How Cosplaying Ancient Rome Led, Slowly, to Science: Ada Palmer on Renaissance Florence, Gutenberg, and Censorship

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Overview

Ada Palmer is a Renaissance historian, novelist, and composer at the University of Chicago and the author of Inventing the Renaissance. In this conversation with Dwarkesh Patel she lays out a long chain of events. Fourteenth-century Italians tried to revive Roman virtue by rebuilding Roman libraries. That project failed on its own terms, and the failure was then reinterpreted, first by Machiavelli and later by Bacon and Galileo, into new ways of using knowledge. Along the way she describes Florence's odd merchant republic and how the Medici captured it, why Gutenberg went broke, how writing surfaces shaped what survived from antiquity, and why censors in every era worry about the wrong things. Her recurring theme is that historical change has more steps than the usual story admits, and that people who try to steer history rarely get the outcome they intended.

39 min read

Why the republics clustered in Italy

Patel opened by asking why Venice, Florence, Genoa and other republics were concentrated in Italy. Palmer traced it to the collapse of Roman authority in the West. With no central government to guard roads, suppress bandits, or maintain supply routes, every city had to govern and feed itself. Large, wealthy towns surrounded by good farmland could manage this. They could set up a senate on the Roman model and have their leading families rule as a council.

Weaker towns fared differently. A single wealthy family might hire enforcers and declare itself monarch. Or a town that could not feed itself emptied out: frightened residents moved next to a noble family's fortified villa and worked for the family in exchange for protection. Palmer describes the village, "a villa and its environs," as a monarchical structure in this sense. Because Italy had unusually good agricultural land, she argues, more of its cities could sustain themselves as towns, and so more of them could be republics.

Petrarch's project: raise better rulers by reading what the Romans read

Palmer's account of the Renaissance begins with Petrarch, who survived the Black Death in an Italy torn by civil war, foreign mercenaries, and bandits. She gives one example. After the plague, Petrarch learned that two younger scholar friends had survived and were coming to visit. On the way bandits attacked them. One was killed, and the other was wounded and lost in the mountains, and Petrarch did not learn he was alive for another year and a half.

Petrarch called his time an age of ash and shadow and blamed selfish leaders who put wealth, family honor, and power ahead of their people. Palmer uses Romeo and Juliet to illustrate. Montague and Capulet care about beating each other, not about Verona. Their feud harms the city, and they expect Romeo to escape punishment for murder because he is their son. Against this Petrarch set Livy's account of the early consul Brutus, the ancestor the later Brutus tried to live up to, who executed his own sons for plotting to make him king. Nobody could imagine Montague executing Romeo for treason against Verona.

Petrarch's proposed remedy was educational. If young Cicero and young Brutus read Plato and Homer, then recreating that reading environment might produce leaders like them. His successors spent heavily on crossing the Alps to hunt for manuscripts and on buying books in Constantinople, where books were far more common. They built libraries and trained tutors such as Marsilio Ficino to surround young princes and princesses with classical values. Palmer notes that this rested on an assumption that education works by osmosis: expose people to something and they will imitate it.

The propaganda payoff: an ambassador in Cosimo's courtyard

The idea caught on quickly, Palmer says, for a less idealistic reason. Italy was full of upstart rulers who had just seized power by coup and had no legitimacy. They could dress as Roman emperors, stage parades with allegorical Virtues, and build palaces with pediments so they looked like the Caesars rather than like tyrants. The Medici needed this even more. They were merchants, and not even among Florence's leading families. In Palmer's words they were "three ranks down."

She describes a scene to show how this worked. A French nobleman is traveling to Rome to deliver the ceremonial oration every country owed a newly elected pope. He passes through Florence expecting nothing worth his time. Florence was a merchant town with no nobility and a reputation as Europe's capital of sodomy; Palmer says "to Florentine" was a verb for anal sex in several languages, and French law treated having ever visited Florence as sufficient evidence for a sodomy indictment. Then he sees lifelike new statues, a dome larger than anything except Roman ruins, and a banker's palace whose airy courtyard looks like the ruins behind the castle where he grew up. There are busts of every emperor in order, a gleaming bronze statue that hasn't yet turned green, and men in ancient-style robes speaking Greek, a language he believes is lost. The banker has Plato, whom he also believes lost. His ten-year-old grandson Lorenzo then recites his own Greek poem on the three parts of the soul. At that point Cosimo de' Medici asks whether the ambassador would like an alliance.

