Porphyry’s Isagoge and Early Greek Neoplatonism

This paper focuses on Porphyry’s Isagoge against the wider background of debates about genera and the hierarchy of being in early Neoplatonism from Plotinus to Iamblichus. Three works are considered: Porphyry’s Isagoge, Plotinus tripartite treatise On The Genera of Beings (VI, 1-3 [42-44]), Iamblichus’ Reply to Porphyry (the so-called De Mysteriis). In addition to this, the discussion focuses on some passages on genus and predication from Porphyry’s and Iamblichus’ lost commentaries on Aristotle’s Categories preserved in Simplicius. In his account of genus, Porphyry draws on Aristotle and apparently claims that an amended version of the genus/species relation is able to express the hierarchy of different levels of beings. This view is different from that of Plotinus, who instead argues that intelligible and sensible beings are homonymous, as well as from that of Iamblichus, who rejects the existence of a common genus above intelligible and sensible beings, while emphasising the analogy subsisting between different levels in the hierarchy.