Abstract

The republication of a classic article by Gaetano Kanizsa, originally published in 1968, is introduced. Kanizsa addressed Musatti's argument about the impossibility of a crucial experiment on autochthonous vs. empirical factors of perceptual organization and produced a series of demonstrations on object formation, depth stratification, form, and motion. The actual immunity of Kanizsa's demonstrations to Musatti's criticism is evaluated, also taking into account the present literature on the cognitive (im)penetrability of perception.