 The treatises under Archytas’ name collected in Thesleff 1965 have been almost universally regarded as not by the historical Archytas, except for On Law and Justice, where there has been considerable controversy. Most are only preserved in fragments, although there are two brief complete works. The most famous of these pseudepigrapha is Concerning the Whole System [sc. of Categories] or Concerning the Ten Categories (preserved complete, see Szlezak 1972). This work along with the treatise On Opposites (Thesleff 1965, 15.3–19.2) and the much later Ten Universal Assertions (preserved complete, first ascribed to Archytas in the 15th century AD; see Szlezak 1972) represent the attempt to claim Aristotle’s doctrine of categories for Archytas and the Pythagoreans (see also Griffin 2015). This attempt was to some extent successful; both Simplicius and Iamblichus regarded the Archytan works on categories as genuine anticipations of Aristotle (CAG VIII. 2, 9–25). Concerning the Ten Categories and On Opposites are very frequently cited in the ancient commentaries on Aristotle’s Categories. Pseudo-Archytas identifies ten categories with names that are virtually identical to those used by Aristotle, and his language follows Aristotle closely in many places. The division of Archytas’ work into two treatises, Concerning the Ten Categories and On Opposites, reflects the work of Andronicus of Rhodes, who first separated the last six chapters of Aristotle’s Categories from the rest. Thus, the works in Archytas’ name must have been composed after Andronicus’ work in the first century BC. Other pseudepigrapha in metaphysics and epistemology include On Principles (Thesleff 1965, 19.3 – 20.17) and On Intelligence and Perception (Thesleff 1965, 36.12–39.25), which includes a paraphrase of the divided line passage in Plato’s Republic. Mansfeld has recently shown that Fragment 1 of the latter work in Thesleff’s collection belongs to the former work (Mansfeld 2019). De Cesaris and Horky (2018) provide commentary on On Intelligence and Perception, but much remains obscure in this difficult work. Mansfeld (2019) shows that On Intelligence and Perception is not likely to have been an influence on the account of Pythagorean principles in Aetius Placita 1.3.8 as has been suggested by De Cesaris and Horky (2018). Ulacco (2017) establishes new texts (with commentary) for On Principles, On Intelligence and Perception and On Opposites. Further metaphysical and epistemological works include On Being (Thesleff 1965, 40.1–16) and On Wisdom (Thesleff 1965, 43.24–45.4). The authenticity of this latter work has recently been defended on the grounds that its admitted similarities to passages in Aristotle are a result of Archytas’ influence on Aristotle rather than an indication that the work was forged on the basis of Aristotle (Johnson 2008, 193–194). It is indeed true that Aristotle devoted several lost works to Archytas and must have been familiar with his thought. However, the issue of authenticity within the Pythagorean tradition has a different character than is the case with other ancient authors. In the case of an author such as Plato, where the vast majority of surviving works are surely authentic, the onus of proof is on anyone who wants to argue that a work is spurious. In the Pythagorean tradition, on the other hand, where surely spurious works far outnumber genuine ones, the situation is reversed. The onus of proof rests on anyone who regards a Pythagorean work as genuine to show that it does not fit the pattern of the forged Pythagorean treatises and that its contents can be corroborated by evidence dating before the third century, when the Pythagorean pseudepigrapha start to be generated. Since On Wisdom does share with the pseudepigrapha the characteristic of using important Aristotelian distinctions (Huffman 2005, 598–599), even if it is not as blatant a copy of Aristotle’s ideas as the works on categories ascribed to Archytas, it is much more likely that it was forged on the basis of Aristotle than that Aristotle is using On Wisdom without attribution. In order for the latter situation to be probable there would need to be fourth-century evidence independent of On Wisdom which ascribed the ideas found in it to Archytas. Horky 2015 includes On Wisdom among the pseudepigrapha and provides analysis of it. For recent discussions of the nature of the pseudepigrapha ascribed to Archytas see Bonazzi 2013 and Centrone 2014. For the nature of the appropriation of Aristotle in pseudepigrapha ascribed to Archytas and other early Pythagoreans see Ulacco 2016.