The ambassador could refuse. His king could invade and sack a city that has no noble marriages, no allies, and hostile neighbors caught in the Guelph–Ghibelline feud. Or he could agree and ask for a bronzesmith, an architect, a Greek teacher, and a Platonist to take home, so that the next Portuguese ambassador would feel as uncultured as he does now. Palmer's point is that the condescending nobleman ends up in awe of the merchant. That reversal is what art and culture did as propaganda.

The plan fails, and Machiavelli reinterprets it

The generation raised as "philosopher princes" did not produce a golden age. Palmer says they fought bigger and nastier wars than before, with more betrayal and bigger cannons, and with more mercenaries because wealth had become more concentrated. Cesare and Lucrezia Borgia both had Latin, Greek, Cicero, and Plato as children, and Cesare, in her phrase, "sets fire to half the world."

Machiavelli watched those wars. He was raised in the Petrarchan tradition and loved it, and Palmer cites his letter from exile describing how he wasted his day hunting larks and drinking with countrymen, then put on his old court robes to enter his library and "hold commerce with the ancients." But he also saw Guidobaldo da Montefeltro, who did everything virtuously and had the libraries and the art, get betrayed and lose his state, while Cesare Borgia and Julius II made terrible choices and succeeded. Palmer's reading is that Machiavelli concluded Petrarch was wrong that reading Cicero produces good rulers, while still believing the classics held great power. His answer was to use them differently: treat history as a casebook. Line up five battles fought beside rivers, compare the commanders' decisions, and imitate what worked. She says this is part of why contemporaries described him as a historian, and that his approach took decades to catch on.

Palmer stresses how long this took. From Petrarch's call to Machiavelli's writing is about as long as from Napoleon's childhood to Yuri Gagarin's spaceflight, and at that point Shakespeare's grandparents had barely been born. Meanwhile, book technology kept improving. Ficino's generation needed masterful Latin to read the ancients because there were no dictionaries or glosses. A century later there were vernacular translations and marginal notes explaining hard vocabulary. When Poggio rediscovered Lucretius, Palmer estimates two dozen people could read it; a century later perhaps 30,000 could, across roughly 30 printed editions before 1600. Medical students, law students, and readers in many countries asked new questions and tested hypotheses. That generation, she says, discovered the heart is a pump and seriously considered whether atoms might explain disease, in the 1560s–1580s, about 160 years after Lucretius resurfaced. By around 1600, Bacon and Galileo proposed treating nature as a casebook the way Machiavelli had treated history.

Why this story, and not the other twenty?

Patel pushed back. There are many causal stories for the Scientific and Industrial Revolutions, for example Joseph Henrich's argument that the Church broke down kinship networks and encouraged guilds. Why favor this one?

Palmer gave two answers. First, new ideas need a fertile environment, like topsoil for a forest: enough books, and networks moving information among enough readers. You can't publish a scientific journal before journals exist. She argued that people often reverse the causation, assuming literacy creates books when it is often the other way around. She said Florence had roughly 90% male literacy as early as the twelfth century, because merchants needed to write letters and read account books. But very few of those people had read a book, since a city in 1200 or even 1500 might hold almost none. She compared this to the difference between watching television and watching films. By 1600 any medium-sized town had books. She said guilds were also generators of ideas and by 1600 had libraries on their own trades, which would not have been true in 1100. All these factors, she said, are real and parallel.

Second, she said her focus is showing that there are more steps than we think. "They rediscovered ancient texts and then we got science" is true but zoomed out too far, like saying Napoleon spread nationalized warfare and then we landed on the moon.

