Notice that in face E , the eyelid has also moved. In terms of the semiotic model facial expressions operate as indexes . That is, they are directly connected to the emotions of the individual. Because of this, they are extremely powerful tools for communication. For example, as the next quotation points out, eye contact alone possesses considerable complexity.
Most encounters begin with eye contact.
Nevertheless, as Goffman has pointed out, once an American has allowed another to catch his eye, he's held to be open to whatever follows. That's why waitresses develop such skill at not allowing their eyes to be caught when they're particularly busy. Children learn this particular function of eye contact very early. As an example, consider the next set of faces in which the shape of the eyebrows, the shape of the eyes, and the shape of the mouth are all subject to change. The range of possible meanings is much larger than it was in the previous example.