# Book review: WEIRDest People

Book review: The WEIRDest People in the World, by Joseph Henrich.

Wow!

Henrich previously wrote [one of the best books of the last
decade](http://www.bayesianinvestor.com/blog/index.php/2016/04/13/the-secret-of-our-success/).
Normally, I expect such an author\'s future books to, at best, exhibit
regression toward the mean. But Henrich\'s grand overview of humanity\'s
first few million years was merely a modest portion of the ideas that he
originally tried to fit into this magnum opus. Henrich couldn\'t quite
explain in one volume how humanity got all the way to industrial
empires, so he split the explanation into two books.

The cartoon version of the industrial revolution: Protestant culture
made the West more autistic.

However, explaining the [most important event in
history](https://lukemuehlhauser.com/industrial-revolution/) makes up
only about 25% of this book\'s focus and value.

Henrich doesn\'t want us to think of it as the most important event -
because he views it not as a single event, but as a stage in a long
process. Most books on the industrial revolution concentrate on some
subset of the 1500-1800 time frame. WEIRDest People devotes a majority
of its attention to the prior millennium.

When I [last reviewed a
book](http://www.bayesianinvestor.com/blog/index.php/2017/04/13/state-economy-and-the-great-divergence/)
on the industrial revolution, I was pessimistic about ever getting
enough evidence to distinguish between too many plausible hypotheses.
Henrich found a solution: most of the proposed explanations describe
features that contributed to the industrial revolution; they follow
naturally from the way that WEIRD culture (Western, Educated,
Industrialized, Rich, Democratic) altered our psychology.

Important aspects of this new culture / psychology include: analytic
thinking, nonconformity, impersonal prosociality (trusting strangers,
treating them fairly), and internal attributions (e.g. the idea that a
good afterlife depends on internal mental states, rather than rituals).

Along the way, Henrich provides at least partial answers to a surprising
number of questions that I carelessly neglected to ask, such as:

-   how do rules about cousin marriage affect conformity (as measured by
    the Asch Conformity Test)?
-   how strong is the correlation between how individualistic a society
    is and its rate of innovation?
-   why does Latin have 25 words for prostitute?
-   how did the peculiarities of rice cultivation affect the ability of
    southeastern China to develop science?
-   how do social safety nets influence a society\'s rate of innovation?

Much of Henrich\'s focus is on this key question: how do increasingly
large groups of people cooperate enough to form increasingly large
societies?

### The Dunbar Number and its cousins

There\'s a phenomenon that is somewhat well known among financial
traders of a limit of about 20 stocks, beyond which traders can\'t
remain sufficiently aware of the details to be a competent market maker.

Henrich describes what is likely another manifestation of the same
phenomenon in \"truly individualistic\" human cultures, such as [the
Matsigenka](https://www.goodreads.com/book/show/2772673-families-of-the-forest),
where hamlets rarely get as large as 25 people before nuclear families
decide they prefer to set off on their own.

I\'ve also noticed a seemingly similar phenomenon in business,
particularly in a dot-com where I worked that rapidly grew from 4 to 75
people. At some point between the 20 person size and 40 person size, it
switched from feeling like users were part of the company\'s community,
to a feeling that users were distant people who were dealt with via
specialists such as customer service. Also, internal politics went from
not being detectable, to being important.

Sadly, Henrich doesn\'t mention a name for this 20-25 entity limit. Nor
does he name the Dunbar Number, despite providing important insights
into how cultures manage to create social groups that are bigger than
the Dunbar Number.

Dunbar-sized tribes often end up with rituals that artificially create
interdependence and kin-like bonds that help hold the tribe together.

Switching from a system of bilineal descent to [unilineal
descent](https://en.wikipedia.org/wiki/Unilineality) prevents some kinds
of conflicts between extended families.

Some other norms that promote harmony in large villages include:
arranged marriages, making entire clans responsible for harm caused by
any clan member, and well-defined hierarchies.

### The Evolution of Religion

There\'s at least one more size limit, well above the Dunbar Number,
where rituals that expand kinship become inadequate for further
expansion. To overcome that, societies needed [Big
Gods](https://www.goodreads.com/book/show/17942053-big-gods) who can
command subjects to cooperate with distant co-religionists.

