ExLatinis: Recovering the Early Modern Mind

From the Latin, into the open

Latin carried the learned conversation of Europe for three centuries after the printing press before it slowly fell out of use. Today, very few are able to read the vast record of early modern thought. ExLatinis is an attempt to increase public access to that history, beginning with five texts that share the humanist impulse behind the project itself: ad fontes, a return to the source.

The aspiration to gather up all knowledge and set it before the public is old and venerable. When Diderot and d'Alembert set hundreds of contributors loose on the Encyclopédie in eighteenth-century France, they did so in the belief that knowledge should circulate freely, within reach of any reasoning person. They knew, of course, that an encyclopedia containing all human knowledge would never be complete. The project stands just as much for the impossibility of total knowledge as for its promise. But it was by aiming at something that lay beyond reach that its makers accomplished more than a soberer effort could have.

It is with the same self-conscious hubris that Leo, the company behind this project, has begun to assemble public collections of archival material. Leo Collections is the foundation for a larger ambition, described elsewhere, to create a single, interoperable archive of the world's textual past, drawn from holdings scattered across national repositories, local archives, university libraries, and the hard drives of individual scholars. 

ExLatinis is the first leg of this effort. It sets out to translate every Latin work printed in Europe between 1450 and 1750, a span bookended by the printing press, which enabled a single book to reach many more readers, and the turn to the vernaculars, which left command of the language to a shrinking few.

The lost language of the learned

In early modern Europe, a work printed in Basel could be read, annotated, and rebutted in Kraków or Salamanca without the need for any intermediary to translate it. Latin was the lingua franca of the learned, in which those who shared no mother tongue puzzled together over the soul, the motions of the planets, and the words of God. The majority of printed works that enjoyed any significant circulation during this period survive. Though many have been scanned and made available in online repositories such as Google Books and the Internet Archive, they are little read, because the language that once facilitated communication across borders is now inaccessible to almost everyone.

Latin's demise as the common tongue of learning was not foreordained. Two impulses pulled at it from opposite directions. The first was the recovery of classical antiquity that began in northern Italy at the turn of the fourteenth century, summarized by its adherents in the phrase ad fontes, "to the sources." The humanists studied the texts of ancient Greece and Rome in their original forms, stripped of what they saw as corruptions accumulated over the intervening centuries. As the program spread northwards over the next two hundred years, its devotees hoped not just to imitate the greatness of the ancients but, by refining Latin as the medium of an international scholarly class, to restore the linguistic unity lost at Babel.

The second impulse worked from the same instinct, distrusting inherited assumptions and proposing to go back to the original source. When Luther initiated the break with Rome in 1517, he called for a return to the original word of scripture, untainted by the errors of the Vulgate and the accumulated gloss of the schoolmen. But where the humanists wrote for a learned class in purified Latin, the reformers wanted to bring the sense of the original to every believer, in their own tongues. The church's Latin, they argued, served less to transmit the word than to ration it.

Slowly, the champions of the vernacular won. Every successive generation read less of it, rendering the Protestant charge of esotericism ever more true. The result was that written output of early modern European thinkers became increasingly inaccessible, making way for a murky haze of secondhand impressions and convenient caricatures. 

Just as the humanists lamented the corruptions that had crept into the monuments of antiquity, so their own age came to be misrepresented as one of clean breakthroughs, of reason shrugging off medieval superstition. But their return to the sources acknowledged no such boundary. The picture that emerges from these texts is much richer and stranger.

Veritas Temporis Filia ("Truth is the Daughter of Time"), engraved by Jan Collaert II. Time carries Truth up into the light while Envy lies defeated below. Source ↗.

Technology and the promise of recovery

Though humanists and reformers parted ways over whom the recovered word was for, they both asked whether to trust the text at hand and proposed to resolve the question by returning to the original source. ExLatinis adopts the same approach but turns it on the early modern record itself.

Digitization efforts since the 1990s have made vast numbers of these works widely and freely available. The problem is that actually reading them requires a working knowledge of Latin and translating them at scale depends on something apparently banal: the ability to turn photographs of pages into text that a machine can read.

Optical character recognition, the technology that converts an image of a page into searchable characters, was built for the type of the twentieth century and tends to malfunction on early modern print. The long ſ is easily read as an f; the ligatures that fuse two or three letters into a single character are rendered as confusable homoglyphs; abbreviations, in which a stroke above a vowel stands for a missing m or n and which often require contextual clues to parse, are effaced entirely.

