ABSTRACT
One of the most obvious characteristics of the visual world is its stability. The world does not rotate as you turn around (you would become badly disoriented if it did) nor does it shoot from side to side or up and down as you shift your fixation from one object to another. This fact is so obvious that most of us take it as a matter of course and do not realize that there is any need for explanation. And yet it is really a very astonishing fact. Things possess a direction-from-here not with respect to the margins of the visual field but with respect to a fixed visual world—an external frame of reference which seems unexplainable on the basis of the retinal picture.