Patel connected this to AI, where many people believe doing some particular thing will make it go well, even though nobody has a good track record of steering large unanticipated changes. Palmer drew a distinction between "go my way" and "go well." Petrarch expected the ancients to agree with Christianity, needing only "a little shaker of the Trinity on top." He was guessing, since the books hadn't been found yet. What turned up was a quarrelsome plurality of Epicureans, Stoics, and others. That led to wars, Machiavelli's critique, the new science, and eventually Voltaire and Montesquieu promoting smallpox inoculation, then germ theory, hygiene, vaccines, and penicillin, which treats the plague. A time-traveling Petrarch, she says, would be horrified by democracy, since he thought only a tiny elite could rule, but would weep for joy that the Black Death is curable. He did not get the world he wanted, but it went well. Her other example is trains and bicycles, which made it easier for women to move independently and organize, contributing to the suffragette movement, something the inventor of the train never intended.

Florence's weird republic

Palmer explained how Florence differed from other republics. Venice, Genoa, Bologna, Siena, and the Swiss followed an oligarchic Roman model: hereditary senatorial families from whom consuls or heads of state were chosen, ruling over a commoner majority.

Florence was like that until it concluded that threats to republics usually came from nobles, who were the military class; no soldier would follow a commander without noble blood. After a near takeover, Florence massacred most of its nobility, burned their houses, and "raked salt into the earth." A few well-liked noble families were allowed to formally renounce their status and change their names. What remained was a commoner republic governed by members of merchant guilds, meaning owners of workshops and firms rather than the workers in them. Palmer calls "bourgeoisie" anachronistic but apt.

This created practical problems. In every other polity, rulers and ambassadors were noble, so to outsiders Florence's rulers ranked as valets. Florence couldn't lead its own armies or police, because nobody would surrender to a man without a coat of arms. So it hired a noble podestà to arrest people in the Holy Roman Emperor's name. He lived in the palace, which was also the prison. At the end of his term he was paid well, escorted to the gates, and banished for life on pain of death so he couldn't use his position to seize power.

Rule itself was by sortition. Guild members judged fit to serve, meaning not dying, not insane, and not so indebted that creditors could manipulate them, had their names placed in a bag. Nine were drawn at random, locked in the government tower for two or three months so they couldn't be bribed or kidnapped, and then replaced. Decisions required consensus of all nine, not a majority, which was meant to make the system tyrant-proof.

Asked why merchants had such status, Palmer pointed to the patronage system, which she says existed in ancient Rome and ran through medieval and Renaissance society. Employers, not the state, were the safety net. They cared for the orphans of employees who died, supported and found suitable work for the disabled, and supplied defense lawyers and persuasive notes to judges. If a brewer's son killed someone in a bar fight, the brewer went to his landlord, who went to his landlord, up to one of the great families that owned dozens of apartments and employed hundreds or thousands. A council of these "CEOs" felt like real representation to people. Palmer adds that the society was used to hierarchy and had no confidence in democracy. When Machiavelli praises the popolo, meaning the people who should be respected and armed, nineteenth-century readers heard something like America's founding documents. But the popolo was the top 4% or so economically, the guild members.

How the Medici captured the lottery

Palmer explained the Medici's power through their role as papal bankers. In a world without wire transfers, taxes were collected by chains of local agents, each passing a set amount upward and keeping the rest, which is why tax collectors had a reputation for wickedness. As papal banker, Cosimo channeled money from every church collection box and pilgrim offering in Christendom, taking a cut before passing it to the papacy. That produced enormous cash flow and a huge network of contacts.

