Charles Murray
Commentary Magazine
Since its first issue in 1945,
COMMENTARY has published hundreds of articles about Jews and Judaism. As
one would expect, they cover just about every important aspect of the
topic. But there is a lacuna, and not one involving some obscure bit of
Judaica. COMMENTARY has never published a systematic discussion of one
of the most obvious topics of all: the extravagant overrepresentation of
Jews, relative to their numbers, in the top ranks of the arts,
sciences, law, medicine, finance, entrepreneurship, and the media.
I have personal experience with the
reluctance of Jews to talk about Jewish accomplishment—my co-author, the
late Richard Herrnstein, gently resisted the paragraphs on Jewish IQ
that I insisted on putting in The Bell Curve (1994). Both history and
the contemporary revival of anti-Semitism in Europe make it easy to
understand the reasons for that reluctance. But Jewish accomplishment
constitutes a fascinating and important story. Recent scholarship is
expanding our understanding of its origins.
And so this Scots-Irish Gentile from
Iowa hereby undertakes to tell the story. I cover three topics: the
timing and nature of Jewish accomplishment, focusing on the arts and
sciences; elevated Jewish IQ as an explanation for that accomplishment;
and current theories about how the Jews acquired their elevated IQ.
_____________
From 800 B.C.E. through the first
millennium of the Common Era, we have just two examples of great Jewish
accomplishment, and neither falls strictly within the realms of the arts
or sciences. But what a pair they are. The first is the fully realized
conceptualization of monotheism, expressed through one of the literary
treasures of the world, the Hebrew Bible. It not only laid the
foundation for three great religions but, as Thomas Cahill describes in
The Gifts of the Jews (1998), introduced a way of looking at the meaning
of human life and the nature of history that defines core elements of
the modern sensibility....
But religious literature is the
exception. The Jews do not appear in the annals of philosophy, drama,
visual art, mathematics, or the natural sciences during the eighteen
centuries from the time of Homer through the first millennium C.E., when
so much was happening in Greece, China, and South Asia. It is unclear
to what extent this reflects a lack of activity or the lack of a readily
available record. For example, only a handful of the scientists of the
Middle Ages are mentioned in most histories of science, and none was a
Jew. But when George Sarton put a high-powered lens to the Middle Ages
in his monumental Introduction to the History of Science (1927-48), he
found that 95 of the 626 known scientists working everywhere in the
world from 1150 to 1300 were Jews—15 percent of the total, far out of
proportion to the Jewish population.
As it happens, that same period overlaps
with the life of the most famous Jewish philosopher of medieval times,
Maimonides (1135–1204), and of others less well known, not to mention
the Jewish poets, grammarians, religious thinkers, scholars, physicians,
and courtiers of Spain in the “Golden Age,” or the brilliant exegetes
and rabbinical legislators of northern France and Germany. But this only
exemplifies the difficulty of assessing Jewish intellectual activity in
that period. Aside from Maimonides and a few others, these thinkers and
artists did not perceptibly influence history or culture outside the
confines of the Jewish world.
Generally speaking, this remained the
case well into the Renaissance and beyond. When writing a book called
Human Accomplishment (2003), I compiled inventories of “significant
figures” in the arts and sciences, defined as people who are mentioned
in at least half of the major histories of their respective fields. From
1200 to 1800, only seven Jews are among those significant figures, and
only two were important enough to have names that are still widely
recognized: Spinoza and Montaigne (whose mother was Jewish).
_____________
The sparse representation of Jews during
the flowering of the European arts and sciences is not hard to explain.
They were systematically excluded, both by legal restrictions on the
occupations they could enter and by savage social discrimination. Then
came legal emancipation, beginning in the late 1700’s in a few countries
and completed in Western Europe by the 1870’s, and with it one of the
most extraordinary stories of any ethnic group at any point in human
history.
As soon as Jewish children born under
legal emancipation had time to grow to adulthood, they started appearing
in the first ranks of the arts and sciences. During the four decades
from 1830 to 1870, when the first Jews to live under emancipation
reached their forties, 16 significant Jewish figures appear. In the next
four decades, from 1870 to 1910, the number jumps to 40. During the
next four decades, 1910–1950, despite the contemporaneous devastation of
European Jewry, the number of significant figures almost triples, to
114.