Belief in heaven and hell [correlates
with](https://www.aeaweb.org/articles?id=10.1257/jep.20.2.49) (and
likely causes) a large increase in economic growth. Alas, belief in
heaven alone doesn\'t seem to be very valuable.

A [similar pattern is
seen](https://royalsocietypublishing.org/doi/full/10.1098/rspb.2014.2556)
for belief in supernatural punishment in societies before European
contact.

> The estimated probability of a historical transition to a complex
> chiefdom when no such punishment existed was - surprisingly - close to
> zero. By contrast, when ancestral communities already had beliefs in
> supernatural punishments for important moral violations, there was a
> roughly 40% chance of scaling up in complexity every three centuries
> or so.

Those religions succeeded better if they destroyed the kinship
institutions that had previously been needed for scaling up past the
Dunbar Number.

Why? Kin-based clans interfered with loyalty to larger, more abstract
groups such as Christianity or nations. Here\'s a quote from a
politician in contemporary Pakistan that illustrates how kin-based group
identity conflicts with newer, larger social groups:

> I have been a Pashtun for six thousand years, a Muslim for thirteen
> hundred years, and a Pakistani for twenty-five.

How? By changing many rules involving marriage and family relations.
That included banning the marriages between cousins (a ban which
sometimes extended to sixth cousins), and requiring monogamy.

Don\'t assume you can design your own religion:

> the powerful Mughal emperor Akbar the Great tried to unify his Muslim
> and Hindu subjects by making his own highly tolerant religious creed
> \... At its peak, the powerful emperor\'s religion accumulated a total
> of only 18 prominent adherents before vanishing into history. My point
> is that throughout human history, rulers needed religion much more
> than religion needed rulers.

I sometimes got the feeling that the Western Christian church\'s success
at stamping out kin-based institutions had to be mostly due to careful
planning and foresight, but Henrich implies that\'s mostly hindsight
bias, and calls the process \"accidental genius\". Henrich has good
arguments that cultural evolution includes an important amount of
semi-blind trial and error, but I suspect he goes a bit overboard with
this line of thought.

E.g. [Deuteronomy
25:5-10](https://www.biblegateway.com/passage/?search=Deuteronomy%2025%3A5-10&version=NIV)
clearly describes [levirate
marriage](https://en.wikipedia.org/wiki/Levirate_marriage) as an
obligation. How does unplanned exploration of cultural variation get
from there to declaring levirate marriage a sin, while still treating
the bible as the word of God?

Fukuyama has a better model for that than Henrich: in [The Origins of
Political
Order:](http://www.bayesianinvestor.com/blog/index.php/2013/06/26/the-origins-of-political-order/),
he implies that the church had a fairly deliberate strategy of
destroying the kinship ties that were hindering the church\'s goal of
inheriting property. Note that it\'s fairly WEIRD of me to care about
whether the church\'s strategies were intentional.

### Faster Cultural Evolution

Kin-based societies have strong constraints on who people can associate
with. Accidents of birth, plus arranged marriages, mostly determine who
a person will interact with. Cooperation between kin works fairly well,
but distrust hinders most cooperation outside of the clan.

Early Western culture caused many clan-oriented social interactions to
wither, creating some desire for new types of interactions. It also made
people more independent and trusting of strangers, which enabled a wide
variety of voluntary organizations to develop, such as guilds, charter
towns, monasteries, and universities.

Monasteries morphed from clan businesses to NGO-like organizations.
Guilds had to compete with goods from similar guilds in nearby towns.
Most organizations competed for new members. Cities needed to experiment
with better governance (including some democracy) in order to offset the
[urban graveyard
effect](https://left.wikia.org/wiki/Urban_graveyard_effect).

That competition may not seem like much, but it seems to have been more
than was possible in China / India / Islam. It likely contributed to
faster experimentation and vetting of new cultural features.

### Flynn Effect

The power of Henrich\'s model can be illustrated by asking how it
explains the big 20th century increase in IQ. Henrich doesn\'t discuss
this topic directly, but if I\'d read WEIRDest People before learning of
the Flynn Effect, I expect I would have found the Flynn Effect
unsurprising. It seems like a natural consequence of thinking styles
that became more analytical, abstract, reductionist, and numerical.

