Book review: How the World Became Rich: The Historical Origins of Economic Growth, by Mark Koyama and Jared Rubin.
This is a well-written review of why different countries have different wealth, i.e. mostly about the industrial revolution.
The authors predominantly adopt an economist’s perspective, and somewhat neglect the perspective of historians, but manage to fairly present most major viewpoints.
Continue ReadingBook review: The British Industrial Revolution in Global Perspective, by Robert C. Allen.
Here we have yet another explanation of the most important event in history, this time from an economic historian.
Allen mostly focuses on one key piece of the causal chain: British wages were high compared to the cost of energy.
Nearly everything he says seems correct, but I have some medium-sized complaints about what he neglects.
British wages were higher than those of just about any other country, at least after 1575. That was an important component in Britain’s lead at producing technological innovation. The initial steps in many key technological advances were crude enough that they wouldn’t have made sense if they were competing with cheap labor.
It seems important to focus on what caused the high wages. Allen is a bit weak here.
He mentions British diets, mostly as evidence of high British wages. But he also hints that the high calorie, high protein diet enabled higher productivity, which may have perpetuated the high wages.
A low ratio of workers to land seems to be part of the story. Malthusian forces usually pushed societies away from this. The Black Death provided some respite from high population density. Allen mumbles something about the Black Death’s effects maybe still being important a couple of centuries later. But why was this more true of Britain than of neighboring countries?
Some urbanization was also important, as inventors needed other skilled craftsmen nearby as sources of ideas, tools, and parts. So maybe it took a good deal of luck for Britain to get just the right population density?
Before the 1700s, most countries used wood instead of coal, even when they had an ample supply of coal. Switching to coal required significant redesigns to most systems that burned wood.
Countries such as Britain didn’t recklessly exhaust their supply of wood. Demand for wood in Britain grew due to population growth, and the resulting rise in wood prices would have constrained London’s population growth if it weren’t for increased use of coal. But that was due at least as much to the high cost of transporting fuel over long distances as it was to the limited supply of wood.
Something was fairly unusual about Britain’s best coal mines. They produced unusually cheap coal. That helped Britain switch from wood to coal for heating and machinery, well before other countries did.
That didn’t mean that coal was much cheaper in London than in other major cities. High transportation costs made coal a mediocre option almost anywhere other than right at a mine.
China is a key country to look at when wondering where the industrial revolution could have started. How did China’s cheapest coal mines compare to Britain’s? Allen presents no data. Pomeranz seems to care about the quantity of coal reserves, not the cost of the lowest hanging fruit. Coal use in 1700 seems to have been too small relative to reserves for the quantity of reserves to matter much.
It’s unclear whether anyone knows whether China had locations where coal was as cheap as Britain’s cheapest coal mines.
If China didn’t have cheap coal, how much of that was due to natural conditions, and how much of it was due to less interest in developing cheap coal mines? I’m frustrated at how little I’ve found on this subject. The closest that I’ve found to an answer is this claim from Vries:
My thesis would be that China, in a way, also had its ‘coal’ and its colonies, but that government was a serious hindrance in making the most of them. When it comes to coal mining, the Qing often prohibited opening mines in the first place or wanted those already opened closed down. Initiatives by government itself to open mines or to ‘modernize’ them are absent.
Allen implies that cheap coal is obviously good. I see some tension between that and evidence from the past century concerning the effects of natural resources on economic development. There are enough examples of failing resource-rich countries that economists often refer to a curse of natural resources. The curse appears to mostly depend on large international commodity markets, which didn’t exist for coal until sometime after 1800. So it’s not a strong argument against Allen’s theory. It’s merely a warning that it’s easy to overestimate the benefits of natural resources.
Coal seems like a plausible guess as to why Britain developed key technologies before highly similar societies such as Denmark and the Netherlands. But there were numerous differences between Britain and China. I don’t see a clear argument that coal prices deserve to be treated as one of the top two relevant differences. I’ll guess that, in spite of the “Global” in the book’s title, Allen hasn’t studied China enough to have much insight about why it lagged behind Europe.
Allen gives a detailed description of the development of steam power, as a clear example of where innovation depended on wages being high relative to energy costs. The first steam engines were inefficient enough that they were only worthwhile at coal mines, where they were used to pump water out of the mines. The inefficient use of fuel made it very sensitive to fuel costs.
