I suggest viewing it online so that the formatting is visible.


--Mark



www.childrenofmillennium.org/heroes/lykaios3.htm


The Black Death and European Intelligence:
An Evolutionary Perspective

December 5th, 2005

There has been much recent discussion in psychological and
sociological circles on the notion that the European plagues of the
Fourteenth through Eighteenth centuries had the effect of boosting
genotypic intelligence throughout Europe in a way which precipitated
the scientific and cultural advances of the Enlightenment. While any
conclusive analysis of history is necessarily impossible due to the
obvious restrictions on data collection, this subject seems
nevertheless to be worthy of some consideration. If it is correct
that the plagues increased genotypic intelligence in Europe, then two
things must be true, the first being that intelligence is a
characteristic with substantial heritability, the second being that
the plague disproportionately affected the survival and fertility of
the less intelligent relative to their more intelligent neighbors.

That the Black Death acted as a selection event is not a
controversial idea. Many researchers believe that the increased AIDS
resistance of ethnic Europeans is directly traceable to the plague
epidemic of the Fourteenth Century.1 When one third or more of a
population dies off, there will evidently be genetic consequences of
one kind or another, and the most obvious consequence of selection by
disease is genetic resistance to disease. The high incidence of
Sickle-Cell in African populations is an example of this process at
work-a single copy of the Sickle-Cell allele grants immunity to
malaria, the endemic plague of that region of the world. So the
concept that diseases such as the Black Death can alter the allelic
frequencies in a population group is uncontroversial. The question is
whether the Black Death could have had an impact on characteristics
besides those directly related to disease resistance.

Even before considering the specific details of the spread and effect
of the Black Death, there is good reason to assume that psychological
characteristics were of substantial importance in determining which
individuals succumbed, and which survived. In the modern world,
intelligence is known to correlate positively with the following:2

height,
health,
fitness,
metabolism,
lung capacity,
infant survival,
longevity, and
facial symmetry.
These correlates demonstrate a biological link between intelligence
and vitality that should logically transcend temporal and cultural
barriers which might prevent modern psychometric analyses from being
applied to the Fourteenth century. If individuals with less innate
intelligence had reduced health and fitness compared to their peers,
then the plague should have had a more severe impact on the less
intelligent - an impact which would inevitably lead to increased
intelligence throughout the entire population.

Intelligence probably served even better as a direct preventative
than as an indirect one. Figuring out how to survive an outbreak of
plague would have presented a difficult challenge to those alive
during the Middle Ages, and while healthier and higher status
medievals likely had better odds of surviving plague, those with
foresight would have been much better at avoiding the disease
entirely. Marchione di Coppe Stefani gives a horrific account of the
events in his contemporary Florentine Chronicle, writing that "There
was such a fear that no one seemed to know what to do."3 Yet there
were many who did manage to reason out a solution of one kind or
another; consider Boccaccio's words in the Decameron:


(T)here were those who thought that to live temperately and avoid all
excess would count for much as a preservative against seizures of
this kind. Wherefore they banded together, and dissociating
themselves from all others, formed communities in houses where there
were no sick, and lived a separate and secluded life, which they
regulated with the utmost care, avoiding every kind of luxury, but
eating and drinking moderately of the most delicate viands and the
finest wines, holding converse with none but one another, lest
tidings of sickness or death should reach them, and diverting their
minds with music and such other delights as they could devise.4

Compare this with another prevalent strategy for coping with the
horrors of the Black Death:


Others, the bias of whose minds was in the opposite direction,
maintained, that to drink freely, frequent places of public resort,
and take their pleasure with song and revel, sparing to satisfy no
appetite, and to laugh and mock at no event, was the sovereign remedy
for so great an evil: and that which they affirmed they also put in
practice, so far as they were able, resorting day and night, now to
this tavern, now to that, drinking with an entire disregard of rule
or measure, and by preference making the houses of others, as it
were, their inns, if they but saw in them aught that was particularly
to their taste or liking; which they, were readily able to do,
because the owners, seeing death imminent, had become as reckless of
their property as of their lives; so that most of the houses were
open to all comers, and no distinction was observed between the
stranger who presented himself and the rightful lord.4


