The current status of the size-distance hypotheses.

In the history of the psychology of perception few matters have been of more continuous interest than the relationship between perceived size and perceived distance. It is our objective to examine the current status of this question by reviewing the recent literature. With some exceptions our review will be confined to investigations which have been reported since 1952. Several surveys of the literature prior to 1952 are available, and for this reason we will have relatively little to say about these earlier investigations (reviews can be found in Boring, 1942, Ch. 8; Vernon, 1954, Ch. 5; Woodworth & Schlosberg, 1954, Ch. 16). Most studies of this question have converged upon a single proposition which aptly has been called the SizeDistance Invariance Hypothesis. The invariance hypothesis is often stated in the following terms: "A retinal projection or visual angle of given size determines a unique ratio of apparent size to apparent distance" (Kilpatrick & Ittelson, 1953, p. 224). This proposition has been applied