The Discovery of Linear Perspective in the Renaissance
The laws of linear perspective were discovered in Italy during the Renaissance, from an interest in the visual illusion that had developed in Umbria from the 13th Century.
Perspective puts the viewer at the base of pictorial construction, just as emerging humanism places man at the center of philosophical reflection.
It was the architect Filippo Brunelleschi who first promotion the conical perspective in 1425, using the Baptistery building in Florence as an example. On the reverse of a wooden tablet pierced with a hole for the eye, he painted the facade of the Baptistery of Florence; in its upper part, he fixed a polished metal plate which reflected the sky. The spectator must then stand in front of this tablet and look out of the hole, holding a mirror in front of the representation on the reverse. Thus, the spectator can see, in the upper part, the building (which is really located behind him) and in the lower part, the drawing of the Baptistery which is superimposed on the real building, in an illusion of a unique continued space.
Following him, the Italian painters perfected the system of pictorial techniques to represent the three dimensions of an object or a scene by an image on a flat surface. In Germany, Albrecht Dürer explored the space put into perspective by means of drawing and painting, in an important treatise entitled "Instruction on Measurement, with compass and ruler, in lines, planes, and whole bodies", published in several editions in Nuremberg from 1525 which he illustrated with numerous drawings explaining the construction of perspective.
This is how the Renaissance man invented the linear perspective that shaped our current conception of space.