How Perspective made the Modern World
Posted by Darin Hayton on 10/13 at 10:53 PM
Samuel Y. Edgerton argues in his new book, The Mirror, the Window, and the Telescope. How Renaissance Linear Perspective Changed Our Vision of the Universe (Ithaca, NY: Cornell University Press, 2009) that linear perspective made possible modern science, the discovery of the New World, and Neil Armstrong’s walk on the moon. This book extends an thesis he first defended more than thirty years ago in his The Renaissance Rediscovery of Linear Perspective (New York, 1975). He refined his thesis in a various articles and in his The Heritage of Giotto’s Geometry: Art and Science on the Eve of Scientific Revolution (Ithaca, NY: Cornell University Press, 1991). His latest efforts to renew this argument were prompted by a “concern that the subject of perspective in the arts has fallen victim to a new wave of art criticism that no longer considers it a positive idea” (p. xiv).
In brief, Edgerton’s argument can be summarized:
In 1425 Filippo Brunelleschi demonstrated linear perspective within the profoundly religious context of early 15th-century Florence. His first two perspective paintings (now lost) had an immediate influence on his contemporaries. Brunelleschi’s rules for making perspective drawings, which relied on the use of a mirror, were later codified by Leon Battista Alberti in his De pictura. By using the window technique, Alberti’s text began the process of secularizing perspective. Within this new context, linear perspective encouraged a secularized understanding of space that laid the foundations for the Scientific Revolution. Galileo’s use of the telescope to look at the moon and his use of basic geometry to estimate the height of the mountains on its surface represent for Edgerton the key shift to a fully modern, secularized use of perspective.
The longer summary:
According to Edgerton, Giotto de Bondone’s Assisi and his Arena Chapel frescos need to be understood not as precursors to later perspective paintings or attempts to represent real life, but were instead intended as devotional tools. Giotto’s frescos memorialized Christian miracle plays. They were objects for reflection and meditation. For Edgerton, it is significant that Giotto’s frescos have some non-real, religious referent.
Edgerton argues that Giotto wasn’t the source for later perspective painting. Instead he locates the source in medieval thinkers, especially Roger Bacon and Peter of Limoges, who understood both geometry and the medieval science of optics as important tools in the Christian hopes of recovering the Holy Land and converting infidels. Bacon’s work, especially De multiplicatione specierum, was widely discussed in early 15th-century Florence and influenced the most important religious leader, the Dominican priest Antonino Pierozzi. His sermons on the nature of sin and salvation are replete with optical metaphors and analogies.
Brunelleschi’s efforts to develop linear perspective only make sense within this religious context and the moralized theories of vision that were pervasive in Florence at the time. Brunelleschi drilled a hole through the center of his first perspective painting and instructed his audience to look through it at the painting’s reflection in a mirror. His use of the mirror was a visual confirmation of Paul the Apostle’s claim about spiritual vision in 1 Corinthians 13:12: “For now we see but a poor reflection as in a mirror; then we shall see face to face.”
In 1435 Alberti codified Brunelleschi’s rules in his own De pictura. Alberti simplified the mathematics by replacing Brunelleschi’s mirror with a gridded window. The artist looked through the window and copied the contents of each square of the grid onto his canvas. Edgerton argues that this shift away from the mirror began the process of secularizing perspective. No longer did the artist or the viewer of the final painting look at a mirror image of the world, but viewed the real world disciplined by the rules of geometry and perspective. By looking at the real world, Alberti’s method had removed much of the spiritual significance of perspective and represented an important step toward Galileo’s use of perspective.
Galileo was familiar with efforts to treat linear perspective as part of theoretical mathematics through colleagues and patrons, notably Frederico Commandino and Guidobaldo del Monte. When looking at the moon through his telescope, he used their techniques to estimate the height of the mountains and the depths of the craters he saw on its surface. It was Galileo’s application of the theoretical rules of perspective to the reality of the moon’s surface that represents, for Edgerton, the final secularization of perspective and its complete appropriation by the emerging, modern science. Proof of Galileo’s achievement and the importance of perspective for modern science is demonstrated, according to Edgerton, by comparing Galileo’s work with that of Thomas Hariot. Because he lived in medieval England, Hariot was unable to recognize the features that Galileo identified as topography. For Hariot, they remained light and dark areas; whereas for Galileo, those same areas were evidence of lunar topography. Here, perspective is used as a tool to understand reality.
Edgerton’s book succeeds best when it focuses on reconstructions of Brunelleschi’s and Alberti’s perspective methods. His analyses of paintings, especially his reconstruction of the perspective systems that structure them, are instructive. His book is less successful in its broader argument about linear perspective and modern science. The last chapter, on Galileo, is too brief to support Edgerton’s. His selective use of Galileo’s work and the secondary literature on Galileo will strike historians of science as problematic and points to a larger problem with this book. Edgerton, at times, builds his argument on thin evidence. And while his claims are often plausible, their lack of sufficient foundation prevents them from being persuasive (e.g., his claims about the popularity of Bacon’s theory of specie in early fifteenth-century Florence on pages 30–32 and again 36; or his claim that anybody viewing Raphael’s paintings would have seen them as “synonymous with Alberti’s ideals” on page 132–3; or his implication that Galileo’s works introduced the Renaissance into England on page 164–5). We are often given rational rather than historically convincing reconstructions. Further, and perhaps most problematic, Edgerton’s monocausal explanation for the rise of modern science is disturbing and sounds like a form of post hoc, ergo propter hoc argument (for a partial history of such efforts, see Floris Cohen, The Scientific Revolution: A Historiographical Inquiry).
Edgerton’s real accomplishment is providing a clear explanation and reconstruction of the perspectival systems in fifteenth-century Florentine painting. As an introduction to Renaissance linear perspective, this is a great book. As an argument about the cause of modern science, including digital photography, this book is less successful.