Peirce shows how he presupposes that a 'most general science of semeiotic' is entirely a miatter of culture. Semiotics unfolds even beyond the debate on specific differences between nature and culture. That insight leads not only to linguistic but also to other expressive phenomena, among which the human body. Faces are perhaps the most outstanding bodily carriers of signs and expressions, so that Peirce's analyses of Thirdness relate to the human face not as a natural, but as a cultural datum, in particular an artifice. The cases in this chapter show how the human face is an artifice and how realities can appear to be fictitious within patterns of semiotic nature. Any sign can thus be a correlative to a fictitious world.