• Stephen Greenblatt
  • February 10, 2021
    Read, recorded or researched
Almost six hundred years ago, a short, genial man took a very old manuscript off a library shelf. With excitement, he saw what he had discovered and ordered it copied. The book was a miraculously surviving copy of an ancient Roman philosophical epic, On the Nature of Things by Lucretius and it changed the course of history. This is that story and it's wonderfully told.

The Best Points

The Swerve: How the Renaissance Began


There is no single explanation for the emergence of the Renaissance and the release of the forces that have shaped our own world. But this book tells a little known but exemplary Renaissance story, the story of Poggio Bracciolini’s recovery of On the Nature of Things.

The recovery has the virtue of being true to the term that we use to gesture toward the cultural shift at the origins of modern life and thought: a re-naissance, a rebirth, of antiquity. One poem by itself was certainly not responsible for an entire intellectual, moral, and social transformation—no single work was, let alone one that for centuries could not without danger be spoken about freely in public. But this particular ancient book, suddenly returning to view, made a difference.


Because what Poggio found - On the Nature of Things - was a beautiful poem of the most dangerous ideas; that the universe functioned without the aid of gods, that religious fear was damaging to human life, and that matter was made up of very small particles in eternal motion. These ideas - written more than 2000 years ago! - fuelled the Renaissance, inspiring Botticelli, shaping the thoughts of Montaigne, Darwin and Einstein.

[Here's Greenblatt discussing Lucretius’s work in more detail] On the Nature of Things struck me as an astonishingly convincing account of the way things actually are. To be sure, I easily grasped that many features of this ancient account now seem absurd. What else would we expect? How accurate will our account of the universe seem two thousand years from now?

Lucretius believed that the sun circled around the earth, and he argued that the sun’s heat and size could hardly be much greater than are perceived by our senses. He thought that worms were spontaneously generated from the wet soil, explained lightning as seeds of fire expelled from hollow clouds, and pictured the earth as a menopausal mother exhausted by the effort of so much breeding.

But at the core of the poem lay key principles of a modern understanding of the world. The stuff of the universe, Lucretius proposed, is an infinite number of atoms moving randomly through space, like dust motes in a sunbeam, colliding, hooking together, forming complex structures, breaking apart again, in a ceaseless process of creation and destruction. There is no escape from this process.  

When you look up at the night sky and, feeling unaccountably moved, marvel at the numberless stars, you are not seeing the handiwork of the gods or a crystalline sphere detached from our transient world. You are seeing the same material world of which you are a part and from whose elements you are made. There is no master plan, no divine architect, no intelligent design.

All things, including the species to which you belong, have evolved over vast stretches of time. The evolution is random, though in the case of living organisms it involves a principle of natural selection. That is, species that are suited to survive and to reproduce successfully endure, at least for a time; those that are not so well suited die off quickly. But nothing—from our own species to the planet on which we live to the sun that lights our days—lasts forever. Only the atoms are immortal.  

In a universe so constituted, Lucretius argued, there is no reason to think that the earth or its inhabitants occupy a central place, no reason to set humans apart from all other animals, no hope of bribing or appeasing the gods, no place for religious fanaticism, no call for ascetic self-denial, no justification for dreams of limitless power or perfect security, no rationale for wars of conquest or self-aggrandizement, no possibility of triumphing over nature, no escape from the constant making and unmaking and remaking of forms.

On the other side of anger at those who either peddled false visions of security or incited irrational fears of death, Lucretius offered a feeling of liberation and the power to stare down what had once seemed so menacing. What human beings can and should do, he wrote, is to conquer their fears, accept the fact that they themselves and all the things they encounter are transitory, and embrace the beauty and the pleasure of the world.

The origin story

It was high time for a prudent, highly trained bureaucrat, almost forty years old, to look out for himself and find some stable means of support. But Poggio did nothing of the kind. Instead, a few months after his return from St. Gall, he left Constance again, this time apparently without companions. His craving to discover and to liberate whatever noble beings were hidden in the prison house had evidently only intensified.

He had no idea what he would find; he only knew that if it was something ancient and written in elegant Latin, then it was worth rescuing at all costs. The ignorant, indolent monks, he was convinced, were locking away traces of a civilization far greater than anything the world had known for more than a thousand years. Of course, all Poggio could hope to find were pieces of parchment, and not even very ancient ones. But for him these were not manuscripts but human voices.

What emerged from the obscurity of the library was not a link in a long chain of texts, one copied from the other, but rather the thing itself, wearing borrowed garments, or even the author himself, wrapped in gravecloths and stumbling into the light.

