In the comedy series Father Ted, the curate, Fr Dougal, is (characteristically) finding it difficult to understand why far away cows look smaller than they really are. Ted’s explanation about big cows (near) and little cows (far away) never quite gets home.

But there was, historically, far more to perspective and its spiritual significance than even Ted realised. 

The discovery of geometric perspective in the 15th century seemed almost magical, and changed the perceived power and status of artists into stewards of what was regarded by Marsilio Ficino of the Platonic Academy of Florence as the circuitus spiritualis. The term was used to describe perspective as a grand narrative arrangement of objects and persons in space that connected the viewer to the eternal, or the divine, by way of the vanishing point, fully accessible only at infinity. Perspective was a sort of spiritual revelation, although the Church had concerns with Neoplatonic ideas about ‘God'. (In ancient Egypt the varying sizes of figures had indicated, not their proximity to the viewer—like big cows—but their relative importance in the earthly or heavenly order. The Chinese system indicated distance by arranging subjects vertically, in parallel.) 

Somewhat earlier, around 1415, Filippo Brunelleschi, designer of Florence’s famous dome, made a small foreshortened perspective painting of the baptistery, with a hole cut where the structure’s lines met at a vanishing point. He invited incredulous viewers to look from the rear of the panel, through the hole, at a mirror which Brunelleschi held so they could see how perpsective worked. But it also meant that the viewer could see his or her own eye at the point of infinity. Renaissance perspective had done what painting had not accomplished before: it placed the viewer in the scene itself, and somehow also at the point of infinity. This fitted in with the Neoplatonist philosophy of the day. In 1435 Leon Battista Alberti, a friend of Brunelleschi, had written a treatise titled De pictura in which he described perspective as 'a contemplation of infinity', and ‘an aid to religion’. Piero della Francesca’s Flagellation of Christ (illustrated) demonstrated how the clear linear perspective drew the viewer’s eye to key elements of the picture (Jesus) and led to the infinity of the vanishing point. Raphael did the same in his great painting of The School of Athens, with perspective lines focussing on Plato and Aristotle.

After the Renaissance, especially during the period known as mannerism, linear perspective played much less of a role. The artist’s concern was turned inwards, the direction of spiritual focus upwards rather than outwards, like a vertical flame (El Greco). During the Baroque period reflected light played the role that had formerly been taken by the vanishing point. Light travelled, so it was thought, at infinite speed, and jumped back to the viewer from a much closer source. Form, revealed through the strong light-dark patterns of chiaroscuro (think Caravaggio), had replaced architecture’s perspectival lines and vanishing points. In the Neoclassical period the grand historical tableaux restored linear architectual perspective, but the viewer was no longer invited to the scene in a contemplative vision of the infinite as he had been in the Renaissance. The Neoclassical tableau was temporal and historical, not eternal; it was a sealed world fixed in time. Gradually, with the rise of impressionism, post-impressionism and symbolism the concern moved from perspective to the power of colour to evoke an almost hallucinatory experience only partly related to form; colour was itself symbolic. Later, in modernism, the subject largely disappeared altogether; the point of attention was often the flat surface of the canvas. A work of art referred primarily to itself.

Today, with the current revival in representational painting, a grasp of linear perspective remains an important skill in the artist’s hands. But, as with Fr Dougal's big and little cows, even its basic principles remain a mystery for many. 

(For a fuller review of the history and significance of perspective see Vincent Desiderio’s fine essay Towards an Allegorization of Method in The Figure: painting, drawing and sculpture, contemporary perspectives, edited by Margaret McCann, published by Skira Rizzoli in association with the New York Academy of Art.)