Abstract
In order to infer the component formal elements of impression from commercial goods and to clarify the process of formation of the impression in brain, experiments have been carried out using black triangles painted on white paper as a model of commercial goods. As the triangle was considered to be a characteristic model at the view point of a very few elements, it was investigated that a triangle formed the impression in higher level of layer structure such as beautiful or polished as a common recognition among many people. One figure of scalene or isosceles triangles was drawn on a sheet of white paper and the impression was sensory evaluated by means of semantic differential method. Experimental results showed that many people commonly recognized the high level impression depending on formal elements of basal length and angle even in a simple figure as the triangles. For reverse inference equations relating impression to the formal elements were derived and the triangles having the highest value in each impression items were decided.
