Several observations about the way humans conceive of attributes, changes, and covariation of stimuli are presented as indications for the existence of a conceptual hierarchy of dimensions in which time dominates space, and space dominates every other dimension. (Author)

Piaget's theory of space perception is presented in the format of a hypothetico-deductive system. Eleven hypotheses regarding infants' space perception are defined, and Piaget's evidence for each is summarized. Presuppositions underlying the arguments are explicated. Critical notes are inserted and general conclusions are briefly discussed.…