Books that had fallen out of circulation and were sitting in German libraries were thus transformed into wise men who had died and whose souls had been imprisoned in the underworld; Poggio, the cynical papal secretary in the service of the famously corrupt pope, was viewed by his friends as a culture hero, a magical healer who reassembled and reanimated the torn and mangled body of antiquity.

Thus it was that in January 1417, Poggio found himself once again in a monastic library, probably Fulda. There he took from the shelf a long poem whose author he may have recalled seeing mentioned in Quintilian or in the chronicle compiled by St. Jerome: T. LUCRETI CARI DE RERUM NATURA.

Why it was so dangerous

When the manuscript of On the Nature of Things finally did reach him, Poggio evidently sent it off at once to Niccolò Niccoli, in Florence. Either because the scribe’s copy was crudely made or simply because he wanted a version for himself, Poggio’s friend undertook to transcribe it. This transcription in Niccoli’s elegant hand, together with the copy made by the German scribe, spawned dozens of further manuscript copies—more than fifty are known to survive—and were the sources of all fifteenth-century and early sixteenth-century printed editions of Lucretius. Poggio’s discovery thus served as the crucial conduit through which the ancient poem, dormant for a thousand years, reentered circulation in the world.

Poggio may have distanced himself from the content of On the Nature of Things, but he took the crucial first step in pulling the poem off the shelf, having it copied, and sending the copy to his friends in Florence. Once it began to circulate again, the difficulty was not in reading the poem (provided, of course, one had adequate Latin) but in discussing its content openly or taking its ideas seriously.

The problem with Epicurus and Lucretius was not their paganism—after all, Aristotle too was a pagan—but rather their physics. Atomism absolutely denied the key distinction between substance and accidents, and therefore threatened the whole magnificent intellectual edifice resting on Aristotelian foundations. And this threat came at exactly the moment when Protestants had mounted their most serious assault on Catholic doctrine.

Indeed, atomism seemed to offer the Reformers access to an intellectual weapon of mass destruction. The Church was determined not to allow anyone to lay hands on this weapon, and its ideological arm, the Inquisition, was alerted to detect the telltale signs of proliferation.

But as Thomas More discovered when he tried to buy up and burn Protestant translations of the Bible, the printing press had made it maddeningly difficult to kill a book. And to suppress a set of ideas that were vitally important in enabling new scientific advances in physics and astronomy proved to be even more difficult.

Other interesting thoughts Lucretius had

  • The highest goal of human life is the enhancement of pleasure and the reduction of pain. Life should be organized to serve the pursuit of happiness. There is no ethical purpose higher than facilitating this pursuit for oneself and one’s fellow creatures.
  • The greatest obstacle to pleasure is not pain; it is delusion. The principal enemies of human happiness are inordinate desire—the fantasy of attaining something that exceeds what the finite mortal world allows—and gnawing fear.
  • Why are humans so unhappy? The answer, Lucretius thought, had to do with the power of the imagination. Though they are finite and mortal, humans are gripped by illusions of the infinite—infinite pleasure and infinite pain. The fantasy of infinite pain helps to account for their proneness to religion: in the misguided belief that their souls are immortal and hence potentially subject to an eternity of suffering, humans imagine that they can somehow negotiate with the gods for a better outcome, an eternity of pleasure in paradise. The fantasy of infinite pleasure helps to account for their proneness to romantic love: in the misguided belief that their happiness depends upon the absolute possession of some single object of limitless desire, humans are seized by a feverish, unappeasable hunger and thirst that can only bring anguish instead of happiness.
  • Understanding the nature of things generates deep wonder. The realization that the universe consists of atoms and void and nothing else, that the world was not made for us by a providential creator, that we are not the center of the universe, that our emotional lives are no more distinct than our physical lives from those of all other creatures, that our souls are as material and as mortal as our bodies—all these things are not the cause for despair. On the contrary, grasping the way things really are is the crucial step toward the possibility of happiness. Human insignificance—the fact that it is not all about us and our fate—is, Lucretius insisted, the good news.
  • It might seem at first that this comprehension would inevitably bring with it a sense of cold emptiness, as if the universe had been robbed of its magic. But being liberated from harmful illusions is not the same as disillusionment. The origin of philosophy, it was often said in the ancient world, was wonder: surprise and bafflement led to a desire to know, and knowledge in turn laid the wonder to rest. But in Lucretius’ account the process is something like the reverse: it is knowing the way things are that awakens the deepest wonder.  

The butterfly wing effect

What lay ahead, beyond the horizon of even these farsighted figures, were the astonishing empirical observations and experimental proofs that put the principles of ancient atomism on a whole different plane.  

