Philosophy Study, April 2021, Vol. 11, No. 4, 293-302 doi: 10.17265/2159-5313/2021.04.005 D D AV I D PUBLISHING Diogenes Laërtius: A Moderate Skeptic in the History of Philosophy (Book IX)∗ Ramón Román-Alcalá University of Córdoba, Córdoba, Spain This paper presents the keys and reasons for Diogenes Laërtius’ alleged scepticism, based on an analysis of the general design of his work The Lives and Opinions of Eminent Philosophers. I believe that it would be manifestly erroneous to seek confirmation of this scepticism solely in Book IX without taking into account the overall structure of the work. A convincing explanation is also provided of one of the most enigmatic and most studied phrases in this work. What did Diogenes mean when he said that Apollonides of Nicaea was ὁ παρ’ ἡμῶν (“one of us”)? Keywords: scepticism, Diogenes Laërtius, sextus, Pyrrho, The Lives of Philosophers The Singular Book IX of “The Lives” Diogenes Laërtius’ work Lives and Opinions of Eminent Philosophers was already relatively well-known in antiquity, due not only to the author’s popularity but also to the singularity of the work, in which he had succeeded in faithfully characterising much of ancient historiography. Moreover, and this is important to highlight in our introduction, taking into account the structure of many of the books and sources mentioned by Diogenes, this work began a new and highly original historiographic genre, which could be called “successions”. Diogenes’ Lives of Philosophers is a singular work. It starts with an introduction focusing on the origins of philosophy (which were undoubtedly Greek), the different classifications of philosophy and philosophers. The author then presents two series of philosophers, as two starting points of philosophy: one starting with the Seven Sages or Wise men and ending with the Stoics, and including Socrates, Plato and Aristotle (Books I-VII), which Diogenes called the Ionian school, since Thales was the first recognised philosopher and came from Ionia; and another series that started with Pythagoras and ended with the Sceptics and Epicurus, followed by Heraclitus, Xenophanes, Parmenides or Democritus, among others, and which he referred to as the Italic school (Books VIII-X). In all the books or explanations of philosophical schools, he mentions philosophers who lived up to the first century B.C., except in the succession of the sceptics, in which he mentions authors up to 200 A.D. Therefore, each book is unique and different in terms of its structure and philosophical and literary references. This means that Diogenes used a series of different materials and sources. In addition to the authors’ ∗Acknowledgement: Article is a deliverable of the Research Project I+D+i FFI2016-32989 on skepticism financed by the Ministry of Economics and Competitivity. Ramón Román-Alcalá, Ph.D., professor, Department of Social Sciences and Humanities, University of Córdoba, Córdoba, Spain. 294 DIOGENES LAËRTIUS: A MODERATE SKEPTIC IN THE HISTORY OF PHILOSOPHY biographies, there are collections of sayings, lists of works, lists of documents, information on dubious traditions, etc. All this information confirms, without a shadow of doubt, that Diogenes’ work could not have been based on a single source with new information introduced by the author. In our opinion, Book IX is one of the most complex books. It contains exceptional data and mysterious, original, and unusual references that make it one of the most challenging books in the entire work. Book IX mainly reviews most of the succession of philosophers presented by Diogenes in Book I (pp. 13-15), between Pythagoras and Epicurus1. As mentioned previously, Diogenes described two philosophical schools: the Ionian school, which was founded by Thales; and the Italic school, founded by Pythagoras. Between the life of Pythagoras described in Book VIII and that of Epicurus in Book X, the philosophers included in the Italic succession in the preface are described in Book IX. However, the list of authors in Book IX includes more than those mentioned and presents very disconcerting aspects and certain selections of philosophers that are initially unexplainable. So, with this article, I want to try two ideas: One is that Diogenes provides evidence of a moderate scepticism in his most famous book; the other is that we can only affirm this, if we look at the general structure of the work and not only the Book IX, where the skeptics appear. The Successions of Philosophers: Formulae Clarifying Philosophy If the general line of succession described by Diogenes in Book I, 15, is, broadly speaking, common to the list of authors that appears in Book IX, there are certain specific aspects that differ from the Italic succession of philosophers, presented in the preface, which may provide some clues as to the reason for this strange selection. The