A newer technology powered by AI, known as handwritten text recognition, or HTR, has in recent years made enormous progress, including on difficult print. Though not flawless, the best models now generate usable transcriptions for most purposes. They hold up on damp-stained paper, on ink bleeding from the far side of a leaf, on photos taken with phones in shaky hands. Helpfully, a model trained on handwriting can also read the marginalia, the underlinings, the interlinear glosses, to record how a text was read.

ExLatinis puts this technology to work in an automated pipeline: a chain of small, specialized steps in which the output of one becomes the material for the next, like a workshop dividing labor among hands. The process begins by searching open repositories for Latin works photographed decades ago but never translated. It then uploads each one to Leo, whose state-of-the-art HTR model—which shares the same architecture as general-purpose systems like GPT, Gemini, and Claude, but has been trained for the specialized task of reading historical documents—transcribes each page individually. An external large language model then translates the text into modern English, before a research stage summarizes, references, and interprets the work in passes. The final steps comb the volume for its illustrations like historiated initials and engraved title pages, weaving them into a final companion report, which is then posted to our website.

Left unchecked, the danger of an automated process like this is that it will tend to produce something fluent but unmoored, making confident claims with no basis in the original text. The pipeline therefore builds in verification at several points. The research stage works from chunks of the transcription rather than from what the model carries in memory. Throughout the drafting process, the pipeline checks each claim back against the source and catches stray passages before they reach the final report. Because these safeguards are not infallible, a second principle of discipline turns to the reader. The companion report is designed to make answerability to the source visible, tying claims to the exact place in the original text that ground them. Clicking a link in the report takes the user to the page it came from, where the image, its Latin transcription, and the English rendering appear together in Leo's interface. The reader is invited to take up the position of the skeptical humanist, to catch the error and to correct it.

It goes without saying that machine-generated transcriptions and translations are no substitute for those made by scholars with judgment honed over years. Of the three layers, the generated report is the most likely to make plausible-sounding errors, and it should be used strictly as a prompt for discovery and a finding aid rather than taken as a work of scholarship. Though every effort has been made to ensure fidelity, all of these layers will sometimes produce flawed output.

There are many legitimate grounds for caution about using AI in historical research. A student who simply defers to a machine will never build the judgment that only years of construing can produce, and no automated report, however fluent, should be cited as though a thinking person had written it. But it does not follow that because a rendering is imperfect, the material is better left unread altogether. That argument is suspiciously close to the one made by church- and schoolmen who preferred the laity dependent on those licensed to read for them than at liberty to misread on their own. What ExLatinis offers is not a final authority but a provisional reading with swift passage back to the source, in a form that invites inspection rather than blind trust.

Even in an imperfect form, making this material available offers a way back into a vanished mental world. Where the famous, long-translated canonical works reveal an intellectual culture at its most deliberate and self-conscious, the broader literary hinterland is in many ways more revealing. To translate that work in bulk promises to put a whole texture of thought within reach of anyone, rather than reserving it for the few who can still read it in the original.

From coins to comets

We begin the project with a sample of five non-canonical Latin texts. Taken together, they span the project's arc, from the first decades of print to the eve of Latin's retreat. Their subjects range from coins to comets, but they are united by a habit of mind. The recovery of antiquity taught early modern scholars to distrust the text while confessional quarrels raised the question of who was entitled to make any given claim. Repeatedly in these texts, an old certainty is questioned on the strength of evidence presented by the source.

The summaries below were generated by the pipeline itself, from each work’s companion report and, behind that, from the raw transcription, demonstrating the process described above.

Guillaume Budé, De Asse et partibus eius libri quinque (Paris, 1514)

The Parisian jurist Guillaume Budé kept a balance and a set of small weights on his desk, in view beside a handful of ancient gold and silver coins, so that he could weigh everything exactly. From those weighings he set out to recover what a Roman aureus was actually worth. Where a manuscript and a surviving coin disagreed, the coin was the better witness, and Budé licensed the whole procedure on a flat refusal of deference. The ancients, he held, “were men as we are,” who sometimes merely wrote down what they had understood from their fathers. Much of the corruption he hunted turned on one mistake copied down for centuries, which he called the cardo totius operis, the hinge of the whole work. Sestertium, an abstract unit meaning a thousand sesterces, had been confused with the coin in the hand, so that a state's revenue might be reckoned a hundredfold too high or too low. Once the error was fixed he could revise Roman history at scale, reading the equestrian census as contracted from five hundred to four hundred thousand sesterces, or calculating that Caligula dined on ten million in a single day. 

