ABSTRACT
Objects in the environment exist in different locations. In turn, parts of objects take their place at different locations within an object, and parts themselves have spatial structure. A simple rule of nature is that no two objects can exist in the same location at the same time, and if they attempt to do so, there will be a rather substantial reconfiguration. Since the visual system evolved in this world and not in some other, it would be surprising if our perception of space and objects did not somehow reflect these natural principles. Even when overlapping figures are presented on the same plane, as in Figure 4.1, the visual system parses them into perceptual units in different spatial planes so that one unit is either perceived as in front of or behind the other. They are not in the same space in our mind’s eye even when they are in the same space on the page. The rules of perception are such that the perceptual world is isomorphic to the physical environment only as closely as is sufficient to support survival.
