 This is a constitutive claim: perception doesn’t merely depend on mental imagery causally, it depends on mental imagery constitutively. This, like all constitutive claims, is a fairly strong one, and a much more modest, also historically influential, pre-Kantian, view dominant among, for example, the British empiricists, would be that perception does not depend on mental imagery at all, of if it does, it depends on it merely causally. While there has never been an explicit debate between these two positions, recent empirical research helps us to assess the respective merits of these two ways of thinking about the relation between perception and mental imagery.