It is not difficult to see why the former strategy would be not only
more successful at boosting survival chances, but would have had
greater appeal for the more intelligent, as it requires an
orientation towards the future rather than towards immediate
gratification. The failure to properly integrate present and future
in human thinking is described by Jensen as being a classic
manifestation of low intelligence:


(L)ow IQ individuals have a short time horizon; that is, they are
present-oriented and more lacking in foresight than most people.
Persons with low IQ fail to adequately and realistically imagine the
future consequences of their actions. Their immediate behavior is
therefore less thoughtful and more impulsive. 2

While other personality traits (such as Extroversion), and other
cultural beliefs (such as religious fatalism or a sense of
helplessness in the face of divine retribution) probably influenced
the decision to make merry and risk death by plague, this does not by
any means point to the conclusion that intelligence had no ability to
influence the outcome of an individual's decision. Consider for
instance the example of Isaac Newton; although he wasn't alive during
the original outbreak of plague in Europe, Newton left London to
avoid a then-current outbreak of plague, and survived to ultimately
become one of the most respected men of science.

Lastly, intelligence also shows merit as a candidate for selection by
the plague because of its correlates in the social arena - possibly
the most effective way in which intelligence could affect disease
survival is through social status and wealth. In the modern era, the
correlates of intelligence also include income the following:2

socioeconomic status of origin,
achieved socioeconomic status,
voluntary migration,
functional literacy,
accident avoidance, and
freedom from alcoholism.
Many of these have with larger correlation coefficients than those
related to general health, and all would have offered protection
against plague. Whether these social variables would have been
related to intelligence during the High Middle Ages is an interesting
question which lacks a definitive answer. Yet the relationship
between intelligence and social status is likely to be robust, given
that, according to David Buss' famous cross-cultural survey,
intelligence is universally valued as an attractive characteristic in
a spouse in wealthy and developing nations alike;2 this indicates an
old selective bias favoring intelligence which should logically allow
individuals with higher intelligence to climb the social ladder no
matter what the circumstances. Knowing also that intelligence in the
modern world grants improved performance in even the most mundane of
tasks such as cooking eggs or supermarket shopping,2 it is difficult
to imagine why intelligence would have lacked utility in the High
Middle Ages. After all, omelets and town markets are hardly an
innovation of the modern world; nor is social status, which was, if
anything, of more pronounced importance throughout the High Middle
Ages.

Of course, many historians imply that the Black Death could not have
acted as a selection event, making statements such as:

Few (families) can have been spared some loss, since the plague
killed indiscriminately, striking at rich and poor alike6

And:

Filth running in open ditches in the streets, fly-blown meat and
stinking fish, contaminated and adulterated ale, polluted well water,
unspeakable privies, epidemic disease, were experienced
indiscriminately by all social classes.7

If it is true that the plague struck indiscriminately, then there
would have been no way for any character trait to have been affected
by the plague. Yet contemporary accounts belie this interpretation;
John of Fordun wrote of Scotland that "This sickness befell people
everywhere, but especially the middling and lower classes, rarely the
great."8

This should come as no real surprise. The people of Europe were
already weakened before the onset of the plague by famine, brought
about in part by high population. More people in Europe meant that
more land had to be brought under cultivation, but much of the best
land had already been parceled off. But the wealthiest individuals
would have scarcely noticed food shortages; although perhaps not so
ignorant of hardship and food scarcity as Marie Antoinette, many
noble families, and even successful trades families living in the
High Middle Ages would have had more to eat for the entirety of their
lives than the lower classes, and would have therefore been in better
physical condition to resist plague. In other words, while there was
no perfect defense against plague, being rich and powerful was quite
helpful - and having rich and powerful relatives was the next best
thing.