Leonardo Vairo, De fascino libri tres (Paris, 1583)

In this work, a Benedictine demonologist, later bishop of Pozzuoli, begins an examination of the evil eye by surveying traditional arguments. Vairo gathers every natural explanation, from the altering imagination and the radiating eye to the contagion of touch and the influence of the stars, and gives each its strongest form, crowning the eye king of the senses, the organ nearest the soul and the likeliest channel for harm crossing open air. Then he turns it all on its head. Drawing on the anatomy of Pietro d'Abano, he argues the eye was made for seeing, built to receive rather than to strike. The imagination deals only in likenesses, never the things themselves. If no natural power can carry the harm across the gap, what remains must belong to demons working through a pact. His vivid case is a bride at Sepino, where a demon left the husband untouched but corrupted the images through which she saw him, until he seemed so painted over with monsters that she would sooner die than endure him. The whole argument relocates bewitchment from the body to the soul: what exposes a person is not their constitution but their contempt of divine law, and the remedies are accordingly not medical but theological.

Erycius Puteanus, De cometa anni 1618 (Cologne, 1619)

Puteanus, who held Lipsius's old chair of eloquence at Louvain and counselled Archduke Albert, refused to read the great comet of 1618 as a warning of war, even though it appeared six months after the Defenestration of Prague, at the opening of the Thirty Years' War. Aristotle termed the comet ignis, a terrestrial exhalation kindled below the Moon—by definition a thing of the corruptible lower world, and so a fit herald of earthly disaster. Puteanus reclassified it as lumen, a harmless radiance living above the Moon among the orderly and unchanging heavens, writing that where others choose Fire he preferred a gentle Light. He drew on the new astronomy uncovered by the telescope, which had begun to erode the old boundary between a changeable sublunary realm and an eternal one above. In doing so he reversed the logic of prophecy, arguing that comets do not herald wars, but that never-ending wars get pinned on whatever comet came first.

Ottavio Ferrari, De re vestiaria libri septem (Padua, 1654)

A professor at Padua, Ferrari reconstructed the dress of Greece and Rome by examining surviving statues, coins, and reliefs. Visual evidence came first, with text used only as reinforcement. From the marbles he pronounced the toga round and closed, against Sigonio's long-standing thesis that it was square and open. What emerged through his work was a new understanding of the role of dress in hierarchy: the purple stripes dividing senator from knight, cloaks graded by the coarseness of their wool, the philosopher's threadbare tribonium advertising its owner's asceticism, a lineage he traced forward into Christian monastic dress. But the method depended on things he did not own. When a once-generous benefactor took back the bronzes with which the remaining chapters were to be illustrated, Ferrari used spoliauit, the word for stripping a corpse, for the resulting gaps in the plates.

Nugae venales, sive Thesaurus ridendi & jocandi (c.1630s–1720)

Assembled anonymously and reissued for nearly a century, Nugae venales applies the full apparatus of university learning—syllogism, medical thesis, legal will, disciplined Latin verse—gravely to farts, freshmen, drunkards, and pigs. It asks, in the deadpan of the scholastic disputation, whether breaking wind is a bodily thing, and answers with a syllogism that observes every rule of demonstration: nothing is so perceptible as a fart; therefore a fart is a body. A dying piglet dictates its will in flawless courtroom Latin, citing Jerome for authority and apologizing that it cannot sign with its own hand. The joke lands only because the forms stay perfectly intact, revealing how much of a scholar's authority lived in the form rather than the matter. It carries the game onto its own title page, printed, it claims, at Nobody's shop yet on sale everywhere, its imaginary publishers christened after the three Magi—Caspar Myrrh, Master Frankincense, Balthasar Gold.

Back to the source

Each of these texts overturned a received authority by returning to the source: the weighed coin against the copied figure, the new astronomy against Aristotle, the marble against Sigonio. ExLatinis turns the same appeal on the early modern record itself and promises, with the tools of the twenty-first century, to place what it recovers within reach of anyone.

ExLatinis will release new texts as they are translated. You can explore the collection on our blog or via our shared folder on Leo. Follow the project on Instagram, Bluesky, X, and Facebook to know when the next text is ready.