To get a sense of the density of
accomplishment these numbers represent, I will focus on 1870 onward,
after legal emancipation had been achieved throughout Central and
Western Europe. How does the actual number of significant figures
compare to what would be expected given the Jewish proportion of the
European and North American population? From 1870 to 1950, Jewish
representation in literature was four times the number one would expect.
In music, five times. In the visual arts, five times. In biology, eight
times. In chemistry, six times. In physics, nine times. In mathematics,
twelve times. In philosophy, fourteen times.
Disproportionate Jewish accomplishment
in the arts and sciences continues to this day. My inventories end with
1950, but many other measures are available, of which the best known is
the Nobel Prize. In the first half of the 20th century, despite
pervasive and continuing social discrimination against Jews throughout
the Western world, despite the retraction of legal rights, and despite
the Holocaust, Jews won 14 percent of Nobel Prizes in literature,
chemistry, physics, and medicine/physiology. In the second half of the
20th century, when Nobel Prizes began to be awarded to people from all
over the world, that figure rose to 29 percent. So far, in the 21st
century, it has been 32 percent. Jews constitute about two-tenths of one
percent of the world’s population. You do the math.
_____________
What accounts for this remarkable
record? A full answer must call on many characteristics of Jewish
culture, but intelligence has to be at the center of the answer. Jews
have been found to have an unusually high mean intelligence as measured
by IQ tests since the first Jewish samples were tested. (The widely
repeated story that Jewish immigrants to this country in the early 20th
century tested low on IQ is a canard.) Exactly how high has been
difficult to pin down, because Jewish sub-samples in the available
surveys are seldom perfectly representative. But it is currently
accepted that the mean is somewhere in the range of 107 to 115, with 110
being a plausible compromise.
The IQ mean for the American population
is “normed” to be 100, with a standard deviation of 15. If the Jewish
mean is 110, then the mathematics of the normal distribution says that
the average Jew is at the 75th percentile. Underlying that mean in
overall IQ is a consistent pattern on IQ subtests: Jews are only about
average on the subtests measuring visuo-spatial skills, but extremely
high on subtests that measure verbal and reasoning skills.
A group’s mean intelligence is important
in explaining outcomes such as mean educational attainment or mean
income. The key indicator for predicting exceptional accomplishment
(like winning a Nobel Prize) is the incidence of exceptional
intelligence. Consider an IQ score of 140 or higher, denoting the level
of intelligence that can permit people to excel in fields like
theoretical physics and pure mathematics. If the mean Jewish IQ is 110
and the standard deviation is 15, then the proportion of Jews with IQ’s
of 140 or higher is somewhere around six times the proportion of
everyone else.
The imbalance continues to increase for
still higher IQ’s. New York City’s public-school system used to
administer a pencil-and-paper IQ test to its entire school population.
In 1954, a psychologist used those test results to identify all 28
children in the New York public-school system with measured IQ’s of 170
or higher. Of those 28, 24 were Jews.
Exceptional intelligence is not enough
to explain exceptional accomplishment. Qualities such as imagination,
ambition, perseverance, and curiosity are decisive in separating the
merely smart from the highly productive. The role of intelligence is
nicely expressed in an analogy suggested to me years ago by the
sociologist Steven Goldberg: intelligence plays the same role in an
intellectually demanding task that weight plays in the performance of
NFL offensive tackles. The heaviest offensive tackle is not necessarily
the best. Indeed, the correlation between weight and performance among
NFL offensive tackles is probably quite low. But they all weigh more
than 300 pounds.
So with intelligence. The other things
count, but you must be very smart to have even a chance of achieving
great work. A randomly selected Jew has a higher probability of
possessing that level of intelligence than a randomly selected member of
any other ethnic or national group, by far.