It is useful to have this information on class effects, since there
is no good way that contemporaries could have estimated whether the
plague struck indiscriminately within social classes or had a
disproportionate effect on the less intelligent. The best that modern
scholars can do is attempt to make conceptual arguments and show that
the research carried out on modern populations, if it were applicable
to medievals, leads to the conclusion that the plague would have had
a positive net effect on genotypic intelligence in Europe.

But does psychometric research carried out on modern populations
really have any validity when applied to social groups which lived
and died six centuries ago? This is perhaps the lynch-pin of the
evolutionary argument: the assumption that medieval society was, even
if it differed in certain aspects, broadly comparable to modern
societies. Dunnigan and Nofi provide a brief and lucid summary which
should help to address this subject:

Medieval society was different, but not so different as to be totally
alien to what we experience in the 20th century. In the 14th century,
people were born, grew up, fell in love, married, had children, and
died. People ate, got sick, took baths, dressed up for special
occasions, went to church, attended wedding receptions, gossiped, got
drunk, went to work with hangovers, committed adultery, beat their
spouses, looked after their elderly parents, grieved for their dead,
went off to war, engaged in unprotected sex as adolescents,
celebrated Christmas, went skinnydipping, kept dogs as pets, and
consulted horoscopes.9

But most important of all is this simple statement:

You can still find medieval living conditions and sensibilities in
Third World nations.9
If true, this provides the necessary link between modern research on
the one hand and medieval society on the other. If the territories of
the Middle Ages - Fourteenth Century France, Fourteenth Century
Scandinavia, Fourteenth Century Britannia, and so on - can be viewed
merely as foreign, developing countries of the modern era, then there
is really nothing to prevent any analysis of modern nations from
being applied to the Middle Ages, provided that care is taken to
account for the uncertainties of history and the inherent quirks of
the medieval era.

Fortunately, most of these quirks can be largely subsumed into
variation which exists in the modern day. For instance, one of the
most profound differences between Fourteenth Century Europe and the
modern West is the existence of a powerful religious monopoly: the
Roman Catholic Church. Following the events of the Reformation, there
has been no such monopoly in the modern West to serve as a
comparison; the character of Catholicism has mellowed significantly
in the last several centuries. Still, the Islamic world may provide a
useful parallel to the medieval Church with its fervent religious
legalism, ritualistic devotional practices, powerful hierarchy, and
militaristic theological doctrines. While the comparison is of course
not perfect, the fact that institutions similar to the old Church do
exist in the modern world prevents the medieval religious structure
from creating an insurmountable barrier to comparisons between modern
and medieval societies: a modern data set is, in theory, at least,
broad enough to account for medieval religion.

Perhaps one difference with greater importance to this discussion is
the medieval castle. Lacking well developed military technology, the
stone fortress was an unrivaled symbol of autocratic mastery. Armies
defending in castles were so difficult to defeat that the only
reliable method for taking a castle required an overwhelming
numerical advantage applied over half a year's time, or longer -
siege warfare. This allowed nobles to firmly entrench themselves
within their private fortresses and easily resist attack from all but
the most dedicated, well armed, and well supplied of enemies. And
city walls of course provided similar defense for those residing
within them. This would have given medievals a sense of continuity
and stability lacking from the modern era, where firearms have become
ubiquitous in a way which renders the castle totally obsolete. Rocket
launchers and machine guns are common even in the developing world,
preventing useful fortresses from being built on the same scale as
those of the medieval era; this probably has the effect of making
modern societies more unstable than medieval ones.

But most other differences between medieval and modern societies can
be chalked up to technological differences, educational differences,
and differences in family structure, all of which are readily
observed to exist throughout the modern era. Thus, it is reasonable
to bring up cross-cultural research in order to compare societies
which are not only separated by geographic distance, but societies
separated by temporal distance.