It took decade of R&D for Newcomen to perfect this underwhelming machine. That much effort could only be repaid where there were many mines that were willing to buy such machines. Britain had far more coal mines than other European countries, partly because the low price of coal led Britain to heat more homes with coal. So Britain was able to afford more R&D.
It took nearly a century of refining steam engines before it made commercial sense for other countries to adopt steam engines.
Why was Britain’s early adoption of the steam engine important? It took a century or so to produce large benefits, at which time other countries copied it.
Was it because the technical knowledge enabled British innovators to be the first to develop better steam engines, and use them in a variety of applications such as railroads, ships, better factories, etc.? Or was the steam engine mainly a symptom of British innovation abilities?
Allen suggests that Britain’s cheap coal and first-mover advantages were more important than cultural or institutional features, at least up to WWI.
The steam engine and cheap iron were dependent on cheap coal, and had important influences on automating factories and transportation. That included a bit of recursive self-improvement: factory automation was used to mass-produce machines used to automate factories.
To the limited extent that Allen identifies a start to the industrial revolution, it was around 1575, when British wages began to diverge from the Malthusian patterns seen in most of Europe and Asia (it took at least another century before British wages exceeded Amsterdam wages).
Allen says cheap coal was around well before then, and doesn’t suggest any other resource-based explanation of what changed in the 1500s to break northwestern Europe out of the Malthusian pattern.
Was it due to lingering effects of the Black Death? Wages certainly increased in the 1300s relative to natural resources, particularly land. That’s a potentially important contributor to high wages two or three centuries later.
But why was that effect stronger and more lasting in Britain than in other parts of Europe? Allen’s coal-related explanation is somewhat plausible from the early 1700s to about 1900. But why did wages stay somewhat above Malthusian levels in the 1600s in northwestern Europe? I’m unclear as to whether Allen thinks he has an answer. I think he attributes it to increased agricultural productivity, driven by growing cities. But I don’t see how those cities provided more of a force in Britain than in the rest of Europe and Asia.
It is now time to compare Allen’s ideas with those of my current favorite book on this topic: Henrich’s The WEIRDest People.
Henrich promotes a clear answer of why the 1500s were special: the rise of Protestant culture.
Allen downplays cultural explanations, enough that I got 90% of the way through the book before realizing that he admits culture played a nontrivial role in the industrial revolution.
Early in the book, he points to versions of cultural arguments that I agree are weak enough to be dismissed. Those versions were probably somewhat popular when the book was written (2009), but have been fading since then. Toward the end of the book, Allen more respectfully mentions several better ideas about cultural influences, mostly from Mokyr.
Here are some relevant cultural influences for which Allen provides some evidence, and which Henrich convinced me are more important than Allen admits:
Allen describes Industrial Enlightenment as a process by which the Scientific Revolution influenced industry.
Allen shows that scientific knowledge contributed to some key inventions, such as the steam engine, via better knowledge of the principles by which those inventions worked. But he also argues that other important industries such as cotton advanced without much contribution from scientific knowledge.
The harder-to-evaluate impact of science involves indirect cultural effects. The social networks associated with science may have indirectly influenced innovation, e.g. by encouraging more experimentation in industry.
I’m reminded of this quote from Shut Out:
The evolution of capitalism has led to almost universal acceptance of middle-class values. Whereas the elite of most societies have sought control and leisure, these few modern open access societies have a citizenry that seeks to be productive, to cooperate, and to innovate. It is common to hear complaints that wealthy children today have an unfair advantage because they can access the best schools, get the best education, and therefore perpetuate inequality by working in the most lucrative careers. But everyone should appreciate how revolutionary this is. Elites of the past would scoff at the notion that this even describes elites. Elites don’t need to be productive. Elites have access and control.
Did this change in elite culture begin around 1500? It was certainly far from common for elites to involve themselves in business, but Allen says some important inventors came from elite backgrounds. How much did this differ from other parts of the world?
There are a variety of ways that elite interest in industry might have improved innovation: more spare time and resources to devote to investments that don’t provide quick payoffs, or maybe better cognitive abilities due to better nutrition and/or better genes.
These certainly correlated with the changes that seeded the industrial revolution. Allen expresses doubts about the direction of causality.