Sortition, which Palmer notes Athens used and which she says works well, can be corrupted like any system. Cosimo's first method was simple statistics. If a third of the city is on your payroll, about three of any nine drawn names will be your people. Give them your policies and tell them to send for you with questions, and in a body with no majority faction your plurality controls it. But chance cuts both ways. In the early 1430s, Palmer says, a draw produced men hostile to Cosimo, who declared him a traitor and locked him in the tower. He bribed his way out, with the equivalent of about $300,000 to the guard and $700,000 to the captain. He later wrote that they were the two most foolish men he had ever met, because he would happily have paid tens of millions. The next draw favored him. He was welcomed back as father of the fatherland, and his enemies turned out to be guilty of tax evasion and more. After that he bribed the people who ran the draws. Palmer quotes his line: "It is dangerous to be rich and not powerful."

Monarchs who knew they were weak

Even after the Medici became dukes, Palmer argues, Florentines were so attached to their republic that the rulers had to maintain its forms: named offices, important guilds, and the mandatory office garment, the lucco fiorentino, which Palmer had in the room. To us it looks like a long red Renaissance robe; to them its draping made it a toga, "cosplaying the Roman Republic." Cosimo I, the first duke, wore one to costume balls. Patel noted the double irony that imperial Rome also kept its Senate, which Palmer said met until around 1200 AD.

Her favorite illustration is the Vasari Corridor, the elevated walkway the dukes built from the old city palace over the Ponte Vecchio to their larger new palace, so they could cross the city without being assassinated. She calls that a sign of a weak duke. The corridor cut through the upper floors of houses along the way, and most owners complied, with heads of resisters still rotting on spikes outside the Palazzo Vecchio. But the Mannelli family, who trace their lineage to Roman times, refused to let him cut the top off their 500-year-old tower. The duke gave in, and the corridor detours awkwardly around it. Palmer argues he knew that violating long-held property rights would provoke rebellion. By contrast, she describes Duke Alfonso I d'Este of Ferrara wandering the city naked with a sword to show no one would dare harm him, and his siblings kidnapping each other's musicians and killing each other's servants for fun.

Her conclusion is that Florence's republic lost, but because people fought hard for it, its tyrants were much less tyrannical: "even when resistance loses, resistance wins." Patel offered a parallel. He thinks the odds of America becoming Putin-style within a couple of decades are low because republican expectations are strong and resistance discourages further escalation. Palmer replied that what weakens American resistance is treating partial victory as failure, and that the Florentine example shows partial victory mattering for centuries.

Machiavelli in exile, and what The Prince was for

Machiavelli's family had served the Medici for generations. Palmer says he was never fully enfranchised himself, because his grandfather's unpaid tax debt barred him from the lotteried offices. She reads his lifelong service as real patriotism: even people excluded from the 5% valued being ruled by them rather than by one man, "an inch more liberty than monarchy." A young, weak Medici heir botched diplomacy during the French invasion and was expelled, and Machiavelli served the restored republic. When the Medici returned, his name was found on a resistance group's list of potential recruits. He had not organized anything, but he was arrested, tortured, and exiled, and in exile wrote The Prince, dedicated to the family that exiled him.

Palmer explains that Florence used exile as part of its diplomacy. With no nobles to serve as ambassadors, it posted exiles to Bruges or London as informants and letter-forwarders, with return as the reward for good conduct. Machiavelli instead was told to sit in a Tuscan hamlet "and rot." Everyone expected him to leave for a cardinal's household or a court in Milan, Naples, or England, as other exiled Florentine intellectuals such as Francesco Filelfo did. He stayed and kept writing that he would serve his city or nothing.

Asked how we know this wasn't just a bid to return to power, Palmer pointed to his private letters. He published his comic play and his history of Florence, but circulated The Prince only among close friends and to Florence itself. She calls it a job application whose message is loyalty to the city regardless of regime. On the ruthless advice, she argues the end justifies the means only when the end is the country's survival. Having seen Florence's streets run with blood, he believed regime change brings civil violence and possibly foreign conquest, and that more people survive under a tyrant than through another upheaval.

Why Gutenberg went broke

Patel asked how Gutenberg and then his apprentices went bankrupt when men like Cosimo paid what Palmer's book equates to hundreds of thousands of dollars per book. Her answer: printed books were a mass-produced commodity in a world without distribution networks for mass-produced goods. Coins were about the only other example. She compares this to e-books, which technically existed decades before the Kindle created a market for them.