Gerhard Meisenberg carried out a 2004 study on the World Values
Survey which is excellent for this purpose, titled "Talent,
Character, and the Dimensions of National Culture." In the abstract,
he reports the following (emphasis added):

This study investigates the dimensions of cultural variation in the
modern world as assessed by the World Values Survey. It confirms the
previously reported existence of two major dimensions of cultural
variation that can be described as 'modern' and 'postmodern,'
respectively. Modern values are characterized by skepticism and
critical thinking, with a rejection of religion and traditional
authority along with an interest in politics. In multiple regression
models, modern values are directly related to the IQ of the
population. Postmodern values are characterized by trust, tolerance,
and self-realization. In multiple regression models, they are
inversely related to corruption. Subjective well-being is positively
related to postmodern values and negatively to modern values. Modern
values are interpreted as the emancipation of reason from the
constraints of traditional custom and religion, and postmodern values
as the emancipation of pleasure-seeking and social emotions from the
constraints of dysfunctional social systems.10

Meisenberg's description of "modern" values is highly consistent with
general descriptions of value systems flourishing during the
Renaissance. The Middle Ages were generally characterized instead by
a broad acceptance of religion, metaphorical and literary thinking,
and defense of traditional authority and custom. Of course, it would
probably be inaccurate to claim that the medieval era was the
intellectual wasteland Enlightenment thinkers often described it as
being, but by the same token it is generally accepted that the
Enlightenment was characterized more by skepticism, critical
thinking, a rejection of religion and traditional authority, and an
interest in politics, than the preceding era. That such values
correlate with the average IQ of existing populations serves as
useful evidence suggesting that something - even if not necessarily
the Black Death - boosted the average intelligence in Europe during
the centuries preceding in a way that encouraged such values to grow.

It may be tempting to dismiss this unusual argument on the grounds
that evolution can't proceed over the span of a few generations. Yet
Vining found that genotypic IQ in the 1980's was dropping, due to
differential fertility alone, at the rate of 1.6 points per
generation in a white sample, and 2.4 points per generation in a
black sample.11 Herrnstein & Murray showed that a shift of IQ 3
points produces dramatic changes in societal functioning, changing
crime rates, education rates, and poverty rates by over ten
percent.12 It is also generally reported that most creative advances
come from those with IQs above the 130 IQ mark (for instance, the
chance of earning a Nobel Prize reaches its peak at 130 IQ);13 a 6-
point shift in average IQ from 97 to 103 would change the number of
individuals above 130 IQ from 14 per thousand to 36 per thousand,
roughly doubling the creative potential of a society undergoing such
a shift.

Remember, all that is necessary for natural selection to act on a
trait is for that trait to carry substantial heritability; in the
modern era, the heritability for measured IQ is approximately 75%, as
reported by the American Psychological Association.14 Could this
heritability have been lower during the Middle Ages? Indeed, it
probably was. Poor nutrition and widespread teratogens (such as
alcohol, which was consumed ubiquitously by medievals, even pregnant
mothers) would have added environmental variation to intelligence
differences existing within the population. This would not, however,
have eliminated the genetic contribution to intelligence, merely
watered it down. Even a more modest heritability of 60% or even 40%
would have been easily enough to allow for selective forces to act on
intelligence through a few hundred years of pestilence and plague.

As a final check on the utility of this model, it is useful to
compare the areas in Europe which were hit hardest with those that
suffered less overall from plague deaths. Because genetic diffusion
has taken place over the many generations since the primary selection
event represented by the onset of the Black Death in the middle of
the Fourteenth Century, the end of the plague in Europe during the
Eighteenth Century, and the start of the Twenty First Century, it
will not be possible to consider smaller areas and sub-populations,
but the hypothesis should still be testable at the larger scale.
According to Wikipedia, the Black Death struck Eastern Europe less
hard than Western Europe because of lower population density towards
the East;15 thus, the evolutionary model predicts higher overall
intelligence for Western than Eastern Europe. Does the data bear this
out? According to IQ studies compiled by Richard Lynn and Tatu
Vanhanen, Eastern Europe is significantly lower in average IQ than
Western Europe; here are the IQ figures themselves (all given
relative to a British mean of 100):16

