Leo Goldsmith at the Not Coming to a Theater Near You website:
When Eadweard Muybridge began his series of proto-cinematic studies of movement in the late 1870s, he was already drawing upon science of human perception that had been around for at least forty years—albeit in reverse. Muybridge’s work was based on the notion that the movement of objects in space could be broken down into individual photographic frames, but already by the 1830s the zoetrope and phenakistoscope (whose name means “to deceive the viewer”) proved that flat images assembled linearly viewed rapidly in succession could create the illusion of moving objects. While a photographer like Muybridge used this science to study the movement of animals in single moments in time, mathematicians and physicists like Joseph Plateau and George Horner were already using drawing and painting to create small, narrative illusions.
This is to suggest that not only is animation an important part of what we now call cinema, one that predates and predicts it, but that it is perhaps even the very basis of film.