Gutenberg could make 300 Bibles for the cost of one, but in his small landlocked town only about seven people, the priests, were allowed to read the Bible. Three hundred buyers existed across Europe, but not in one place. He went bankrupt. The bank that seized his press went bankrupt. Palmer says he had borrowed roughly $1.5 million in today's terms, largely for paper, which had to be bought in bulk up front so the color matched throughout a book. His apprentices went bankrupt too, fled their debts, and ended up in Venice. Venice was the Mediterranean's transfer hub: a printer could give ten Bibles each to thirty captains bound for thirty cities. That, Palmer says, was the first economically sustainable circulation of print. Book fairs followed, where printers traded a thousand copies of one title for five copies each of two hundred. The Frankfurt Book Fair still exists.

Printers also discovered pamphlets. One press would spend six months on a valuable book while another turned out a five-page report in a couple of days, such as what everyone wore at a royal wedding, for immediate sale.

One information revolution, not many

Palmer argues that the computer, the personal computer, the internet, cell phones, social media, and now LLMs and generative AI are not separate revolutions but deeper penetration of one: computing. Print worked the same way. It arrived around 1450, took about forty years to become profitable in the 1490s, produced pamphlet news around the 1510s (which she compares in scale to the shift from computers to cell phones), enabled the Reformation the way cell phones enabled the Arab Spring, and later produced the newspaper, which she compares to social media. Print kept hitting Europe with successive shocks for about 150 years. When a pamphlet could get from Wittenberg to London in seventeen days, a coordinated anti-Catholic movement became possible, which had not been true a decade earlier.

Has history sped up?

Patel noted how fast events seemed to move in the period, with people in 1506 nostalgic for 1490. Palmer said history has always moved that fast. High school teaching compresses long stretches and invents periods of stagnation, but zoom in anywhere and every decade feels different; people in the 1320s were nostalgic for the 1300s. She blames nineteenth-century histories that tried to make modernity special. She is writing a paper on Civilization, which she calls the world's number one history teacher since 1991, with 70 million copies shipped. In the game a turn is fifty years in antiquity and shrinks to one year in modernity. Palmer says our textbooks repeat that same lie.

When Patel said the difference is that technology wasn't moving as fast, she disagreed. It was; we just no longer care about those technologies: chairs with backs, scissors, better steel. She cited a book she is reading on why Raphael's and Michelangelo's colors glow like gemstones compared with paintings a century earlier. The answer is about eleven technical advances over 120 years in processing oil and pigments, spreading through the fake-gemstone industry and then through frame-makers who faked gold by painting yellow over tinfoil, before artists adopted the techniques.

Patel pressed that fourteenth-century people themselves saw Rome as the peak, whereas we obviously see progress since them. Palmer acknowledged that population growth matters. She said most humans who ever lived have lived in the last 200 years, because agriculture and hygiene allowed it, and that systematic science after 1600 introduced a deliberate social push for progress.

Leonardo as saboteur, and Bacon's honeybee

To provoke her students, Palmer tells them Leonardo da Vinci was not a scientist. By her definition, a scientist publishes results for others to test so everyone's knowledge advances. Leonardo wrote in mirror-script code and kept his methods even from his assistants, because he wanted to make unique masterpieces that later generations would marvel at the way he marveled at the Pantheon. Brunelleschi burned his notes and plans for Florence's dome so no one could replicate it. Palmer calls such figures inventors and engineers, but as far as a scientific community goes, "a saboteur of human progress." That, she says, was normal for learned inventors in the 1400s and 1500s.

Around 1600 the ideal changed, and she uses Francis Bacon's image of three insects. The ant is the encyclopedist who piles up knowledge and sits on it. The spider spins beautiful theoretical webs from its own body with nothing real in them. The honeybee gathers from nature and turns it into something sweet and useful for humankind. With Bacon's portrait on its title page, England's scientific academy began publishing, and the measure of achievement shifted from building the dome to explaining how and sharing it. Bacon promised better agriculture, fewer famines, refrigeration, "chicken in winter," and called science the ultimate charity, a gift to everyone who will ever live. In the 1620s–30s, with Galileo publishing observations, Descartes publishing systems, the heart revealed as a pump, and magnification showing patterns on a flea's wing, it felt like the start of progress.

