The procedure differed from that of traditional shape constancy experiments in that cues for the slant of the total frame‐surface containing the main figure, a shadow rectangle, were given. The impression of slant was determined by gradients of continuous perspective transformations caused by movable elastic material casting its shadow on a translucent screen. The following hypothesis was confirmed: the tendency to see a shape in its original proportions (i.e., those it has when shown in a frontal‐parallel orientation) increases with the increasingly strong impression of the slant of its plane surf