The truth of the matter is that the principle underlying a classification can never be postulated in advance. It can only be discovered a posteriori by ethnographic investigation, that is, by experience.
The Savage Mind 58
Moreover, the “ethnographer cannot interpret myths and rites correctly, even if the interpretation is a structural one … without an exact identification of the plants and animals which are referred to or of such of their remains as are directly used.” (p. 46)
It is also important to explore substitutions. For example, the proper way to dot the eyes of an idol and bring the god to life requires blood from the comb of a white cock. In the absence of the cock, cinnabar ink dissolved in alcohol may be used instead, said my Daoist master. Red and _yang_ are, it appears, the essential distinctive features. The prototypical white cock, however, adds numerous additional associations: male, crowing to greet the rising sun, taking the place of the phoenix, the mythical bird associated with the South, the direction of fire, where _yang_ reaches its apogee in the diurnal cycle.
The lesson here is, once again, the importance of what Rex calls connoisseurship to analysis of symbols, in ads, I would add, as well as in rituals. Obsessive, geeky concern with detail is the very heart of the art. Without it, analysis spins off into vacuous generalities.