Palmer says progress had in fact been continuous: plows, seed, larger cabbages, better pots. Bacon himself saw it while working in the patent office, where artisans brought in improved chisels. People in 1630 believed history had been stagnant; in her view they were really recognizing and naming an acceleration already under way. On the hockey-stick graph, she thinks humanity would have hockey-sticked eventually even without systematized science, "probably a bit later," with a flatter curve and perhaps more pain, the way mice on a mouse-free island multiply and then starve. So did everything accelerate after 1620? In one sense yes; in another it continued a curve already bending upward.

Why Italy didn't industrialize

Patel raised a question from Guido Ruggiero's The Renaissance in Italy: Italy had fine metalworking for type, advanced mills, and clockwork gears, so why no Industrial Revolution? Palmer's main answer is that Italy was already much richer per square meter than anywhere else. It was a breadbasket and the center of "Big Oil," meaning olive oil for lighting, industry, and food, as well as "Big Wool" and "Big Finance." England, lacking olive oil, exported crude wool to Florence for finishing; she explains that a wool suit isn't itchy because of the oil used in processing, at least with pre-modern technology. A place already on top has less reason to industrialize. She added other factors: Italian land was worth more as farmland than as mines; fragmented city-states couldn't legislate large transformations the way England's centralized crown could; and no city wants the industrialization, which is why English industry grew in second-tier towns. When Patel suggested competition between cities should have forced adoption of better textile machines, Palmer said, while admitting it won't sound plausible, that documents she has recently been examining largely confirm Italians figured out industrial looms in the 1400s and chose not to use them, preferring luxurious artisanal fabric. Patel linked this to early printed books imitating handwritten scripts and leaving blanks for illumination so they looked as luxurious as manuscripts.

Papyrus, parchment, and paper: what really destroyed ancient books

Asked whether cheaper paper changed record-keeping, Palmer went back to the fall of Rome. Papyrus was antiquity's cheap writing surface: slice the reed into strips, lay two perpendicular layers in the sun, and they stick together with almost no labor. It made Roman bureaucracy and ordinary city libraries possible, and when Egypt cut off exports during wars, Palmer says Roman administration collapsed overnight. But papyrus dies in frost and in Italy grows only in the far south, in Sicily. Northern and western Europe were left with parchment, "a dead sheep." Her comparison: papyrus is a head of lettuce and parchment is a leather jacket. A handwritten book cost as much as a house, a pocket copy as much as a studio condo, an illuminated Bible as much as a country villa. The University of Paris library, the great library from Europe's point of view, held about six hundred books, fewer than an airport kiosk. Meanwhile, she says, sultans had libraries of thousands of books, as did libraries in sub-Saharan Africa and China, because they had cheap writing surfaces. Only Europe wrote on leather.

This leads to one of her larger claims. Most ancient knowledge was not lost when the Library of Alexandria burned but between about 400 and 600 AD, as brittle papyri crumbled and Europe could afford to recopy only a fraction onto parchment. A monk with a thousand decaying books and resources for a hundred would pick Saint Augustine, which is why, she says, more of Augustine survives than all pagan classical Latin combined. The tastes of whoever held power then acted as unintentional censorship.

Paper reached Europe around 800, "a four-hundred-year famine" after papyrus. It is made from rags beaten to pulp in a mill and lifted on a screen. It cost roughly ten times papyrus but a tenth of parchment; in Palmer's analogy it is a dozen frozen prepackaged meals. Europeans distrusted it. It was used for drafts, letters, and sketches, and she says four hundred years passed before the first state document was written on paper; it was trusted by about 1200. Even in the 1490s wealthy patrons such as Isabella d'Este ordered their copies printed on vellum. Parchment use lasted into the 1700s and 1800s. British Parliament used it for records until about ten years ago, and the Vatican still does.

