How Painters Learned to Show Depth: The Invention of Perspective

A Looking at a painting made in medieval Europe, a modern viewer is often struck by a curious flatness. Figures seem to float against gold or plain backgrounds, buildings are shown from impossible angles, and there is little sense of a believable space receding into the distance. This was not because medieval artists lacked skill. Rather, they were not attempting to reproduce the way the eye actually sees the world. The size of a figure in such a painting frequently indicated not how near it stood but how important it was: a saint or a king might tower over lesser mortals, regardless of where each was supposed to be standing. Space, in this tradition, was arranged according to meaning rather than optics, and a painter's task was to make the sacred order of the world visible, not to trick the eye into seeing a room or a landscape that was not really there.

B The change that transformed European painting began in the Italian city of Florence in the early fifteenth century. Its central figure was an architect and goldsmith named Filippo Brunelleschi, who is credited with the first convincing demonstration of what we now call linear perspective. According to the traditional account, Brunelleschi painted a small panel showing a well-known Florentine building and devised an ingenious optical experiment, using a mirror, by which a viewer could compare his painted image directly with the real building behind it. The painted scene matched the real one so closely that the effect was startling, and it showed that the appearance of depth could be captured on a flat surface by strict geometrical means.

C The principle Brunelleschi demonstrated is simple to state, though its consequences were enormous. In linear perspective, lines that are in reality parallel, such as the two edges of a straight road or the sides of a building, appear to draw closer together as they recede, until they seem to meet at a single point on the horizon. This point is known as the vanishing point. By constructing a picture so that all such lines converge correctly upon it, an artist could create a powerful illusion of three-dimensional space on a two-dimensional wall or panel, so that the viewer seemed to be looking through the surface into a real world beyond.

D A demonstration, however impressive, is not the same as a method that others can learn, and the wider triumph of perspective owed much to those who turned Brunelleschi's insight into teachable rules. The most important of these was the scholar and architect Leon Battista Alberti, who set out the principles of perspective in a written treatise on painting. Alberti explained, in orderly steps, how a painter should construct a perspective scheme, providing the geometry and the reasoning behind it. His treatise transformed perspective from a closely guarded trick into a body of knowledge that any educated artist could study and apply, and it did much to spread the new technique beyond Florence.

E Perspective quickly moved from theory into practice. The painter Masaccio, working in Florence at the same period, applied the new geometry to a religious fresco on a church wall, creating so convincing an illusion of depth that visitors felt they were looking into a chapel that did not really exist, its architecture apparently extending back into the solid wall. Such works demonstrated the sheer power of the technique and its capacity to astonish, and within a few generations the mastery of perspective had become a basic part of the training of painters across Italy and, before long, the whole of Europe.

F For all its influence, perspective is not, as is sometimes assumed, simply the 'correct' way to depict the world, against which all other approaches must be judged as mistakes. It is one method among several, a set of conventions developed in a particular place and time to achieve a particular effect. The art of many other cultures represents space in quite different ways, deliberately and with great sophistication, and even in Europe artists would later break the rules of perspective for expressive purposes. Understood in this light, the invention of perspective is not the moment when painters finally learned to see correctly, but the moment when one powerful way of organising a picture was worked out, written down and passed on.