Henri Bergson is the name of the philosopher against whom the author, Gilles Deleuze launches his critical analyses. Bergson's theses are the names used to describe Henri Bergson's principles of movement in film theory. Bergson poses three theses beginning with the first thesis of movement and instant, followed by his second thesis of privileged instants and any-instant-whatevers, and ends with his third thesis of movement and change. The first thesis claims that movement is distinct from space covered. The second thesis claims there are two ways, ancient and/or modern, to reconstitute movement from an instant or position. The third thesis of movement is that movement is the change in duration or in the whole. Bergson is an important and main character in the text because Deleuze critiques his ideas and relates other characters to his viewpoint and cinematic expression. Husserl is the name of another philosopher who claims "consciousness" is "of" something compared to Bergson's claim that consciousness "is" something.