Protestant culture has some features which slow population growth. Europe, and especially northwestern Europe, had several cultural norms which prevented early marriage, and left a relatively large number of people unmarried.
Without something like that, it seems hard to explain why low population density persisted long enough after the Black Death for technology to sustain high wages.
Allen reports that innovators depended on learning from mentors. Many cultures have a distrust of strangers that limits such learning to a small circle of people who trust each other because they’ve lived together most of their life.
Protestant culture promoted trust among all Protestants, paving a path to the accumulation of a richer body of trade knowledge. I’m unsure whether Chinese culture had work-arounds which provided adequate substitutes for this source of trust.
Allen notes that Luddites threatened innovation, particularly in the key cotton industry. Most cultures value conformity more than Protestant culture does. I can imagine that no other culture would have produced entrepreneurs who persevered in the face of that kind of opposition.
Henrich, and to a lesser extent Allen, have helped to illustrate the differences between historians and scientists.
Historians focus on building stories about particular, unique, events. Whereas scientists seek general theories whenever possible.
Was the industrial revolution a unique event, or was it a long pattern of related events that might be better explained by a broad theory? Historians seem biased toward the former, scientists toward the latter. Allen seems to be mostly a historian, but has enough economic training to be more neutral on this issue than most authors. Whereas Henrich is mostly trying to be a scientist, and not a historian.
To the extent to which it was a long pattern of events, I value the opinions of scientists who focus on theories about which features of 16th through 18th century Britain caused it to stand out. That would help me predict what countries will become more powerful. So I want to avoid erring in the direction that historians err, more than I want to avoid the opposite mistake.
Here are several considerations that lead me to give more weight to Henrich’s cultural model:
There are many markets today which English-speaking countries dominate in ways that are somewhat hard to explain by coal or high wages: the internet, universities, medicine, movies, etc. That seems to create some presumption in favor of explanations that focus on general-purpose abilities such as culture and institutions.
Allen’s perspective encourages us to imagine that a good deal of British success comes from a first-mover advantage that has been self-sustaining for a couple of centuries. That seems to be somewhat large compared to other historical examples of first-mover advantages or resource-based advantages.
What are the best such examples? Cities built around ports have smaller but longer-lasting advantages, due to natural resources (harbors). I guess that’s a good enough comparison that I can’t say that Allen’s perspective is too far-fetched.
Cultural models provide a clear explanation of the timing of the industrial revolution. I don’t see how resource-based models explain the timing.
Allen says that other countries adopted British technology when it became profitable to do so. Yet that only seems true for countries with cultures similar to Britain’s. Asian countries seem to have adopted it mainly after they imported parts of Western culture.
Allen’s account is the strongest analysis I’ve yet seen of the resource-related forces that contributed to the industrial revolution.
I see almost no conflict between Henrich’s account and Allen’s account about what happened after 1500, only some big disagreements about what was important. They disagree a good deal about what pre-1500 causes were relevant, and they both seem relatively weak there.
Allen emphasizes Britain’s geographic luck, and encourages us to imagine that key inventions were just barely useful enough to create a sustainable take-off. Whereas Henrich attributes northwestern Europe’s luck to cultural choices that were in place by 1520 at the latest, and wants us to believe that take-off was close to inevitable by then. The evidence is weak enough that we may never know which is closer to the truth.
Reading both Allen and Henrich will produce a better understanding than either one of them alone will produce. But if you only read one book, read Henrich’s.
Book review: The WEIRDest People in the World, by Joseph Henrich.
Wow!
Henrich previously wrote one of the best books of the last decade. 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 makes up only about 25% of this book’s focus and value.
Continue ReadingExperts have been debating the causes of the industrial revolution for a long time, with few signs of agreement. I suggest that’s due to a human-centric bias which assumes that no other species could have caused human progress.
I became curious after reading that, while dogs were domesticated, cats intermixed with humans while showing few signs of domestication. Cats have cooperated with humans for long enough that I’d expect at least a little bit of co-evolution. If it wasn’t the humans selecting for the most docile or friendly cats, then maybe it was the cats selecting for the most docile or friendly humans.
