James J. Gibson laid out a plan for an ecological theory of film perception. Film cameras were not designed with a thorough understanding of how human perception functions. As the technology developed, the filmmakers learned very quickly that the movements of the clay figures appeared jerky, particularly when they were supposed to be moving at higher speeds When considering how humans observe films, it is important to draw a firm distinction between two perceptual phenomena: illusion of motion and flicker fusion. After the actors have completed their scene, but before the audience can watch a finished film, editing takes place. In addition to dialogue and music, the majority of films include sound effects. While proper sound balancing would ensure that these sounds would be quiet, it would also make sure they were not absent. Symbols and symbolism can be described as the arbitrary assignment of meaning to something, such as objects, events, or sounds.