How to See Like a 17th-Century Friar

A major new study puts the visual paradoxes and optical illusions of baroque art at the heart of theological debates of the Counter-Reformation.

By Emanuele LugliFebruary 13, 2026

• Philosophy & Religion

• Art & Architecture

WATCHING A FOOTBALL GAME, you’ve seen them: those warped advertisements painted directly onto the turf that look, from the broadcast camera’s elevated vantage, like upright freestanding billboards, perfectly two-dimensional. Marketers, a little too dryly, call these “illusion ads,” but the proper term is “anamorphoses”; in their 17th-century heyday, rather than selling cars or flights to TV audiences, they were serious academic business, taught as part of the mathematics curriculum in universities across Europe. One of the textbooks for students of anamorphosis was a 1638 volume titled La perspective curieuse (which I’d translate as “The Unusual Perspective,” since “curieux” at the time described a lover of rare things). Like most geometry manuals, it begins with the basics: how to draw a square, how to nest a pentagon inside a circle. Then it pivots to perspective, those instructions for rendering three-dimensional objects on a flat surface. Perspective was, by then, a science with a 200-year history; every artist since the Renaissance understood its rules, and its tricks were deployed everywhere from provincial villas to theater stages, where city backdrops, barely deeper than a few steps, persuaded audiences that they were gazing down streets stretching miles behind the actors.

But La perspective curieuse goes beyond the conventional to explain some of the most dazzling feats of the new optical sorcery. Perspective depends on the viewer occupying a single, fixed position, and it is possible to exploit that fixity. You can build an image that appears utterly illegible from one point but resolves into something perfectly coherent from another. La perspective curieuse describes a sheet of paper folded into sharp V-shaped pleats, like an accordion: stand on one side and you see a king; shift to the other, and you read a text instead. Or consider those sprawling, fanlike illustrations that at first appear as nothing more than a haze of smeared lines, until you position a silver cylinder at their center. In the reflection, the chaos resolves instantly: a hulking rhinoceros or a saint praying, tear-brimmed eyes lifted toward the sky.

The effect wasn’t merely clever; it was destabilizing. It made you an accomplice in your own delusion. You could stare at an image for minutes and see only nonsense, and then, with the introduction of a single prop, the truth would snap into view. It felt less like witnessing a magic trick than being handed evidence of your own suggestibility: proof that reality was negotiable, that your angle of vision was everything, and that you could, with instruction, be led into seeing what was there all along.

La perspective curieuse was the work of Jean-François Nicéron, a friar of the Order of Minims. He wrote the treatise in his late twenties and was dead by 38. In that brief, feverish span, he seems to have devoted himself to anamorphosis with monastic zeal. He painted elaborate anamorphic scenes on the walls of his Parisian convent, none of which, unfortunately, survive. One of the few comparable murals can be seen in another Minim convent, in Rome: a spectacular eruption of gray-brown bark and leafed tendrils that seem to slide and buckle across the wall, dragged over magma-like layers of pigment, as if the surface itself had been pulled while the paint was still wet. Outside, tourists stream down the Spanish Steps, unaware of this delirious experiment in perception. The Minims lived in near-perpetual fasts and took vows of poverty so severe they refused even to own property. Why did they, of all orders, become such patrons of optical illusions? The question had never been fully answered until now.

In The Deformation: Attention and Discernment in Catholic Reformation Art and Architecture (2025), art historian Susanna Berger suggests that the 17th-century obsession with anamorphosis wasn’t mere novelty; it was a theological gambit. The distortions—the sudden, almost violent revelations of the hidden image—were a meditation on perception itself, a reflection on the fragility of knowledge and the mysterious structures of divinity. To look at an anamorphosis, in other words, was to confront faith not as doctrine but as experience: the world as it appeared, and the truth lurking just beyond the edge of vision, waiting for you to shift your stance and discover what had always been there.

