Perspective
The modern mind would do well to remember that perspective, such as that exhibited in paintings like Albrecht Durer's St. Jerome in His Chamber, was an historical invention and a product of the evolution of consciousness:
We must not forget that [in the Middle Ages] perspective had not yet been discovered, nor underrate the significance of this. True, it is no more than a device for pictorially representing depth, and separateness, in space. But how comes it that the device had never been discovered before--or, if discovered, never adopted? There were plenty of skilled artists, and they would certainly have hit upon it soon enough if depth in space had characterized the Collective Representations they wished to reproduce, as it characterizes ours. They did not need it. Before the scientific revolution the world was more like a garment men wore about them than a stage on which they moved. In such a world the convention of perspective was unnecessary. (SA 94-95)
Perspective is thus instrumental to the development of The Camera Sequence:
The eye, seeing in perspective, is projecting its own point of view, its punctiliar nothingness, as I would like to call it, into what geometricians call the plane at infinity but the ordinary man has to imagine as something like the inside of a vast hollow shell. By doing so, the eye converts that hollow sphere into a tableau that reduces depth to surface and flattens three dimensions into only two. That is the immediate experience so faithfully recorded by the camera. (RM 73)
See in particular "The Harp and the Camera" (RM 65-78), Saving the Appearances, Chap. XXII.