An anonymous commentary on book 2 of Aristotle's Posterior Analytics survives in Maximilian Wallies's edition, printed after John Philoponus in Commentaria in Aristotelem Graeca 13.3 (Berlin, 1909).
Wallies edited Philoponus on both books of the Posterior Analytics and appended this separate anonymous treatment of book 2. The compilation's date is uncertain; the edition does not assign a century. Book 2 is the book of definition, the middle term, and the search for the "what it is."
It is the Greek school-text for the problems of book 2 where Philoponus is not the only witness in the CAG volume. The commentary is anonymous; no philosopher's biography can be attached to it.
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