Palmer then showed objects. There was a hand-stitched pamphlet with a cheap blue cover, whose blue-gray is the color of laundry lint because unbleached rag paper is essentially laundry lint, "the average color of what human beings wear." Her favorite pamphlet title concerns a Paduan doctor who seduced his maid, murdered his wife and the maid, ate the maid's heart, and was "justly punished by God." She showed an 18th-century Gentleman's Magazine with a fold-out of what everyone wore at a state funeral, a papyrus sheet showing its plaid of crossed strips (brittle enough that it works better as a scroll than a folded codex), a 17th-century parchment letter in tiny, nearly illegible handwriting, and pages from a French book of hours of about 1480, written around a hole in the skin because the sheet was too valuable to waste. She described the book of hours as the most common medieval manuscript and "the smartphone of the period," with margins for addresses, friends' notes, and even celebrities' signatures.

She also traced a chain of media, each answering the problems of the one before. Printers made pamphlets to earn money while books were in production. Newspapers answered the problem of not knowing which pamphlets to trust, because a weekly serial has a reputation to protect. The Gentleman's Magazine, which she says gave "magazine" its meaning in this sense, answered contradictory newspapers by comparing each week's reports and judging who was right: an early form of fact-checking.

Inventions arrive when they are needed

Patel's favorite example of slow diffusion is oil, from his interview with Daniel Yergin. Oil struck in 1860s Pennsylvania was used mostly for kerosene lighting, with gasoline thrown away, until mass-produced cars arrived, and the light bulb raised fears that Standard Oil would go bankrupt. Palmer added Julius Caesar's remark that Britons were too poor to burn wood so they burned rocks, which was coal, known long before its industrial use. Her broader point is that societies industrialize when they feel the need. Gutenberg was not a random genius. A boom in library building from the 1410s had spiked demand for books, people were already making smaller books and using more paper, and "we were going to get the invention."

Luther's timing and why pamphlets couldn't be censored

Patel noted her argument that Luther arrived at the right moment: Savonarola in the 1490s was too early. Palmer explained that Savonarola's pamphlets reached only Florence, Siena, and Pisa and took months to travel further, so his movement was crushed. Luther's Ninety-five Theses were in print in London seventeen days after their release in Wittenberg. (Machiavelli, a contemporary of Luther, deliberately kept his work private.)

Censorship regimes followed and were effective at shaping books, but never kept up with pamphlets. She compares this to how governments can pressure CNN but not random social media users. Printers employed the news runners who moved between cities faster than anyone, so they learned of Inquisition convictions first; Palmer says the Inquisition never succeeded in arresting printers, who had always left town. Of the four factors she says determine whether censorship is possible, she named law and technology in particular, and argued that whatever moves information fastest cannot be censored. When Patel asked why authorities couldn't just punish print shops, as China does, she said they did, but the printer moved on, someone else took over the shop, and pamphlets were anonymous and easy to disown. Exile had a real human cost but didn't stop the flow, just as platforms today say pornography or hate speech are "too fast, too much." She cites Anton Matytsin's The Specter of Skepticism in the Age of Enlightenment, which describes a raid on a clandestine bookshop. The crackdowns were real and frightening but could only restrict circulation, not prevent it.

Reading the same book twenty times

Patel observed that before cheap books, even the rich owned few (Palmer thinks Cosimo's father had about twelve), so readers returned to the same texts again and again. Palmer said this created intimacy, a one-way conversation across time, where you respond to the ancients and the future responds to you. Petrarch spoke of his friend Cicero and felt betrayed when he found letters in which Cicero, grieving his daughter, was petty and quarrelsome about real estate instead of living up to Stoic ideals. If even Cicero couldn't overcome grief's pettiness, Petrarch wondered, was humanity doomed to it? He also said Cicero broke "his heart and his foot": a heavy volume fell on his foot, which became infected and left him bedridden for months.

