11. PYTHAGORAEUS; otherwise SEXTIUS, SIXTUS, or XYSTUS. There is extant a little book of moral and religious aphorisms, translated by Rufinus into Latin, and probably interpolated by the translator, who is known to have been sufficiently unscrupulous in such matters, and who has admitted, in his preface to the work, that he had made certain additions from the advice of a religious father to his son, "electa quaedam religiosi parentis ad filium." The author is called by Rufinus in the preface, Sixtus; and Rufinus adds that he was identified by some persons with Sixtus, bishop of Rome and martyr; but it is to be observed that Rufinus does not express any opinion of his own as to their identity. Whether he meant Sixtus I., who was bishop early in the second century, and whose martyrdom is doubtful, or Sixtus II., who lived about the middle of the third century, and was certainly a martyr, is not clear. Origen, however, twice (Contra Celsum, lib. 8. c.30, and In Matt. torn. 15.3, vol. i. p. 763, vol. iii. p. 654, ed. Delarue) cites the s. Sententiae of Sextus (Γνῶμαι Σέχγου), as a work well known among Christians; but he does not mention either the episcopal rank or the martyrdom of the writer, whom, therefore, we can hardly identify with Sixtus I. And as Origen makes no reference to his being a contemporary writer, and speaks of his book as already in extensive circulation, it is difficult to suppose him to have been Sixtus II., whose elevation to the episcopate and martyrdom were a few years subsequent to Origen's own death. It is not clear whether Origen regarded Sextus as a Christian. Jerome cites the of Xystus (as he writes the name, Adv. Jovinian. lib. 1. c.49, and In Ezekiel. c. xviii. vs. 5, 6, seq.), enumerating him in one place among writers, all the rest of whom are heathens, and in the other place he expressly calls him a Pythagorean. In two other places he charges Rufinus with prefixing the name of a martyr and bishop to the productions of "a Christ-less and heathenish" (absque Christo et ethnici), and in another place, a "most heathenish " (gentilissimi) man (Hieron. In Jerem. c. xxii. vs. 24, 25, &c., and Ad Ctesiphont. 100.3, Epist. 43, ed. Benedict., 133, ed. Vallars.). Augustin, who had at first admitted the identity of the author of the Sententiae with one of the Sixti, bishops of Rome, afterwards retracted his opinion (comp. De Natura et Gratia, 100.77, and Retractat. lib. 2. c.42). Pelagius (apud August. Retractat. l.c.) appears to have admitted the identity, and a Syriac version, perhaps made from the Latin of Rufinus, which appears to have been extant in the time of Ebed-Jesu, A.D. 1300 (Assemani, Bibl. Orient. vol. i. p. 429), still bears the name of "Mar Xystus Episcopus Romae." Maximus the Confessor, in the seventh century (Schol. ad Dionys. Areop. Mysticam Theologiam, cap. 5, apud Opp. Dionys. vol. ii. p. 55, ed. Antwerp, 1634), applies to our Sextus the epithet ἐκκλησιαστικὸς φιλόσοφος, "Ecclesiasticus Philosophus ;" and Damascenus, in the eighth century (Sacra Parallela, Opera, vol. ii. p. 362, ed. Lequien), calls him Ζέζτου Ῥωμ., Zestus of Rome. Gennadius (De Viris Illustrib. 100.17) merely calls the work "Xysti Sententiae." In the ascribed to Pope Gelasius the work is mentioned as reputed to be by Saint Xystus, but is declared to be spurious, and to have been written by heretics. In the anonymous Appendix to the of Ildefonsus of Toledo, it is ascribed to Sixtus of Rome without hesitation. The testimony of the ancients as to the authorship is thus doubtful. An opinion mentioned by, and therefore older than, Rufinus (who was unjustly charged with fraud in the matter by his bitter enemy Jerome, and the charge has been repeated from age to age), ascribed it to Pope Sixtus, and the opinion was held by some persons, perhaps by most, in subsequent ages. Jerome appears to have first ascribed it to a heathen author; and Jerome's opinion, which would have had more weight but for his eagerness to fasten a charge of fraud upon Rufinus, was taken, perhaps without examination, by Augustin. Modern critics have been divided ; some (e. g. Siberus) retain the opinion which identifies the author with Pope Sixtus II.; others (e. g. Lequien, Not. ad Damascen. l.c.) regard the author as at any rate a Christian : but Gale, Mosheim, Brucker (Hist. Philos. period ii. pars i. lib. i. cap. ii. rect. 2.34), Fontanini (Hist. Litt. Aquileiensis, p. 302, &c.), to whom we have been much indebted, and Fabricius, identify the author with the elder Quintus Sextius (Quinti Sextii Patris), a Roman philosopher, mentioned with great encomiums by Seneca (Epistol. 64, 100.2). Seneca delighted much in a work of this Sextius, the title of which he does not give, but which he praises as written with great power. Quantus in illo, Dii boni, vigor est, quantum animi! Hoc non in omnibus philosophis invenies. Quorumdam scripta clarum habent tantum nomen, caetera exsanguia sunt. Instituunt, disputant, cavillantur, non faciunt animum quia non habent. Quum legeris Sextium dices, Vivit, viget, liber est, supra hominem est; dimittit me plenum ingentis fiduciae. In quacunque positione mentis sim, quum hunc lego, fatebor tibi, libet omnes casus provocare, libet exclamare, Quid cessas, Fortuna ? congredere ! paratum vides (ibid.). It is observable that Seneca speaks of Sextius as a Stoic in reality but not in name. From other Epistles of Seneca (59.6, 63.11, 13, 98.13, 108.17, and from his 2.36, 3.36) we learn that Sextius, though born of an illustrious family, had declined the dignity of senator when offered him by Julius Caesar ; that he abstained from animal food, though for different reasons than those ascribed to Pythagoras ; that he subjected himself to a scrupulous self-ex-amination at the close of each day; and that his philosophy, though expressed in the Greek language, was of Roman severity : --" Sextium ecce ... virum acrem, Graecis verbis, Romanis moribus, philosophantem." It appears that Sextius attempted, but in vain, to found a school of philosophy combining some features of the Pythagoreans with others of the Stoics; and which was consequently classed sometimes with one, and sometimes with the other of those sects. Seneca (Natur. Quaest. 7.32) says, "Sextiorum nova et Romani roboris secta, inter initia sua, quum magno impetu coepisset, exstincta est." " Xystus Pythagoricus philosophus" is recorded in Jerome's version of the of Eusebius as flourishing at the time of Christ's birth. He is also mentioned by Plutarch (De Profect. Virtut. Sentent. Opp. vol. vi. p. 288, ed. Reiske), and by the elder Pliny (H. Nat. 18.68, alibi).