When in the nineteenth century he set out to solve the mystery of the origin of human species, Charles Darwin did not have to draw on Lucretius’ vision of an entirely natural, unplanned process of creation and destruction, endlessly renewed by sexual reproduction. That vision had directly influenced the evolutionary theories of Darwin’s grandfather, Erasmus Darwin, but Charles could base his arguments on his own work in the Galápagos and elsewhere.

So too when Einstein wrote of atoms, his thought rested on experimental and mathematical science, not upon ancient philosophical speculation. But that speculation, as Einstein himself knew and acknowledged, had set the stage for the empirical proofs upon which modern atomism depends.  

That the ancient poem could now be safely left unread, that the drama of its loss and recovery could fade into oblivion, that Poggio Bracciolini could be forgotten almost entirely—these were only signs of Lucretius’ absorption into the mainstream of modern thought.

Among those for whom Lucretius was still a crucial guide, before this absorption had become complete, was a wealthy Virginia planter with a restless skeptical intelligence and a scientific bent.

Thomas Jefferson owned at least five Latin editions of On the Nature of Things, along with translations of the poem into English, Italian, and French. It was one of his favorite books, confirming his conviction that the world is nature alone and that nature consists only of matter. Still more, Lucretius helped to shape Jefferson’s confidence that ignorance and fear were not necessary components of human existence.  

Jefferson took this ancient inheritance in a direction that Lucretius could not have anticipated but of which Thomas More, back in the early sixteenth century, had dreamed. Jefferson had not, as the poet of On the Nature of Things urged, withdrawn from the fierce conflicts of public life. Instead, he had given a momentous political document, at the founding of a new republic, a distinctly Lucretian turn. The turn was toward a government whose end was not only to secure the lives and the liberties of its citizens but also to serve “the pursuit of Happiness.” The atoms of Lucretius had left their traces on the Declaration of Independence.

Other interesting facts/stories from the book

The technology of reading

Most books in the ancient world took the form of scrolls—like the Torah scrolls that Jews use in their services to this day—but by the fourth century Christians had almost completely opted for a different format, the codex, from which our familiar books derive. The codex has the huge advantage of being far easier for readers to find their way about in: the text can be conveniently paginated and indexed, and the pages can be turned quickly to the desired place. Not until the invention of the computer, with its superior search functions, could a serious challenge be mounted to the codex’s magnificently simple and flexible format. Only now have we begun once again to speak of “scrolling” through a text.

Changing culture of ‘genius’

Ancient Greeks and Romans did not share our idealization of isolated geniuses, working alone to think through the knottiest problems. Such scenes—Descartes in his secret retreat, calling everything into question, or the excommunicated Spinoza quietly reasoning to himself while grinding lenses—would eventually become our dominant emblem of the life of the mind. But this vision of proper intellectual pursuits rested on a profound shift in cultural prestige, one that began with the early Christian hermits who deliberately withdrew from whatever it was that pagans valued: St. Anthony (250–356) in the desert or St. Symeon Stylites (390–459) perched on his column. Such figures, modern scholars have shown, characteristically had in fact bands of followers, and though they lived apart, they often played a significant role in the life of large communities. But the dominant cultural image that they fashioned—or that came to be fashioned around them—was of radical isolation.

Not so the Greeks and Romans. As thinking and writing generally require quiet and a minimum of distraction, their poets and philosophers must have periodically pulled away from the noise and business of the world in order to accomplish what they did. But the image that they projected was social. Poets depicted themselves as shepherds singing to other shepherds; philosophers depicted themselves engaged in long conversations, often stretching out over several days.

The pulling away from the distractions of the everyday world was figured not as a retreat to the solitary cell but as a quiet exchange of words among friends in a garden. Humans, Aristotle wrote, are social animals: to realize one’s nature as a human then was to participate in a group activity. And the activity of choice, for cultivated Romans, as for the Greeks before them, was discourse.

The rise and fall of intellectual life – how the world lost its greatest assets

The fate of the books in all their vast numbers is epitomized in the fate of the greatest library in the ancient world, a library located not in Italy but in Alexandria, the capital of Egypt and the commercial hub of the eastern Mediterranean. The city had many tourist attractions, including an impressive theater and red-light district, but visitors always took note of something quite exceptional: in the center of the city, at a lavish site known as the Museum, most of the intellectual inheritance of Greek, Latin, Babylonian, Egyptian, and Jewish cultures had been assembled at enormous cost and carefully archived for research.  

