Evolution has adjusted the structure of the eye to the needs of life, resulting in a zonal structure of the field of view. The zones are independent channels of information. The forms seen are automatically separated on the retina of the eye. Classic architectural forms harmonize with the natural zones of the retina: the details of these forms precisely fill the zones, resonating with the preapprehension of an ideal form. The effect of overlapping the details of the seen form on the visual field zones evokes aesthetic feelings. All defini-tions of architectural structure are fuzzy: it is difficult to formulate them without using terms such as “part of a larger whole”. Each definition of an architectural detail must con-nect it with the entire building. The key to the concept of “detail” is therefore measure, the ratio of parts to the whole. The shape of the harp and the measurable string lengths pro-duce sounds in harmony with the melody of the soul. Does architecture – a specific instru-ment for triggering aesthetic emotions – also have “measurable string lengths”? Or maybe a detail of the building is a single string, the sound of which tunes the harmony of the entire architectural body? We won’t know until we don’t delve into the past by examining how the measurable properties of space evoke immeasurable emotions in us.23