One interesting hint is that various human cultures tell different stories about how many lives a cat has. As far as I can tell, the cultures that were most advanced in the 18th century (Britain, China) say cats have 9 lives, the more southern parts of Europe say 7, and Arab cultures say 6. That’s a fairly striking correlation between how highly cultures think of cats and how prospurrous they were near the start of the industrial revolution.[1]
The hardest aspect of explaining the industrial revolution is explaining why the China’s level of development around 1800 didn’t enable it to lead the world. Why did Europe do better than China? Britain seems to have stopped eating cats sometime in the 18th century, while cat-eating has only started to become controversial in southern China this century. I’m less sure what the story is for northern China, where cat-eating apparently doesn’t happen today, but I haven’t found evidence about when cat-eating became unpopular there. Southern China is the region that’s generally said to have been advanced enough that it could have experienced an industrial revolution around 1800. Maybe northern China was backwards then for reasons unrelated to cats, maybe they were held back by their cat-eating southern compatriots, or maybe they adopted a cat-safe culture quite recently – could that have been the change that triggered China’s impressive growth over the past 40 years? Can anyone point me to better evidence on this topic?
Another possible reason for China’s lag is that a completely different species of cat (the leopard cat, Prionailurus bengalensis) acted as “pets” in China about 5000 years ago. Felis catus may have pawsed their human domestication plans in China due to distractions from their struggles with the leopard cat.
I can imagine many strategies that the cats could have used to purr-suade humans to change:
What benefits would the cats have been selecting for?
I presume an important part of their plan would have been selecting for a wider moral circle, since that would make humans safer for cats to live near.
A wider moral circle is correlated with higher trust, and lower violence. These are likely important for cooperation among groups that are much larger than the Dunbar number. See Fukuyama for more on why that mattered.
So, regardless of whether cats planned to advance human civilization, or were merely protecting themselves, their interests in domesticating humans helped generate conditions that were conducive to an industrial revolution.
[1] – A more exotic version of this story is that we’re living in a simulation, and cats are the avatars of the beings who run the simulation. They’re arrogant enough to taunt us by reusing the same avatar just enough for humans to suspect something, but they stop before leaving enough evidence for anything to be proven.
[2] – I don’t want to express any opinion here about the nature-nurture debate, since there are many ways in which cats could have changed human behavior, and I have little hope of tracking down enough evidence to show which strategies the cats actually used. Feline influence on mating could achieve its results via genetic selection – that would require unusual patience, but produce the most stable results. Or the cats could have focused on making the good humans higher status, and the bad humans lower status – that could potentially produce faster results, but is more likely to depend on continuing feline manipulations of human culture.
See also the book A Farewell to Alms for a more detailed argument that British society has long been subjected to selection pressure which made it ripe for the industrial revolution. Alas, it neglects cats.
Book review: The Causes of War and the Spread of Peace: But Will War Rebound?, by Azar Gat.
This book provides a good synthesis of the best ideas about why wars happen.
It overlaps a good deal with Pinker’s The Better Angels of Our Nature. Pinker provides much more detailed evidence, but Gat has a much better understanding than Pinker of the theories behind the trends.
Continue Reading
Book review: State, Economy, and the Great Divergence: Great Britain and China, 1680s – 1850s, by Peer Vries.
Yet another book on why Britain and China diverged dramatically starting around 1800. This one focuses on documenting the differences between the regions, with relatively little theorizing.
Some interesting differences of possible relevance to the divergence:
Book review: Political Order and Political Decay, by Francis Fukuyama.
This book describes the rise of modern nation-states, from the French revolution to the present.
Fukuyama focuses on three features that influence national success: state (effective bureaucracy), rule of law, and autonomy (democratic accountability).
Much of the book argues against libertarian ideas from a fairly centrist perspective, although he mostly avoids directly discussing libertarian beliefs. Instead, he implies that we should de-emphasize debates over big government versus small government, and look more at effectiveness versus corruption (i.e. we should pull sideways).
Many of these ideas build on what Fukuyama wrote in Trust – I suggest reading that book first.
War! What Is It Good For?. Fukuyama believes that war sometimes causes states to make their bureaucracy more efficient. Fukuyama is more credible here than Morris because Fukuyama is more cautious about the effects he claims to see.