Moreover, Henrich\'s model provides clues as to why low-IQ cultures are
reluctant to adopt the changes that raise their IQs. It\'s not that
they\'re lazy or held back by harmful mutations (Henrich doesn\'t
dismiss the existence of those problems; instead, he convinced me that
WEIRD culture shifts are more powerful explanations).

An important insight is that people take cues from their environment
early in life, and use those cues to invest in cognitive features that
are expected to yield the most benefit.

WEIRD culture gets people to invest more in high-IQ cognitive features,
at the cost of less investment in skills that foster social ties (e.g.
learning to read at early age seems to [impair facial
recognition](https://www.nature.com/articles/nrn3924)). \"WEIRD people
are bad friends\" - beliefs such as impartial rules, and moral
universalism have important social consequences. E.g. WEIRD people are
less willing to lie in court to keep their friends out of jail. It looks
hard to separate that effect from the cognitive styles that promote high
IQ.

There are also trade-offs between analytical thinking and holistic
thinking. IQ tests tend to favor the analytical approach that Western
societies reward, while kin-based societies reward holistic thinking
more (see [Ecocultural basis of cognition: Farmers and fishermen are
more holistic than herders](https://www.pnas.org/content/105/25/8552)).

### Comparison with Related Explanations

Many other books on the industrial revolution now sound like the
proverbial [blind men and an
elephant](https://en.wikipedia.org/wiki/Blind_men_and_an_elephant).

-   In [The Origins of Political
    Order:](http://www.bayesianinvestor.com/blog/index.php/2013/06/26/the-origins-of-political-order/),
    Fukuyama sees about 20% of what Henrich sees, and is the only person
    I\'m aware of that traces the origins of key features further back
    than does Henrich. Fukuyama also explains better why the industrial
    revolution happened in Europe rather than China. This now looks like
    clearly the second most important book on the industrial revolution.
-   [State, Economy, and the Great
    Divergence](http://www.bayesianinvestor.com/blog/index.php/2017/04/13/state-economy-and-the-great-divergence/):
    Great Britain and China, 1680s - 1850s, by Peer Vries identifies a
    modest fraction of the cultural differences that Henrich discusses.
    Vries seems to disagree with Henrich about the mobility of the
    average British worker, but otherwise supports Henrich more than I
    recalled. Vries\' expertise as a historian lends credence to
    Henrich. I wish I had time to carefully recheck the extent to which
    Vries\' evidence supports Henrich, but Vries is hard to read.
-   Nick Szabo\'s [Book
    Consciousness](http://unenumerated.blogspot.com/2006/08/book-consciousness.html)
    explanation captures a medium-sized portion of Henrich\'s vision,
    and the two complement each other fairly well.
-   [A Farewell to
    Alms](http://www.bayesianinvestor.com/blog/index.php/2007/10/01/farewell-to-alms/),
    by Gregory Clark seems a bit like WEIRDest People, with lots of
    tension between their details and tone. [Bryan Caplan\'s
    objection](https://www.econlib.org/archives/2007/09/a_farewell_to_a.html)
    illustrates some of this:

    > Why are rich countries so much richer than poor countries,
    > according to Clark? Because they have lower-quality workers.
    >
    > Obvious objection: If that's the problem, why does moving these
    > low-quality workers to the West quickly raise their wages from
    > \$1/day to \$40/day? Yes, that's below average for the West, but
    > it's in the same ballpark. If that isn't iron-clad proof that
    > institutions/policy matter a lot, what is?

    Henrich resolves this dispute by convincing me that \"lower-quality
    workers\" means workers whose culture and psychology are poorly
    adapted to most modern jobs. Clark\'s arguments could be modified to
    accommodate that view without drastic changes.