The Catholic faith—that great edifice of paradox, where sons are fathers, wine becomes blood, and a virgin gives birth—has always thrived on enigma. Mystery is the very oxygen that keeps belief alive. Berger traces one source of this atmosphere to St. Paul’s verse “videmus nunc per speculum in enigmate.” The common English translation—“now we see through a glass, darkly”—flattens the precision of the Latin of the Vulgate, which doesn’t suggest we’re squinting through fog, but rather declares that we can only see enigmas through a speculum, a mirror, or a pane of glass. As Berger notes, “speculum” also carries the weight of example, as in the “specula principum,” the handbooks in which medieval rulers studied the admirable conduct of their predecessors. The implication is that understanding doesn’t emerge from pure contemplation. It requires mediation: a tool, a text, or someone who can change what we see. Divine meaning, in other words, never arrives raw. It can only be grasped through something else, and in passing through that lens, it is always reduced and deformed.

Berger uses the term “deformation” as a conceptual net, wide enough to capture the variety of tools employed to resolve even the most confounding dogmas when seen from the right point of view: concave mirrors, illustrations of flowers believed to carry the instruments of the Passion, celestial diagrams bending the heavens into new shapes. She stretches the term to its limits: for Berger, deformation is anything—any idea, any object—“that fails to meet” an ideal.

In early modern Europe, this was a real concern. Architects worried about how to design buildings that would not appear deformed from a distance. Bishops fretted that new interpretations of doctrine hadn’t so much reformed the church as deformed it, though as Berger reminds us, the terms “Reformation” and “Counter-Reformation” were not in use at the time. They were retroactive labels, introduced by 18th-century scholars eager to discern a pattern in the chaos. Even the word “anamorphosis” had yet to enter the conversation; those optical illusions were called “curious perspectives” or, sometimes, “artificial magic.” That’s the historian’s thankless task: to reveal how our understanding of the past is itself a kind of distortion, how every act of writing history requires a perspective inevitably warped by the present.

Berger urges us, instead, to use “deformation” and thus see the 17th century not as a battlefield of rigid ideologies but as a world captivated by questions of form and the bending of norms. In that light, anamorphoses emerged as ways of negotiating what was right and when it was right. The church, naturally, had a vested interest in the answers. As Berger observes, “illusionistic imagery was seen as crucial to advancing the messages of the Church—and its authority as a mediating figure able to decode truths that might be hard for the laity to interpret.” For the Minims and Jesuits, anamorphosis served a dual purpose: it demonstrated how doctrinal mysteries required careful explanation while simultaneously establishing intellectual hierarchies. Even when the trick was revealed, the common people lacked the education, the materials, and the spatial reasoning to reproduce it themselves. They weren’t just initially blind to the hidden geometries; even after the illusion was explained, they also remained dependent on the clergy—those Latin-speaking, math-trained men who alone could navigate the world’s hidden structures. In this way, deformation aligns closely with the Counter-Reformation’s most elitist tendencies. While Luther’s Reformation had at least theoretically considered the common worshipper, deformation was fundamentally an exercise in exclusivity. Its practitioners floated above the masses, secure in their superiority, for they could explain what most people perceived as “miracles.”

Central to The Deformation is the question of how religious elites wielded anamorphosis as a means of gatekeeping the divine. That is precisely what makes Berger’s argument fresh. In the sloppiest takes, anamorphoses get lumped in with the baroque’s general appetite for “meraviglia,” that catchall term for wonderment, as if a culture so obsessed with surprising its spectators had never bothered to invent ways of differentiating between forms of astonishment. Other accounts flatten anamorphosis into a mere extension of perspective, as if it were nothing more than the next logical step, which, conveniently, is exactly what La perspective curieuse wants you to believe. Most studies before The Deformation did the same thing: Jurgis Baltrušaitis’s Anamorphic Art (1969) and Lyle Massey’s Picturing Space, Displacing Bodies: Anamorphosis in Early Modern Theories of Perspective (2007) trace perspective like a straight line from its measured Italian beginnings to its most daring mutations in France. Their arguments tend toward the intellectual and, when they do, come close to Berger’s. Baltrušaitis observes how these optical games always unfolded against “a background of inquiry about reality and the world of appearances,” while Massey sees anamorphosis as forcing viewers to confront their own subjectivity. Yet their scope, covering centuries and multiple countries, is vast, and so their insights, however brilliant, remain tantalizingly broad. Berger narrows the field: a single century, barely even that, and a tight geography, with Rome dominating four of her six chapters, followed by brief detours to Northern Italy and Germany. Most of her protagonists are members of ecclesiastical elites. This isn’t broad-stroke art history; it’s a targeted excavation. Where Baltrušaitis and Massey spin a dazzling tapestry of anamorphic art as a universal language of distortion, Berger picks apart the doctrinal seams, tracing the tricks of optics through the era’s thorniest theological debates, such as the fight over whether the Eucharist literally became Christ’s flesh.