102 IQ:
101 IQ:
100 IQ:
99 IQ:
98 IQ:
97 IQ:
96 IQ:
95 IQ:
94 IQ:
93 IQ:
92 IQ:
Austria, Germany, Italy, Netherlands
Sweden, Switzerland
Belgium, United Kingdom
Hungary, Poland
Denmark, France, Norway
Czech Republic, Finland, Spain
Russia
Portugal, Slovenia
Romania
Bulgaria, Ireland
Greece



Despite a few outliers (namely, Portugal and Ireland), and further
despite some inescapable margin for error resulting from problems in
data collection and test design, it is apparent that the Western
European nations do indeed have higher overall averages than the
Eastern European nations in measured IQ, just as predicted.

Thus, the evolutionary argument can be considered complete: the trait
in question not only shows good heritability and apparent sensitivity
to selection by plague, but this model generates testable hypotheses
which are upheld by the available data. In a sense, then, what
medievals perceived as an act of divine retribution for their
sinfulness was instead a whetstone which honed their minds in such a
way as to allow for the scientific explosion modern historians
describe as "The Enlightenment."

But the outliers in the above table are worth further consideration.
Portugal has a substantial African element in its gene pool, as does
Greece, and it is therefore unsurprising to see these two countries
scoring low in IQ. But Ireland is more of a puzzle. Why would modern
Ireland score fully 7 IQ points below neighboring Great Britain? One
common answer, casually offerred by Matt Nuenke is that Ireland, too,
underwent a recent selection event after the Black Death: the potato
famine.17 Roughly a third of the Irish migrated from Ireland, leaving
half of the remainder to starve. Voluntary migration is correlated
with IQ, probably for many reasons touched on above such as foresight
or sufficient wealth for travelling abroad; the more intelligent left
Ireland and experienced with higher survival rates than the less
intelligent.

This is arguably what was observed in the recent New Orleans
disaster, where it was primarily the poorest and most strongly Black
element of the population that remained behind to suffer the brunt of
hurricane Katrina. It is especially interesting to note that New
Orleans has a large Creole population which, despite being socially
identified as "Black," was notably absent in disaster footage,
indicating that they generally fled the area alongside the ethnic
Europeans. Given that the heritability of racial IQ differences is
somewhere on the order of 50%,2 this is compelling evidence that the
selective model presented in this paper is in effect during many
different kinds of disasters, not only disease epidemics. It seems
especially effective with disease, however, given the extremely high
rates of HIV and AIDS in contemportary Black and Latino populations
relative to those of more intelligent racial groups.

One question this analysis cannot answer is "Why didn't East Asia
experience a Renaissance if Europe did?" East Asia also experienced
plague deaths, possibly more than Europe did, and shows a
significantly higher average IQ. This presents a problem for any
explanation on the European Renaissance which relies entirely on
disease and intelligence, and points out a weakness in the model, and
the necessity of bringing other explanations to bear. It is worth
pointing out that historians have never needed evolutionary or
psychometric models to explain the changing value systems of the
Enlightenment period; there have always been reasonable military,
political, religious, social, and economic explanations available.
Some probable environmental causes for the rise of the European
Enlightenment include:

Weapons technology, such as gunpowder and the crossbow which together
undermined the authority of the aristocracy by outmoding its knights,
and cannons, which greatly lessened the societal stability created by
castles,
The rise of the cities, which further weakened the power of the
aristocracy by developing the economic power to rival and ultimately
surpass that of most nobles;
Increasing education and literacy of the peasant classes;
Increasing anticlericalist sentiments germinated around the
Fourteenth century which weakened Church authority; and also
The plague itself, which destabilized the social system and created a
labor shortage which increased the economic power of skilled
tradesmen.