_____________
Nothing that I have presented up to this
point is scientifically controversial. The profile of
disproportionately high Jewish accomplishment in the arts and sciences
since the 18th century, the reality of elevated Jewish IQ, and the
connection between the two are not to be denied by means of data. And so
we come to the great question: how and when did this elevated Jewish IQ
come about? Here, the discussion must become speculative. Geneticists
and historians are still assembling the pieces of the explanation, and
there is much room for disagreement.
I begin with the assumption that
elevated Jewish intelligence is grounded in genetics. It is no longer
seriously disputed that intelligence in Homo sapiens is substantially
heritable. In the last two decades, it has also been established that
obvious environmental factors such as high income, books in the house,
and parental reading to children are not as potent as one might expect. A
“good enough” environment is important for the nurture of intellectual
potential, but the requirements for “good enough” are not high. Even the
very best home environments add only a few points, if that, to a merely
okay environment. It is also known that children adopted at birth do
not achieve the IQ’s predicted by their parents’ IQ.
To put it another way, we have good
reason to think that Gentile children raised in Jewish families do not
acquire Jewish intelligence. Hence my view that something in the genes
explains elevated Jewish IQ. That conclusion is not logically necessary
but, given what we know about heritability and environmental effects on
intelligence in humans as a species, it is extremely plausible.
Two potential explanations for a Jewish
gene pool favoring high intelligence are so obvious that many people
assume they must be true: winnowing by persecution (only the smartest
Jews either survived or remained Jews) and marrying for brains (scholars
and children of scholars were socially desirable spouses). I too think
that both of these must have played some role, but how much of a role is
open to question.
In the case of winnowing through
persecution, the logic cuts both ways. Yes, those who remained faithful
during the many persecutions of the Jews were self-selected for
commitment to Judaism, and the role of scholarship in that commitment
probably means that intelligence was one of the factors in
self-selection. The foresight that goes with intelligence might also
have had some survival value (as in anticipating pogroms), though it is
not obvious that its effect would be large enough to explain much.
But once the Cossacks are sweeping
through town, the kind of intelligence that leads to business success or
rabbinical acumen is no help at all. On the contrary, the most
successful people could easily have become the most likely to be killed,
by virtue of being more visible and the targets of greater envy.
Furthermore, other groups, such as the Gypsies, have been persecuted for
centuries without developing elevated intelligence. Considered closely,
the winnowing-by-persecution logic is not as compelling as it may first
appear.
What of the marrying-for-brains theory?
“A man should sell all he possesses in order to marry the daughter of a
scholar, as well as to marry his daughter to a scholar,” advises the
Talmud (Pesachim 49a), and scholarship did in fact have social cachet
within many Jewish communities before (and after) emancipation. The
combination could have been potent: by marrying the children of scholars
to the children of successful merchants, Jews were in effect joining
those selected for abstract reasoning ability with those selected for
practical intelligence.
Once again, however, it is difficult to
be more specific about how much effect this might have had. Arguments
have been advanced that rich merchants were in fact often reluctant to
entrust their daughters to penniless and unworldly scholars. Nor is it
clear that the fertility rate of scholars, or their numbers, were high
enough to account for a major effect on intelligence. The attractiveness
of brains in prospective marriage partners surely played some role but,
once again, the data for assessing how much have not been assembled.
_____________
Against this backdrop of uncertainty, a
data-driven theory for explaining elevated Jewish IQ appeared in 2006 in
the Journal of Biosocial Science. In an article entitled “Natural
History of Ashkenazi Intelligence,” Gregory Cochran (a physicist) and
Jason Hardy and Henry Harpending (anthropologists) contend that elevated
Jewish IQ is confined to the Ashkenazi Jews of northern and central
Europe, and developed from the Middle Ages onward, primarily from 800 to
1600 C.E.
In the analysis of these authors, the
key factor explaining elevated Jewish intelligence is occupational
selection. From the time Jews became established north of the
Pyrenees-Balkans line, around 800 C.E., they were in most places and at
most times restricted to occupations involving sales, finance, and
trade. Economic success in all of these occupations is far more highly
selected for intelligence than success in the chief occupation of
non-Jews: namely, farming. Economic success is in turn related to
reproductive success, because higher income means lower infant
mortality, better nutrition, and, more generally, reproductive
“fitness.” Over time, increased fitness among the successful leads to
strong selection for the cognitive and psychological traits that produce
that fitness, intensified when there is a low inward gene flow from
other populations—as was the case with Ashkenazim.
