  In the bottom row of the diagram are three momentary perceptual experiences, registering the location of the pointer at three neighbouring times. For convenience, only a small selection of such experiences have been shown; we can suppose that in reality you enjoyed a distinct momentary experience for (at least) each discernibly distinct location of the pointer as it moved from the half-past position to the quarter-to position. The vertical column to the right depicts a single specious present, S. This has two sorts of component: a momentary visual experience of the dial-face (with the pointer at quarter-to); accompanying the latter (and co-conscious with it) are retentions of the earlier experiences, shown unshaded and in dotted outline. Again, only a few of the actual retentions are shown in the diagram: in reality there will be a retention corresponding to each of the momentary perceptual experiences you enjoyed during this brief interval. We are to suppose that your direct experience of change – in this case visible movement – takes place exclusively within these vertical structures.