This much, however, does not explain how perception occurs. Aristotle claims that perception is best understood on the model of hylomorphic change generally: just as a house changes from blue to white when acted upon by the agency of a painter applying paint, so “perception comes about with <an organ’s> being changed and affected … for it seems to be a kind of alteration” (De Anima ii 5, 416b33–34). So in line with his general account of alteration, Aristotle treats perception as a case of