Several styles of camerawork in Taxi Driver reveal Travis's loneliness and his distance from society. In general, the shots in Taxi Driver are slow and deliberate. After Travis applies to be a taxi driver, he walks out of the dispatcher garage, and as he does so, the camera pans from right to left across the screen as the cabs drive right, in the opposite direction. The other taxis seem to be going forward, in the direction we read and in the direction that picture narratives usually move. Travis walks the other way, and he is moving in the wrong direction even faster than the camera, so it takes a few moments for the camera to catch up to him. The shot indicates that something isn't quite right about Travis. Something about him isn't going the right way.
Much later, when Travis has begun his descent into psychosis, the editing reveals his disjointed state. As Travis turns toward the camera and his voiceover reads a section from his diary ("Listen you fuckers, you screwheads. . . . "), the scene suddenly stops and repeats itself. The cut is so abrupt that it seems like a mistake. The shots are close enough together that we can tell that the two takes are not different, and that the same shot is shown twice in a row. Travis repeats himself obsessively in the "You talkin' to me" speech, and here the film itself adopts that same method. The double shot shows that Travis does not repeat himself for practice, as we might, but that each time he erases what came before. Practice, by definition, involves improving on each additional effort, but Travis acts as if the previous attempts never happened. This editing technique of repetition and replacement gives us a glimpse into Travis's quickly plummeting mental state.
Scorsese has said he believes that the most important scene in Taxi Driver is the one showing Travis on a payphone in a hallway, trying to speak to Betsy. As this one-sided conversation takes place, the camera moves from Travis to a shot of an empty hallway around the corner. No people or motion fill the shot, and the hallway has no visual elements to attract the eye. This camera move prevents us from looking at Travis in his shame at losing Betsy, and the fact that neither participant in the phone conversation is visible conveys the fact that no real communication is taking place. The hallway suggests the path the film will take from this point on. Soon after this conversation, Travis changes from any lonely man to "God's lonely man," on a path toward what he views as his destiny—a path as straight and narrow as the hallway.