Aristotle on Misperceiving

Suppose Socrates is looking at a bright red apple in good viewing conditions, so that it looks to him the colour it is. Schematically, Aristotle’s explanation of this “Good Case” is that the apple looks bright red to Socrates because he has taken on the perceptual form of bright red without the matter. But what happens if Socrates misperceives the apple instead and it looks purple? It is not at all clear how to apply Aristotle’s account of perception to such a “Bad Case.” Does Socrates still take on the perceptual form of the actual—bright red—colour of the apple in the Bad Case? Of purple? Neither? I argue that applying Aristotle’s account of perception to this sort of Bad Case requires that there are different ways of being in perceptual contact with perceptible qualities like the colour of an apple, depending on how that perceptual contact is mediated by changes in the sense organs and perceptual medium.