For Aristotle, colors and other perceptibles are a feature of the external environment around us, which can exist independently of being perceived. They are not subjective features of our experiences, but objective features of objects. They appear to us, moreover, at least in the most basic cases exactly as they are. Perception reveals just what colors, understood as first actualities, are like on their own and similarly for odors, flavors, tones, and the rest. This is what Aristotle’s direct realism and his realism about perceptible qualities allows him. At the same time, he maintains that we have a peripheral awareness of our own perceptual awareness, which is perceptible in a way that is directly related to the perceptible quality that produced it. Our perceptual awareness of our seeing a color has a distinctive quality that is determined by the color, because of the way it causally affects our visual organs. But this distinctive quality is conceptually posterior to the external quality that appears to us in perception and which determines its character. In describing the quality of our perceptual experience we are inevitably forced to describe it in terms of the characteristic qualities of the objects themselves. Which, Aristotle thinks, is as it should be. 

Victor Caston is a Professor of Philosophy and Classical Studies at the University of Michigan, Ann Arbor, and Editor of Oxford Studies in Ancient Philosophy. He has written extensively on Aristotelian philosophy of mind and is currently working on a book, The Stoics on Mental Representation and Content.