 Boethus’ defense of the Categories documents that this treatise was intensely read and studied, and not only among philosophers friendly to Aristotle. The Stoic philosopher Athenodorus is credited with a book (Simplicius, In Cat. 86.22) or books (Porphyry, In Cat. 62.25–26) significantly entitled Against Aristotle’s Categories. We know very little about Athenodorus. If he is the same person as Athenodorus of Tarsus, who was a friend and adviser of the Emperor Augustus and was appointed by him as governor of Taurus, then Athenodorus was active in the second half of the 1st century BCE. There is no compelling reason to think that his critique of the Categories was written in the form of a commentary. Athenodorus could have been content with offering a series of objections and difficulties, just as the Platonist Lucius and Nicostratus would do more than a hundred years later (Simplicius, In Cat 1.18–20: “Others have chosen simply to present a series of difficulties (aporiai) arising from the text, which is what has been done by Lucius, and after him by Nicostratus, who took over for himself the job of Lucius”).