The book suggests that young nations have some key stage where threat of conquest can create the right incentives for developing an efficient bureaucracy (i.e. without efficient support for the military, including effective taxation, they get absorbed into a state that does better at those tasks). Without such a threat, states can get stuck in an equilibrium where the bureaucracy simply serves a small number of powerful people. But with such a threat, politicians need to delegate enough authority that the bureaucracy develops some independence, which enables it to care about broader notions of national welfare. (Fukuyama talks as if the bureaucracies are somewhat altruistic. I think of it more as the bureaucracies caring about their long-term revenue source, when individual politicians don’t hold power long enough to care about the long term).
It seems plausible that China would have helped to lead the industrial revolution if it had faced a serious risk of being conquered in the 17th and 18th centuries. China’s relative safety back then seems to have left it complacent and stagnant.
Fukuyama hints that the three pillars of modern nation-states (state, law, autonomy) have roughly equal importance.
Yet I don’t buy that. I expect that whatever virtues are responsible for the rule of law are a good deal more important than effective bureaucracies or democratic accountability.
Fukuyama doesn’t make a strong case for the value of democracy for national success, presumably in part because he expects most readers to already agree with him about that. I’ll conjecture that democracy is mostly a byproduct of success at the other features that Fukuyama considers important.
It’s likely that democracy is somewhat valuable for generating fairness, but that has limited relevance to what Fukuyama tries to explain (i.e. mainly power and wealth).
Full-fledged rule of law might be needed to get all the benefits of the best modern societies. But the differences between good and bad nations seems to have originated well before those nations had more than a rudimentary version of rule of law.
That suggests some underlying factor that matters – maybe just the basic notion of law as something separate from individual leaders or ethnic groups (Fukuyama’s previous book says Christianity played an important role here); or maybe the kind of cultural advance suggested by Greg Clark.
Fukuyama argues that it’s risky to adopt democracy before creating effective states and the rule of law. He’s probably right to expect that such democracies will be dominated by people who fight to get the spoils of politics for their family / clan / ethnic group, with little thought to national wellbeing.
National identity is important for producing the kind of government that Fukuyama likes. It’s hard for government employees to focus on the welfare of the nation if they identify mainly as members of a non-majority ethnic group.
He mentions that the printing press helped create national identities out of more fragmented cultures. This seems important enough to Europe’s success that it deserves more emphasis than the two paragraphs he devotes to it.
He describes several countries that started out as a patchwork of ethnic groups, and had differing degrees of success at developing a unified national identity: Tanzania, Kenya, Nigeria, and Indonesia. I was a bit disappointed that the differences there seemed to be mostly accidents of the personalities of leading politicians.
He talks as if the only two options for such regions were to develop a clear national identity or be crippled by ethnic conflict. Why not also consider the option of splitting into smaller political units that can aim to become city-states such as Singapore and Dubai?
He makes many minor claims that sound suspicious enough for me to have moderate doubts about trusting his scholarship.
For example, he tries to refute claims that “industrial policy never works”, mainly by using the example of the government developing the internet. (His use of the word “never” suggests that he’s not exactly attacking the most sophisticated version of the belief in question). How familiar is he with the history of the internet? The entities in charge of internet tried to restrict commercial use until 1995. Actual commercial use of the internet started before the government made a clear decision to tolerate such use, much less endorse it. So Fukuyama either has a faulty understanding of internet history, or is using the phrase industrial policy in a way that puzzles me.
Then there’s the claim that the Spanish conquered important parts of the New World before the native nations had declined due to European diseases. Fukuyama seems unfamiliar with the contrary evidence reported by Charles C. Mann in 1491 and 1493. Mann may not be an ideal source, but he appears at least as reliable as the sources that Fukuyama cites.
That leads into more general doubts about history books, especially ambitiously broad books aimed at popular audiences.
Tetlock’s research into the accuracy of political pundits has led me to assume that a broad range of “expert” commentary is roughly equivalent to random guessing. Much of what historians do [1] seems quite similar to the opinions of the experts that Tetlock studies. Neither historians nor political pundits get adequate feedback about mistaken beliefs, or get significant rewards for insights that are later confirmed by new evidence. That leads me to worry that the study of history is little better than voodoo.
In sum, I can’t quite decide whether to recommend that you read this book.
[1] – I.e. drawing inferences from aggregations of data. That’s not to say that historians don’t devote lots of time to reporting observed facts. But most of those facts don’t have value to me unless I can generalize from them in ways that help me understand the future. Historian’s choices of what facts to emphasize will unavoidably influence any generalizations I draw.