Sephardi and Oriental Jews—i.e., those
from the Iberian peninsula, the Mediterranean littoral, and the Islamic
East—were also engaged in urban occupations during the same centuries.
But the authors cite evidence that, as a rule, they were less
concentrated in occupations that selected for IQ and instead more
commonly worked in craft trades. Thus, elevated intelligence did not
develop among Sephardi and Oriental Jews—as manifested by contemporary
test results in Israel that show the IQ’s of non-European Jews to be
roughly similar to the IQ’s of Gentiles.
The three authors conclude this part of
their argument with an elegant corollary that matches the known test
profiles of today’s Ashkenazim with the historical experience of their
ancestors:
The suggested selective process explains
the pattern of mental abilities in Ashkenazi Jews: high verbal and
mathematical ability but relatively low spatio-visual ability. Verbal
and mathematical talent helped medieval businessmen succeed, while
spatio-visual abilities were irrelevant.
The rest of their presentation is a
lengthy and technical discussion of the genetics of selection for IQ,
indirect evidence linking elevated Jewish IQ with a variety of
genetically based diseases found among Ashkenazim, and evidence that
most of these selection effects have occurred within the last 1,200
years.
_____________
No one has yet presented an alternative
to the Cochran-Hardy-Harpending theory that can match it for
documentation. But, as someone who suspects that elevated Jewish
intelligence was (a) not confined to Ashkenazim and (b) antedates the
Middle Ages, I will outline the strands of an alternative explanation
that should be explored.
It begins with evidence that Jews who
remained in the Islamic world exhibited unusually high levels of
accomplishment as of the beginning of the second millennium. The hardest
evidence is Sarton’s enumeration of scientists mentioned earlier, of
whom 15 percent were Jews. These were not Ashkenazim in northern Europe,
where Jews were still largely excluded from the world of scientific
scholarship, but Sephardim in the Iberian peninsula, in Baghdad, and in
other Islamic centers of learning. I have also mentioned the more
diffuse cultural evidence from Spain, where, under both Muslim and
Christian rule, Jews attained eminent positions in the professions,
commerce, and government as well as in elite literary and intellectual
circles.
After being expelled from Spain at the
end of the 15th century, Sephardi Jews rose to distinction in many of
the countries where they settled. Some economic historians have traced
the decline of Spain after 1500, and the subsequent rise of the
Netherlands, in part to the Sephardi commercial talent that was
transferred from the one to the other. Centuries later, in England, one
could point to such Sephardi eminences as Benjamin Disraeli and the
economist David Ricardo.
In sum, I propose that a strong case
could be assembled that Jews everywhere had unusually high intellectual
resources that manifested themselves outside of Ashkenaz and well before
the period when non-rabbinic Ashkenazi accomplishment manifested
itself.
How is this case to be sustained in the
face of contemporary test data indicating that non-Ashkenazi Jews do not
have the elevated mean of today’s Ashkenazim? The logical inconsistency
disappears if one posits that Jews circa 1000 C.E. had elevated
intelligence everywhere, but that it subsequently was augmented still
further among Ashkenazim and declined for Jews living in the Islamic
world—perhaps because of the dynamics described by Cochran, Hardy, and
Harpending (that is, Oriental Jews were concentrated in trades for which
high intelligence did not yield wealth).
Recent advances in the use of genetic
markers to characterize populations enable us to pursue such
possibilities systematically. I offer this testable hypothesis as just
one of many possibilities: if genetic markers are used to discriminate
among non- Ashkenazi Jews, it will be found that those who are closest
genetically to the Sephardim of Golden Age Spain have an elevated mean
IQ, though perhaps not so high as the contemporary Ashkenazi IQ.
_____________
The next strand of an alternative to the
Cochran-Hardy-Harpending theory involves reasons for thinking that some
of the elevation of Jewish intelligence occurred even before Jews moved
into occupations selected for intelligence, because of the shift in
ancient Judaism from a rite-based to a learning-based religion.