Why the New World seemed minor

Palmer mentioned a conference a week earlier that confirmed a Vatican document from around 1100 or 1200 (she didn't recall which) acknowledging Vinland, known from the Vikings. Her American students struggle to understand why 1492 didn't feel enormous. Part of her explanation is that the first finds were Caribbean islands and coastline, and the scale wasn't understood; the news sounded like something across the water "maybe as big as the Canary Islands." Another part is that Europe was consumed by immediate crises: France about to invade Italy, Spain dominating the papacy, recent Ottoman incursions into Italy and Hungary. Then Luther hit "like a ton of bricks" before anyone realized the discovery was a continent. The New World also joined a crowd of other discoveries: a much larger sub-Saharan Africa, and later the heart as a pump and a sun-centered cosmos. These were paradigm-shifting questions, but they competed with the French invasion. In her view every decade is absorbed by its own turmoil and misses what matters around it.

Censors are always wrong about what matters

Palmer, whose next nonfiction book is a history of censorship, says a reliable game is noticing that censors always target the wrong things from our point of view. During the French Enlightenment, with Voltaire, Rousseau, the Marquis de Sade, and La Mettrie's materialist atheism circulating, the Inquisition focused on Jansenist treatises about the Trinity. She describes Jansenism as combining "all the grimness of Calvinism" with Roman authoritarian centralization. In the raid Matytsin describes, the officials shrugged at Voltaire, the banned Encyclopédie, Diderot, and Rousseau, and were outraged by the Jansenists. When Rome ordered the Encyclopédie burned, France, whose king and queen loved it (the queen reportedly enjoyed looking up how her silk stockings were made), marched it to the fire and then burned Jansenist treatises instead.

Earlier, a time traveler would tell 1540s inquisitors to watch Machiavelli or Lucretius's De rerum natura, the subject of Palmer's dissertation (she recommends her book's more detailed treatment to readers of Greenblatt's The Swerve). But she says there are inquisitors' letters saying Lucretius wasn't worth censoring because only learned people could read it and they knew the false parts were false. The 1545 Index promised to print "arch-heretics" in capitals. She eagerly turned to M and found Machiavelli in lowercase; the capitalized names were Luther, Calvin, Zwingli, Melanchthon and other Protestant theologians. Contemporaries cared more about whom Prince Charles would marry than about a new continent.

On the Inquisition and science, Palmer puts executions for atheism at about 100. She counts 12 trials of scientists over science, including Galileo and Giordano Bruno. Three ended in conviction, and only Bruno was executed. That compares with hundreds of thousands of cases for "Judaizing," and executions for practicing indigenous religion in colonized territories. Patel added Kepler, who worked as imperial mathematician (effectively astrologer to a general) and was excommunicated for being Lutheran rather than for his planetary laws, and whose mother was tried for witchcraft, also unrelated to science. Palmer's final example is Milton. His Areopagitica argued against England's first systematic censorship, which was driven by fear of Papist plots and a deliberately whipped-up moral panic that she compares to those over comic books and Dungeons & Dragons. He lost. Paradise Lost then passed the censors with a charismatic Satan, a God who comes off "kind of a jackass," and anti-monarchical rhetoric borrowed from revolutionary pamphlets, but they made him change one line about a comet causing events, because astrology would "confuse people's souls."

The Inquisition's laboratory

Finally, Patel asked about a line in the book claiming the Vatican had Europe's most extensive facility in the late seventeenth century. Palmer corrected it: it was the most extensive experimental laboratory, not a library, drawing on Daniele Macuglia's research (published in Italian, and she was unsure about English). After Galileo, she says, inquisitors saw themselves as guardians of accurate information and felt obliged to check the books they were sent to censor. If a book described mechanical experiments, they repeated them. In effect they invented peer review, a second laboratory trying to reproduce the first one's results, and some of them were inquisitors by day and wrote their own scientific treatises at night. "It's not what we expect," Palmer concluded, "but history is never what we expect."