Book review: Foragers, Farmers, and Fossil Fuels: How Human Values Evolve, by Ian Morris.
This book gives the impression that Morris had a halfway decent book in mind, but forgot to write down important parts of it.
He devotes large (possibly excessive) parts of the book to describing worldwide changes in what people value that correlate with the shifts to farming and then industry.
He convinces me that there’s some sort of connection between those values and how much energy per capita each society is able to use. He probably has a clue or two what that connection is, but the book failed to enlighten me about the connection.
He repeatedly claims that each age gets the thought that it needs. I find that about as reasonable as claiming that the widespread malnutrition associated with farming was what farming cultures needed. Indeed, his description of how farming caused gender inequality focuses on increased ability of men to inflict pain on women, and on increased incentives to do so. That sounds like a society made worse off, not getting what it needs.
He mentions (almost as an afterthought) some moderately interesting models of what caused specific changes in values as a result of the agricultural revolution.
He does an ok job of explaining the increased support for hierarchy in farming societies as an effect of the community size increasing past the Dunbar Number.
He attributes the reduced support for hierarchy in the industrial world to a need for interchangeable citizens. But he doesn’t document that increased need for interchangeability, and I’m skeptical that any such effect was strong. See The Institutional Revolution for a well thought out alternative model.
I had hoped to find some ideas about how to predict value changes that will result from the next big revolution. But I can’t figure out how to usefully apply his ideas to novel situations.
See also Robin Hanson’s review.
Book review: The Measure of Civilization: How Social Development Decides the Fate of Nations, by Ian Morris.
The ambitious attempt to quantify the sophistication of societies is a partial success.
His goal is to compare the development of the two leading centers of human progress over the past 16000 years (western Eurasia and eastern Asia).
I read this book before looking at summaries of his previous book. The Measure of Civilization was designed to provide support for the claims in the prior book, but was objective enough that I didn’t infer from it what the main message of the prior book was.
When I focus on the numbers in this book and ignore other ideas I’ve read, the most plausible hypothesis I see is that the east followed a more risk-averse strategy than the west. The west suffered at least one crash (200-700 CE) that was a good deal worse than anything the east is known to have experienced.
He tries to measure four different quantities and aggregate them into an index. But the simplest way to scale them leaves two (information use and military power) insignificant until about 1900, then rising at a rate which seems likely to make them the only factors that matter to the index fairly soon. He briefly looks at some better ways to aggregate them, but they still seem inadequate.
In sum, the basic idea behind measuring those four quantities seems sound. If he wasn’t any more arbitrary about it than I suspect, then the book has been somewhat helpful at clarifying the trends over time of the leading human cultures, and maybe added a tiny bit of insight into the differences between east and west.
Book review: Masters of the Word: How Media Shaped History, by William J. Bernstein.
This is a history of the world which sometimes focuses on how technology changed communication, and how those changes affected society.
Instead of carefully documenting a few good ideas, he wanders over a wide variety of topics (including too many descriptions of battles and of individual people).
His claims seem mostly correct, but he often failed to convince me that he has good reason for believing them. E.g. when trying to explain why the Soviet economy was inefficient (haven’t enough books explained that already?) he says the “absence of a meaningful price signal proved especially damaging in the labor market”, but supports that by mentioning peculiarities which aren’t clear signs of damage, then describing some blatant waste that wasn’t clearly connected to labor market problems (and without numbers, doesn’t tell us the magnitude of the problems).
I would have preferred that he devote more effort to evaluating the importance of changes in communication to the downfall of the Soviet Union. He documents increased ability of Soviet citizens to get news from sources that their government didn’t control at roughly the time Soviet power weakened. But it’s not obvious how that drove political change. It seems to me that there was an important decrease in the ruthlessness of Soviet rulers that isn’t well explained by communication changes.
I liked his description of affordable printing presses depended on a number of technological advance, suggesting that printing could not easily have arisen at other times or places.
The claim I found most interesting was that the switch from reading aloud to reading silently and the related ability to write alone (as opposed to needed a speaker and a scribe) made it easier to spread seditious and sexual writings due to increased privacy.
Bernstein is optimistic that improved communication technology will have good political effects in the future. I partly agree, but I see more risks than he does (e.g. his like of the democratic features of the Arab Spring aren’t balanced by much concern over the risks of revolutionary violence).