Within the structure of every perceptual appearance or perceptual noema, defined as the thing perceived, only and exactly as it presents itself through a given act of perception, a distinction must be drawn. The distinction is between what actually falls under the senses and what, without being given in direct sense-experience, nonetheless plays an important role for the perception and the corresponding perceptual noema. When we look at a building from a certain standpoint so that we see the building from one of its sides, it is this side and its visual qualities, its color and shape, that fall under our senses.