 Iamblichus’ exegesis of the Categories (in particular his account of genera of hierarchical structures and his use of analogy) sheds light on other areas of his philosophy and forms the background of Iamblichus’ criticism of Porphyry’s account of divine hierarchy in the Reply to Porphyry (Chiaradonna 2018). There Iamblichus rejects Porphyry’s account of divine hierarchy as misleading, since Porphyry regarded classes of divine beings as species ranked under the same genus and determined by “properties” (idiōmata) that act as specific differentiae (Reply to Porphyry, I, 4 [SS-2013: 7.21–8.6]). In so doing, Porphyry ruins the very idea of hierarchy: divine comes to be a common genus which is predicated of all of its species, in the same way as animal is predicated of (say) horse and dog. Against Porphyry, Iamblichus calls for a qualified use of logical notions which makes the hierarchical relation between different classes of divine beings clear. Each level differs from the others as a whole and not in the same way as different species are divided under the same common genus. As said above, in his interpretation of the Categories Iamblichus argued that the genus is a hierarchical relation in which items from different levels are analogically connected to their origin. This can be set in parallel with what Iamblichus says in the Reply to Porphyry: 