 All that was left at this point was to establish harmony between different authors; and this is where sumphōnia or “agreement” comes into play. Building on Porphyry’s efforts (as opposed to Plotinus’ views), Iamblichus fully integrated Aristotle into Platonism (see  Section 5  below); he also took into account Pythagoras and the pseudo-Pythagorean corpus (see  Section 4.3).  References to other schools are scarce and mostly critical. Iamblichus’ philosophical authorities, then, are Plato, Aristotle, and the Pythagoreans; they were complemented by several texts held to be divinely inspired, of which the two most important ones are the Chaldean Oracles (a second-century collection of verse oracles which provide a Platonic-influenced revelation mostly based on the Timaeus, and which develop a dualistic view about matter and a divine energy called “fire”) and the pseudo-Orphic Rhapsodies in 24 books. The Chaldean Oracles at least are known to have been commented upon by Iamblichus, in a huge commentary comprising at least 28 books (Damascius, De Principiis II, 1.5–8). (on Iamblichus’ religious views, see below,  Section 6.3.)