THE STIMULUS PERSPECTIVE    The
Empiricist and Gestalt theories
assume that the stimulus the
eye receives is inadequate,
ambiguous, or impoverished 
and thus cannot provide an
adequate explanation of our
perceptions. However,
researchers working in the
psychophysical tradition, the
third major theoretical
perspective, argue that all the
information necessary to
explain our perceptions is
present in the environment,
waiting to be picked up by the
moving eye of the observer. For
each type of perception--
whether it be of color, shape,
size, depth, motion, or 
whatever else--there is a unique
stimulus or type of stimulus
information. Thus there is no
need to postulate such
mechanisms as unconscious
inference or spontaneous
neural interaction to explain
perception.