Berger’s book aligns more closely with the theoretical literature on perspective, particularly the formidable tradition that treats it not as a collection of artistic techniques but as a cognitive architecture. This is the lineage running from Erwin Panofsky’s Perspective as Symbolic Form (1927) through Hubert Damisch’s The Origin of Perspective (1987), which revealed perspective to be far more consequential than a mere mathematical trick for rendering space. These scholars showed how perspective actively constructs our relationship to reality, imposing a strict hierarchy between the sovereign viewing subject, positioned as the organizing intelligence, and the object world, reduced to what presents itself frontally to our gaze. The cultural and intellectual implications are profound: Descartes’s mathematical universe would have been unthinkable without perspective’s prior conquest of visual representation. Yet, as Damisch meticulously demonstrates, the system carries its own critique. Its assumptions collapse spectacularly when we step outside the privileged viewpoint, a collapse that anamorphosis enacts with dazzling clarity. Ultimately, Berger’s project is about epistemology disguised as material culture. Perhaps the closest book to hers is Hanneke Grootenboer’s The Rhetoric of Perspective: Realism and Illusionism in Seventeenth-Century Dutch Still-Life Painting (2005), which argues that painting functions much like thought itself. Or, better perhaps, Berger continues the work she herself began in her previous book, The Art of Philosophy: Visual Thinking in Europe from the Late Renaissance to the Early Enlightenment (2017), which examines how images become vessels for thought.

Beyond anamorphoses, The Deformation delivers an array of breathtaking artifacts: ivory goblets carved with lacelike delicacy, church ceilings that appear to have exploded to release a crowd of angels, Borromini’s perspectival gallery in Rome’s Palazzo Spada, which Berger brilliantly situates within Bernardino Spada’s broader obsession with architectural deformations. But these wonders are not mere curiosities. Each object is a case study in a facet of 17th-century thought, shedding light on a specific intellectual framework.

Berger’s book is lavishly illustrated, with crisp, thoughtfully arranged images, and that matters more than you might think, given how closely she analyzes the layouts of the treatises she studies. Many of the photographs, taken by Berger herself, are not mere documentation; they are arguments in visual form. More than merely showing the objects she writes about, the images stage them, pulling you close, letting you grasp a fresco almost as if you were walking past it. There are foldouts too, and—here’s the real delight—a reflective silver sheet tucked inside an envelope, a clever little tool that lets you decode certain anamorphic images. (This is also a nod to tradition: Baltrušaitis included a similar reflective square, as did Fred Leeman in his 1975 book Hidden Images: Games of Perception, Anamorphic Art, Illusion.)

Berger is generous in crediting those who came before her: scholarship is a collective endeavor, a slow accretion of insight. There is even a faintly museum-label quality to the book’s habit of appending life dates—Thomas Aquinas (1225–1274)—which, if intended to help the uninitiated keep track of chronology, feels a little quaint to me. While I have done something similar in this review, noting the publication date of each book, the effect in The Deformation is to confine ideas to a specific era. Minims and Jesuits did not read Aquinas to encounter past ideas; they read Aquinas because he reached for something eternal in doctrine. Still, the footnotes are plentiful and the bibliography exhaustive, a gift to anyone eager to explore further. But what lingers isn’t only the research. It is also the way Berger’s book compels you to see differently, the way it makes a historical moment snap into focus, more faceted, more sharply edged than it looked from a distance—history rendered newly legible through the same uncanny recalibration that anamorphosis demands.