Individual and group differences in susceptibility to various visual illusions have interested psychologists at least since Binet (1895). At present, there appear to be at least two more-or-less competing explanations of the ontogeny of illusion suscpetibility: Piaget\u27s (1969) Law of Relative Centrations and Segall, Campell and Herskovits\u27 91966) Carpentered World hypothesis. While these theories sometimes produce similar predications, they may also lead to contradictory ones
