates that anywhere form 20% to 60% of Europeans died in the big initial plague) and various classical catastrophies such as the "Dark Age" that fell between the Mycenaean period and the rise of Classical Greek culture, the Great Plague of Athens during the Peloponnesian war, etc. Heck, even in the 20th century the estimates of how many people died because of the Ukrainian famine that Stalin caused vary by a factor of 2x (it doesn't help that Stalin had his own census people executed for producing results he didn't like.)

All of which is to say, I don't think it's surprising that it's hard to say whether the decimation of Native Americans by European diseases was 90% or 70% or 50% -- though it does appear to have been somewhere in that range and my understanding is that people tend towards the higher end of that set of estimates.

Darwin said...

Mary,

You would both like to read Guns Germs and Steel by Jared Diamond about this very topic.

Actually, I did read Guns, Germs and Steel a couple years ago along with Diamond's Collapse. I thought they were mostly good popular reading, though Diamond tend to get carried away with hints that seem to fit with his pet ideas and appears to have got a couple of things wholly wrong (for instance, recent research into Easter Island suggests his theories there were pretty far off.)

Darwin said...

Foxfier,

Either they'd have a population that promoted the spread of disease the same as Europe's and there'd be some coming back, or they had a population that didn't spread diseases very well and you'd have a bunch of small, dire epidemics.

I think you might be mixing two issues here:
1) The cultural and technological characteristics of the a civilization[s] and the extent to which they facilitate the spread of disease, and
2) The prevalence of specific diseases and their related immunities in a given population's gene pool.

1) is going to have a lot to do with sanitation, population density, travel, etc. If people travel all over the place, its easier for them to spread a disease than if people never tend to leave the 20 mile radius around where they were born. If they dump their sewage in the same river they drink from, it's easy for diseases to spread via drinking water. And if they live in dense cities with poor sanitation, all the more so because no you can add huge amounts of human contact, pests, etc. to the problems springing from the sanitation issues.

In relation to 1), the Europeans had a civilization much more efficient at spreading disease than the various Native American civilizations did circa 1500. Not just because they had a much more urban civilization with lots of travel, but also because of the sheer population density. According to the highest estimates, the total population of North and South America may have been nearly that of Europe in 1450 (more likely it was half or less), but the difference is that Europe is much, much smaller than the Americas.

However, this actually set up the Native Americans to get clobbered by 2). The fact that European civilization was comparatively good at transmitting disease and that their domestication of large mammals had allowed for more diseases to be in circulation due to diseases jumping back and forth between human and animal populations (with lots of opportunity for mutation and adaptation given the more diverse set of host creatures -- though also the occasional lucky coincidence such as the tendency of cow pox to cause immunity to the much deadlier to humans small pox) Europeans as a genetic group had much greater resistance to disease (and to the diseases common in Europe in particular) than the Native Americans did. They also just had more diseases -- again due to the factors in 1), and perhaps a bit of "luck" as well. As a result, although the Native populations weren't particularly good at spreading disease (and it took much longer for European diseases to roll across the Americas than it did for the Black Death to roll across Europe 150 years earlier) the results when disease did spread (whether through the native population itself or just as Europeans started to show up) it tended to be pretty catastrophic.

Foxfier said...

I think we got cross-points somehow... it looks like we agree, the Indians simply were not as efficient at spreading disease.

I was objecting to the claim that not only were they amazing effective at it, the population average death-rate was also higher than most of the observed epidemics. (even figuring that deaths from starvation and lack of nursing might be higher...oy)