Starting as early as 300 BCE, the Ptolomaic kings who ruled Alexandria had the inspired idea of luring leading scholars, scientists, and poets to their city by offering them life appointments at the Museum, with handsome salaries, tax exemptions, free food and lodging, and the almost limitless resources of the library.

The recipients of this largesse established remarkably high intellectual standards. Euclid developed his geometry in Alexandria; Archimedes discovered pi and laid the foundation for calculus; Eratosthenes posited that the earth was round and calculated its circumference to within 1 percent; Galen revolutionized medicine. Alexandrian astronomers postulated a heliocentric universe; geometers deduced that the length of a year was 365 ¼ days and proposed adding a “leap day” every fourth year; geographers speculated that it would be possible to reach India by sailing west from Spain; engineers developed hydraulics and pneumatics; anatomists first understood clearly that the brain and the nervous system were a unit, studied the function of the heart and the digestive system, and conducted experiments in nutrition. The level of achievement was staggering.

The Alexandrian library was not associated with a particular doctrine or philosophical school; its scope was the entire range of intellectual inquiry. It represented a global cosmopolitanism, a determination to assemble the accumulated knowledge of the whole world and to perfect and add to this knowledge.

Fantastic efforts were made not only to amass vast numbers of books but also to acquire or establish definitive editions. Alexandrian scholars were famously obsessed with the pursuit of textual accuracy. How was it possible to strip away the corruptions that inevitably seeped into books copied and recopied, for the most part by slaves, for centuries? Generations of dedicated scholars developed elaborate techniques of comparative analysis and painstaking commentary in pursuit of the master texts.

At its height the Museum contained at least a half-million papyrus rolls systematically organized, labeled, and shelved according to a clever new system that its first director, a Homer scholar named Zenodotus, seems to have invented: the system was alphabetical order.

The murder of Hypatia signified more than the end of one remarkable person; it effectively marked the downfall of Alexandrian intellectual life and was the death knell for the whole intellectual tradition that underlay the text that Poggio recovered so many centuries later. The Museum, with its dream of assembling all texts, all schools, all ideas, was no longer at the protected center of civil society.

In the years that followed the library virtually ceased to be mentioned, as if its great collections, virtually the sum of classical culture, had vanished without a trace. They had almost certainly not disappeared all at once—such a momentous act of destruction would have been recorded. But if one asks, Where did all the books go? the answer lies not only in the quick work of the soldiers’ flames and the long, slow, secret labor of the bookworm. It lies, symbolically at least, in the fate of Hypatia.

The other libraries of the ancient world fared no better. A survey of Rome in the early fourth century listed twenty-eight public libraries, in addition to the unnumbered private collections in aristocratic mansions. Near the century’s end, the historian Ammianus Marcellinus complained that Romans had virtually abandoned serious reading. Ammianus was not lamenting barbarian raids or Christian fanaticism. No doubt these were at work, somewhere in the background of the phenomena that struck him. But what he observed, as the empire slowly crumbled, was a loss of cultural moorings, a descent into febrile triviality. “In place of the philosopher the singer is called in, and in place of the orator the teacher of stagecraft, and while the libraries are shut up forever like tombs, water-organs are manufactured and lyres as large as carriages.”

When, after a long, slow death agony, the Roman Empire in the West finally collapsed—the last emperor, Romulus Augustulus, quietly resigned in 476 CE—the Germanic tribes that seized one province after another had no tradition of literacy. The barbarians who broke into the public buildings and seized the villas may not have been actively hostile to learning, but they certainly had no interest in preserving its material traces. The former owners of the villas, dragged off to slavery on some remote farmstead, would have had more important household goods to salvage and take with them than books. And, since the conquerors were for the most part Christians, those among them who learned to read and write had no incentive to study the works of the classical pagan authors. Compared to the unleashed forces of warfare and of faith, Mount Vesuvius was kinder to the legacy of antiquity.

Fast forward thousands of years and even the most celebrated monastic libraries of the Middle Ages were tiny in comparison with the libraries of antiquity or those that existed in Baghdad or Cairo. To assemble a modest number of books, in the long centuries before the invention of the printing press forever changed the equation, meant the eventual establishment of what were called scriptoria, workshops where monks would be trained to sit for long hours making copies. At first the copying was probably done in an improvised setting in the cloister, where, even if the cold sometimes stiffened the fingers, at least the light would be good. But in time special rooms were designated or built for the purpose. In the greatest monasteries, increasingly eager to amass prestigious collections of books, these were large rooms equipped with clear glass windows under which the monks, as many as thirty of them, sat at individual desks, sometimes partitioned off from one another.