Disputing the salience of these points would be counterproductive,
since they all offer useful explanations for the events of the
Renaissance. But many of these can only offer a speculative
explanation for the lack of any obvious East Asian Renaissance, and
all of them lack the benefit of a century of psychometric and
sociological research, which the evolutionary explanation has behind
it. Consider for example anticlericalism, which, although a
reasonable explanation for the eventual Reformation with the added
appeal of being restricted to Europe and not Asia, is nevertheless
missing a scientific basis. There is also the further question of the
timing of the Reformation, which is imperfectly consistent with
anticlericalism as an explanation-opposition to the Church would have
been strongest around the time of the onset of the Black Death, so
why did the heresy of Wycliffe fail to take root when Martin Luther's
Reformation succeeded? Of course, this is precisely what the
evolutionary model would predict, since the early anticlericalism
would have arisen before intelligence had risen sufficiently to
encourage organized political action against oppressive religious
regimes; the plagues continued to wash over the European populace for
many centuries following the initial outbreak. The best use of the
analysis detailed in this paper, then, is to apply it as a supplement
to more traditional models rather than as a single overarching
explanation for the Enlightenment in Europe.

Although the conclusions drawn in this paper are obviously tentative,
they suggest a few interesting consequences for human society in the
future. Perhaps some disaster, affecting billions of human beings
over several generations, could someday raise intelligence to
Enlightenment levels and beyond. Perhaps an effective eugenics
program which raised the average intelligence by fewer than ten
points could spur a new Renaissance in the populace which dared to
apply it on itself. But most intriguingly, it appears that the
consequences of rising intelligence are an increase in
secularization, a rejection of traditional authority, and heightened
political participation. This appears true on both an individual and
national scale, given not only Meisenburg's analysis above, but the
evidence that IQ relates on an individual level to liberalism,13 to a
rejection of traditional religion13, and to the personal decision to
vote in democratic elections,12. This being the case, it appears that
the survival of traditional religious and governmental forms such as
monotheism and a centralized monarchy would be jeopardized by the
application of global-wide eugenics. Or, stated another way, perhaps
the only hope of substantially increasing human intelligence through
eugenic means resides in the adoption of modern religious and
governmental forms which anticipate the higher intelligence of future
human beings.



References


1. Trinkl, Alice. "A Relative Of Smallpox Is First Virus Found To
Invade Cells As Hiv Does." December 2, 1999.


2. Jensen, Arthur. The g Factor: The Science of Mental Ability.
(1998)


3. Stefani, Marchione di Coppo. Cronaca Fiorentina. Rerum Italicarum
Scriptores, Vol. 30. , ed. Niccolo Rodolico. Citta di Castello: 1903-
1913


4. Boccaccio, Giovanni. The Decameron. M. Rigg, trans. Vol. 1, pp. 5-
11. London: David Campbell. (1921)


5. ABC Radio National Science Program. "Descent of Man: Stone Age
Minds in Modern Skulls." (2000)


6. Bolton, ed. Ormrod and Lindley. The World Upside Down: Black Death
in England. (1996)


7. Holt and Rosser, The English Medieval Town. (1990)


8. John of Fordun, Scotichronicon. (1384)


9. Dunnigan, James F. and Nofi, Albert A. "Medieval Life and the
Hundred Years War." Hundred Years War Archives. (1997)


10. Meisenburg, Gerhard "Talent, Character, and the Dimensions of
National Culture." Mankind Quarterly. (2004)


11. Vining, D. R. "On the possibility of the re-emergence of a
dysgenic trend with respect to intelligence in American fertility
differentials." Intelligence, 6, 241-264. (1982) 12. Herrnstein,
Richard and Murray, Charles. The Bell Courve: Intelligence and Class
Structure in American life Free Press (1994) 13. Henshaw, Mark W.
These Hidden Truths: Psychometrics, Society, and the Unspeakable
Heresies of Our Time Iuniverse (2005) 14. Neisser, Ulric. et
al. "Intelligence: Knowns and Unknowns." Washington, DC: American
Psychological Association. (1996)


15. Wikipedia: The Online Encyclopedia.


16. Lynn, Richard and Tatu, Vanhanen. IQ and the Wealth of Nations.
(2002)

17. Nuenke, Matt. "A Review of The Book Eugenics: A Reassessment by
Richard Lynn."