In “Riverbed”, human backs in the photographs are quite thought-provoking, all of which come from pictures Tang found from the Internet. These retouched figures and the photoshoped stones push audiences to doubt about whether what you see is what you get. It also kind of explain why the backs were shaped as an identical and anonymous head in the paintings. The artist later painted them flatly and even built a head pyramid. The head turns to be a reflection of himself and fully reveals his latest contemplation and concern.