Vase-Face is a famous set of cognitive optical illusions developed around 1915 by the Danish psychologist Edgar Rubin. At first glance, you may see an image of a vase or a goblet. Look again and you see two human faces in silhouetted profile. The notNeutral interpretation of the illusion investigates the use of animated facial profiles as the negative images. The faces describe the following emotions: anger, joy, love, and defiance. The name of the set, "Conversation Piece", can be interpreted in several ways, just like the optical illusion. A conversation piece is an unusual object that arouses comment or interest. This refers to the vase depicted on the espresso cup and to the cup itself. The conversation is occurring between the two facial profiles, and also takes place between the espresso drinkers.