Until the launch of this series in 1985, the 15,000 volumes of the ancient Greek commentators on Aristotle, written mainly between 200 and 600 AD, constituted the largest corpus of extant Greek philosophical writings not translated into English or other European languages. Syrianus, originally from Alexandria, moved to Athens and became the head of the Academy there after the death of Plutarch of Athens. Syrianus attacked Aristotle in his commentary on Books 13 and 14 of the "Metaphysics," just as his pupil Proclus was to do later in his commentaries on Plato. This is because in "Metaphysics" 13-14, Aristotle himself was being thoroughly polemical towards Platonism, in particular against the Academic doctrine of Form-numbers and the whole concept of separable number. In reply, Syrianus gives an account of mathematical number and of geometrical entities, and of how all of these are processed in the mind, which was to influence Proclus and all subsequent Neoplatonists.

Syrianus, originally from Alexandria, moved to Athens and became the head of the Academy there after the death of Plutarch of Athens. This discussion of Aristotle's Metaphysics 3-4 shows how metaphysics, as a philosophical science, was conceived by the Neoplatonic philosopher of Late Antiquity. The questions raised by Aristotle in Metaphysics 3 regarding the scope of metaphysics are answered by Syrianus, who also criticises the alternative answers explored by Aristotle. In presenting Metaphysics 4, Syrianus explains in what sense metaphysics deals with 'being as being' and how this includes the essential attributes of being (unity/multiplicity, sameness/difference, etc.), showing also that it comes within the scope of metaphysics to deal with the primary axioms of scientific thought, in particular the Principle of Non-Contradiction, for which Syrianus provides arguments additional to those developed by Aristotle. Syrianus thus reveals how Aristotelian metaphysics was formalized and transformed by a philosophy which found its deepest roots in Pythagoras and Plato.