抄録
Geometrically projected perspective represents a well-constrained problem, but does not always produce a visually correct result. However, perspective by eye requires judgement and is not well-constrained. This represents the dichotomy between geometric logic and perception. A hypo-thesis on this division was investigated by an experiment in which 14 college students were asked to construct six images of a cube using a CAD programme. The results showed that subjects tended to construct the less visible side longer, and conversely, the more visible side shorter, than geometric perspective would produce. Moreover, more acute the angle, the larger the individual differences become.