Parts of Recognition
A complete theory of object recognition is an impossibility ??t simply because of the multiplicity of visual cues we exploit in elegant coordination to identify an object, but primarily because recognition involves fixation of belief, and anything one knows may be relevant. We finesse this obstacle with two moves. The first restricts attention to one visual cue, the shapes of objects; the second restricts attention to one problem, the initial guess at the identity of an object. We propose that the visual system decomposes a shape into parts, that it does so using a rule defining part boundaries rather than part shapes, that the rule exploits a uniformity of nature ??ransversality, and that parts with their descriptions and spatial relations provide a first index into a memory of shapes. These rules lead to a more comprehensive explanation of several visual illusions. The role of inductive inference is stressed in our theory. We conclude with a pré£©s of unsolved problems.