First, what is it that we perceive? We perceive things — configurations against a background. From time to time, it is true, perceptions of the light, or the darkness, or fog, or sky, or rumble, or stench get mentioned in Merleau-Ponty's text, but they are perhaps moments of instability, or inachievement, not the normal case. For Merleau-Ponty finds there is such a thing as a norm, a finality, in perceptual consciousness; it is the positing of things. The phenomenon of perceptual constancies, of a sense of the real colors, the right lighting, the true size and shape, shows that there are norms within the perceptual flux; what determines the real and the true and the right is the possibility of a thing taking form. And the compossibility of things — there is a coherence, a consistency in the flowing field of perception; it is a world of coexisting, compossible things. That is why, despite the fog, despite the darkness, despite the rumble, Merleau-Ponty can say that a figure against a field is the essence of, the very definition of consciousness. We cannot explain the apparition of things by a subject of the perception which collates or synthesizes its sensations; it is rather the thing that polarizes and focuses and synthesizes the various surfaces and senses of the perceiving subject.