All scholars who have examined the topic
agree that about 80–90 percent of all Jews were farmers at the
beginning of the Common Era, and that only about 10–20 percent of Jews
were farmers by the end of the first millennium. No other ethnic group
underwent this same kind of occupational shift. For the story of why
this happened, I turn to a discussion by Maristella Botticini and Zvi
Eckstein entitled “Jewish Occupational Selection: Education,
Restrictions, or Minorities?” which appeared in the Journal of Economic
History in 2005.
Rejecting the explanation that Jews
became merchants because they were restricted from farming, Botticini
and Eckstein point to cases in which Jews who were free to own land and
engage in agriculture made the same shift to urban, skilled occupations
that Jews exhibited where restrictions were in force. Instead, they
focus on an event that occurred in 64 C.E., when the Palestinian sage
Joshua ben Gamla issued an ordinance mandating universal schooling for
all males starting at about age six. The ordinance was not only issued;
it was implemented. Within about a century, the Jews, uniquely among the
peoples of the world, had effectively established universal male
literacy and numeracy.
The authors’ explanation for the
subsequent shift from farming to urban occupations reduces to this: if
you were educated, you possessed an asset that had economic value in
occupations that required literacy and numeracy, such as those involving
sales and transactions. If you remained a farmer, your education had
little or no value. Over the centuries, this basic economic reality led
Jews to leave farming and engage in urban occupations.
So far, Botticini and Eckstein have
provided an explanatory backdrop to the shift in occupations that in
turn produced the selection pressures for intelligence described by
Cochran, Hardy, and Harpending. But selection pressure in this classic
form was probably not the only force at work. Between the 1st and 6th
centuries C.E., the number of Jews in the world plummeted from about 4.5
million to 1.5 million or fewer. About 1 million Jews were killed in
the revolts against the Romans in Judea and Egypt. There were scattered
forced conversions from Judaism to another religion. Some of the
reduction may be associated with a general drop in population that
accompanied the decline and fall of the Roman Empire. But that still
leaves a huge number of Jews who just disappeared.
What happened to them? Botticini and
Eckstein argue that an economic force was at work: for Jews who remained
farmers, universal education involved a cost that had little economic
benefit. As time went on, they drifted away from Judaism. I am sure this
explanation has some merit. But a more direct explanation could involve
the increased intellectual demands of Judaism.
Joshua ben Gamla’s ordinance mandating
literacy occurred at about the same time as the destruction of the
Second Temple—64 C.E. and 70 C.E., respectively. Both mark the moment
when Judaism began actively to transform itself from a religion centered
on rites and sacrifices at the Temple in Jerusalem to a religion
centered on prayer and the study of the Torah at decentralized
synagogues and study houses. Rabbis and scholars took on a much larger
role as leaders of local communities. Since worship of God involved not
only prayer but study, all Jewish males had to read if they were to
practice their faith—and not only read in private but be able to read
aloud in the presence of others.
In this context, consider the
intellectual requirements of literacy. People with modest intelligence
can become functionally literate, but they are able to read only simple
texts. The Torah and the Hebrew prayer book are not simple texts; even
to be able to read them mechanically requires fairly advanced literacy.
To study the Talmud and its commentaries with any understanding requires
considerable intellectual capacity. In short, during the centuries
after Rome’s destruction of the Temple, Judaism evolved in such a way
that to be a good Jew meant that a man had to be smart.
What happened to the millions of Jews
who disappeared? It is not necessary to maintain that Jews of low
intelligence were run out of town because they could not read the Torah
and commentaries fluently. Rather, few people enjoy being in a position
where their inadequacies are constantly highlighted. It is human nature
to withdraw from such situations. I suggest that the Jews who fell away
from Judaism from the 1st to 6th centuries C.E. were heavily
concentrated among those who could not learn to read well enough to be
good Jews—meaning those from the lower half of the intelligence
distribution. Even before the selection pressures arising from urban
occupations began to have an effect, I am arguing, the remaining
self-identified Jews circa 800 C.E. already had elevated intelligence.
