To realize such display that features appealing to human senses can be easily recognized by generating an illustration of point data, which shows a detailed shape interfered from an inputted term, in a ratio of deviation from corresponding points of an average shape.

A knowledge data base 7 stored in a memory 3a of a computer 3 is provided with an image data base 13 used for interference in a CPU 3b and is provided with a data base 11 of adjectives (evaluation terms) which evaluate impressions of vehicles, an average shape data base 15, and a detailed shape data base 17. When an adjective (evaluation term) expressing the image of a design is inputted from a keyboard 1, an illustration emphasized in a ratio of deviation from corresponding points of a category shape (an average of many same categories) corresponding to the inputted term by comparison with these corresponding points is outputted to a CRT 5. Another illustration where the degree of emphasis of the shape corresponding to each term is changed in accordance with user's request is outputted as a next candidate.