The core content of culture is a set of specific recurrent optional features, hard-wired into nature, and into subconscious behaviour; measurable in artworks, built sites and alphabets; and testable against about 100 details of an inter-dependent structure of five layers. Archetypal features always appear in a specific spatial peripheral sequence; with an axial grid between the eyes or focal points of specific pairs of opposites. Structuralist anthropology is a viable science, despite its recent distractions due to politics and academic trends.
Five layers of subconscious perception and expression are visible in artworks and built sites. The layers are: (a) Type characters with specific optional features; (b) type sequence, clockwise or anti-clockwise; (c) axial grid between eyes or focal points of opposite pairs of types; (d) three pairs of polar junctures, implying three planes of expression; (e) orientation of polar pairs vertical or horizontal to the ground-line or a cardinal direction, co-incidental with the seasonal time-frame of the local culture. Types could be labelled after any natural or cultural set, such as species, myths or months. Generic labels, such as social functions, avoid the false impression of diffusion from one particular medium or culture.