_____________
A loose end remains. Is it the case
that, before the 1st century C.E., Jews were intellectually ordinary?
Are we to believe that the Bible, a work compiled over centuries and
incorporating everything from brilliant poetry to profound ethics, with
stories that speak so eloquently to the human condition that they have
inspired great art, music, and literature for millennia, was produced by
an intellectually run-of-the-mill Levantine tribe?
In The Evolution of Man and Society
(1969), the geneticist Cyril Darlington presented the thesis that Jews
and Judaism were decisively shaped much earlier than the 1st century
C.E., namely, by the Babylonian captivity that began with the fall of
Jerusalem to the forces of Nebuchadnezzar in 586 B.C.E.
Darlington’s analysis touches on many
issues, but I will focus on just the intelligence question. The biblical
account clearly states that only a select group of Jews were taken to
Babylon. We read that Nebuchadnezzar “carried into exile all Jerusalem:
all the officers and fighting men, and all the craftsmen and artisans. .
. . Only the poorest people of the land were left” (2 Kings 24:10).
In effect, the Babylonians took away the
Jewish elites, selected in part for high intelligence, and left behind
the poor and unskilled, selected in part for low intelligence. By the
time the exiles returned, more than a century later, many of those
remaining behind in Judah had been absorbed into other religions.
Following Ezra’s command to “separate yourselves from the peoples around
you and from your foreign wives” (Ezra 10:9), only those who renounced
their foreign wives and children were permitted to stay within the
group. The returned exiles, who formed the bulk of the reconstituted
Jewish community, comprised mainly the descendants of the Jewish
elites—plausibly a far more able population, on average, than the
pre-captivity population.
I offer the Babylonian captivity as a
concrete mechanism whereby Jewish intelligence may have been elevated
very early, but I am not wedded to it. Even without that mechanism,
there is reason to think that selection for intelligence antedates the
1st century C.E.
From its very outset, apparently going
back to the time of Moses, Judaism was intertwined with intellectual
complexity. Jews were commanded by God to heed the law, which meant they
had to learn the law. The law was so extensive and complicated that
this process of learning and reviewing was never complete. Moreover,
Jewish males were not free to pretend that they had learned the law, for
fathers were commanded to teach the law to their children. It became
obvious to all when fathers failed in their duty. No other religion made
so many intellectual demands upon the whole body of its believers. Long
before Joshua ben Gamla and the destruction of the Second Temple, the
requirements for being a good Jew had provided incentives for the less
intelligent to fall away.
Assessing the events of the 1st century
C.E. thus poses a chicken-and-egg problem. By way of an analogy,
consider written Chinese with its thousands of unique characters. On
cognitive tests, today’s Chinese do especially well on visuo-spatial
skills. It is possible, I suppose, that their high visuo-spatial skills
have been fostered by having to learn written Chinese; but I find it
much more plausible that only people who already possessed high
visuo-spatial skills would ever devise such a ferociously difficult
written language. Similarly, I suppose it is possible that the Jews’
high verbal skills were fostered, through secondary and tertiary
effects, by the requirement that they be able to read and understand
complicated texts after the 1st century C.E.; but I find it much more
plausible that only people who already possessed high verbal skills
would dream of installing such a demanding requirement.
This reasoning pushes me even farther
into the realm of speculation. Insofar as I am suggesting that the Jews
may have had some degree of unusual verbal skills going back to the time
of Moses, I am naked before the evolutionary psychologists’ ultimate
challenge. Why should one particular tribe at the time of Moses, living
in the same environment as other nomadic and agricultural peoples of the
Middle East, have already evolved elevated intelligence when the others
did not?
At this point, I take sanctuary
in my remaining hypothesis, uniquely parsimonious and happily
irrefutable. The Jews are God’s chosen people.
About the Author: Charles Murray is the
W.H. Brady scholar at the American Enterprise Institute and the author
most recently of In Our Hands: A Plan to Replace the Welfare State
(2006). This article has been adapted from a presentation at the annual
Herzliya Conference in Israel in January.
