WHY DOES THE PROXIMITY PRINCIPLE FAIL IN PERCEPTION OF MOTION?
The proximity principle is a fundamental fact of spatial vision. It has been a cornerstone of the Gestalt approach to perception, it is supported by overwhelming empirical evidence, and its utility has been proven in studies of the â€œecological statisticsâ€ of optical stimulation. We show that the principle fails in the perception of motion, which means that the standard (Minkowski) notion of proximity does not apply to the perceptual combination of space and time the way it applies to the combination of spatial dimensions in perceptual organization of static scenes. We demonstrate that in perception of motion the proximity principle should be supplanted by a more general notion â€“ the equilibrium principle â€“ which is related to the minimum principle championed by the Gestaltists.