-   [The Birth of
    Plenty](http://www.bayesianinvestor.com/blog/index.php/2008/04/08/the-birth-of-plenty/)
    by William Bernstein presents a view of institutions circa 1800 that
    mostly agrees with what Henrich considers to be important for the
    industrial revolution, but Bernstein\'s attempts at explaining how
    the West got there seem rather pathetic in comparison to Henrich\'s.
-   [The Great
    Divergence](http://www.bayesianinvestor.com/blog/index.php/2005/11/23/the-great-divergence/):
    China, Europe, and the Making of the Modern World Economy, by
    Kenneth Pomeranz raised the bar by pointing out that leading
    discussions of the industrial revolution failed to explain why
    Europe did better than China, but Pomeranz went overboard in
    claiming those two regions were similar. Pomeranz tried to argue
    against cultural explanations in general, but seemed confused as to
    how culture could explain more than differences in luxury goods.
    Were older cultural explanations (such as Max Weber\'s?) really that
    weak?
-   [How the West
    Won](http://www.bayesianinvestor.com/blog/index.php/2014/09/08/how-the-west-won/)
    by Rodney Stark may share some of Henrich\'s attitudes, but I\'ve
    mostly forgotten what Stark wrote because he wasn\'t very
    convincing.
-   [Where Is My Flying
    Car?](http://www.bayesianinvestor.com/blog/index.php/2018/10/14/where-is-my-flying-car/)
    by J. Storrs Hall almost sounds like a sequel to Henrich\'s books,
    explaining how Western culture is decaying due to problems such as
    Christianity being replaced by religions that are less well adapted
    to modernity. Henrich has increased my confidence that Where is my
    Flying Car? is more than half-right about the causes of the Great
    Stagnation.
-   I see a strange parallel to Marxism when Henrich describes the need
    for societies to go through different, partly opposing (dialectic),
    stages. But Henrich is the opposite of a Marxist in many other
    respects, such as the ability of intellectual leaders to predict
    those stages.

### How Credible?

I\'ll guess that the book is about 80% correct.

Henrich exaggerates and oversimplifies a modest amount, but he seems to
be a pretty careful researcher, actively trying to find empirical tests
of alternate causal models.

He often cites evidence that isn\'t especially compelling, but he\'s
careful not to depend much on any one piece of evidence. E.g. he
apologizes for only being able to cite one study each for the claims
that the [BIG-5 personality
dimensions](https://pubmed.ncbi.nlm.nih.gov/23245291/) and [endowment
effect](https://www.aeaweb.org/articles?id=10.1257/aer.104.6.1793) are
not universal.

The book is somewhat limited by only having a sample size of one for
some of his broadest claims, but Henrich manages to find a larger sample
size for many interesting sub-points.

E.g. I had assumed that China\'s one-child policy was tricky to evaluate
because it was only imposed once. Yet Henrich points us to [Sex ratios
and crime: Evidence from
China](http://www.columbia.edu/~le93/EdlundLiYiZhang13.pdf), showing
that we can get sort-of-causal evidence from comparing provinces that
implemented the policy in different years. Yes, it sure looks like the
policy caused crime to increase (the policy may have also had desirable
effects via weakening kinship ties - Henrich doesn\'t express any
overall opinion on the policy).

Henrich has a [remarkable range of
expertise](https://en.wikipedia.org/wiki/Joseph_Henrich) (anthropology,
evolutionary biology, engineering, psychology, and economics); these
maybe make him better than a historian for the purpose of this book.

Historians [are apparently
upset](https://www.historians.org/publications-and-directories/perspectives-on-history/may-2020/weird-science-incest-and-history)
at being bypassed, and at the inadequate nuance of a shorter version of
WEIRDest People, but their disagreements don\'t sound particularly
important to me.

If you\'re still undecided about whether to read the book, a fair amount
of Henrich\'s evidence is available [in this
preprint](https://psyarxiv.com/d6qhu/).

### Conclusion

This book is essential reading for any serious scholar of human nature.

Not only does it demystify some of the most important processes of human
history, but it also provides an unusually balanced view of how Western
culture compares to other cultures. Henrich discredits both \"all
cultures are equal\" worldviews, and most of the common claims of
Western superiority. Western culture is genuinely superior in key
respects, but that superiority comes with possibly large downsides.

Henrich is a master at organizing large amounts of evidence into an
understandable package.

Please don\'t treat this review as an adequate substitute for reading
the book. I can\'t describe enough of Henrich\'s model to sound half as
convincing as Henrich\'s full description is. I only hope to whet your
appetite enough to convince you to read the book.

P.S. I was maybe a bit misleading when I used the word autistic to
describe the psychological changes that Henrich attributes to
Christianity / Protestantism. I can\'t confirm that he\'s even familiar
with autism. I find it to be a convenient label to approximate his more
nuanced, but hard to summarize, description of Western psychology.