ABSTRACT
The visible world is furnished with objects. These may be large or small, rough or smooth, rigid or flexible, and moving or still. Objects. are en~ countered in shapes of limitless variety, arranged on surfaces in infinitely many possible configurations. But as adults, we nearly always perceive each object as unitary, as separate from the surfaces around it, and as persisting over time. Our ability to do this is intriguing, for the boundaries of an object are rarely preserved, in any direct way, in the structure of light at the eye.