first striking aspect is that Heraclitus is included among the Pythagorean philosophers mentioned in Book VIII and the Eleatics in Book IX, although he traditionally does not appear linearly in any succession of these philosophers (Román-Alcalá, 2012a). Furthermore, Heraclitus and Xenophanes share one characteristic that distinguishes them from the other philosophers (οί σποράδην), namely that they do not belong to any school. It is also interesting that Diogenes of Apollonia appears between Protagoras and Anaxarchus. Many authors believe that this is an error and that Diogenes Laërtius confused Diogenes of Apollonia with Diogenes of Smyrna (D.L. IX, p. 58)2. However, I believe that he is included here deliberately3 because Diogenes of Apollonia, whose doxography derived from Theophrastus, was a key figure in the history of scepticism. And, lastly, but most importantly, it includes the sceptic philosophers Pyrrho and Timon. I have already argued elsewhere (Román-Alcalá, 2007) that for Pyrrho’s contemporaries the only viable scepticism was that of the Platonic Academy (Clayman, 2009). That is to say, there would be “Pyrronians” in that they follow the teachings of Pyrrho, but not “pyrrhonics” 4 in the sense of forming a school or philosophical movement with a certain doctrine. The great mistake of Antiochus, the last head of the platonic academy, was to transform the Platonic Academy into dogmatic Stoicism, which forced Aenesidemus, who was a disciple of the sceptical platonic academy, to search for a new origin of skepticism (in Pyrrho of Elis) and recover the sceptic line abandoned in the academy. In this context of recomposition of scepticism, Diogenes 1 This is the basic thesis supported by Decleva Caizzi (1992, pp. 4218-4240). 2 For example, Hicks (1925, pp. 184-185) believes this confusion exists. 3 Cf. Decleva Caizzi (1992, p. 4220; Laks, 1983, Appendix 4, pp. 258 et seq.); also see the translation by Gigante (1962, p. 564, Note 192). 4 There are doubts about the unequivocal reality of a radical Pyrrhonic school, see Román-Alcalá (2012b, pp. 111-130), in this article defending its invention as a school, group or sect and the reasons for this invention by Diogenes Laërtius. DIOGENES LAËRTIUS: A MODERATE SKEPTIC IN THE HISTORY OF PHILOSOPHY 295 Laërtius wrote Book IX. Therefore, in my opinion, the key for understanding this book lies in his development of scepticism5 and his direct affiliation with the Abderites and some pre-Socratics. The most important part of this book therefore focuses on Pyrrho’s relationship with the philosophy that preceded him. In this section, Diogenes claims that Pyrrho’s scepticism developed due to the influence of Anaxarchus, a pupil of Democritus (D.L. IX, pp. 58, 61, 72, 107). This surprising affirmation is interesting because although Democritus and Anaxarchus inspired Pyrrhonian philosophy according to Diogenes, they also belonged to a strong Pre-Socratic tradition. Thus, in this book, Diogenes groups the following thinkers: Heraclitus, Xenophanes, Parmenides, Melissus, Zeno, Leucippus, Democritus, Protagoras, Diogenes of Apollonia, Anaxarchus, Pyrrho, and Timon. Diogenes Laërtius’ reasons for including all these philosophers in Book IX or in other books are unclear. However, it is likely that Diogenes grouped authors with similar lines of thought. If this was the case, then authors, such as Heraclitus, Xenophanes, and Parmenides must have had something in common: They started, according to Diogenes, a type of philosophy that was developed by Democritus and Protagoras and culminated in Pyrrho. I maintain the hypothesis that Diogenes grouped in Book IX all the authors who shared a common concern for knowledge, which, after different developments, culminated in Pyrrhonian scepticism. This idea could seem strange if there were no other evidence to confirm it. Examples of texts that mention this group of philosophers at the same time as Diogenes Laërtius show that was not an anomaly but a sequence. We will start with a text by Clement of Alexandria in his Stromata, XIV I 64, 2-4, in which he writes: Xenophanes of Colophon was the founder of the Eleatic school. Parmenides was the disciple of Xenophanes, and Zeno of him; then came Leucippus, and then Democritus. Disciples of Democritus were Protagoras of Abdera and Metrodorus of Chios, whose pupil was Diogenes of Smyrna; and his again Anaxarchus, and his Pyrrho, and his Nausiphanes. Some say that Epicurus was a scholar of his. (Clemente, Strommata, I, XIV, 64, 2-4: DK 21 A 8: Decleva Caizzi, 25 A)6 Significantly, this text of Clement, which, as in Diogenes’ work, ranges from Xenophanes to Pyrrho, is also supported by Eusebius of Caesarea, albeit with certain differences. In one noteworthy text, he writes: A disciple of Xenophanes was Parmenides, and his Melissus, and his Zeno, and his Leucippus, and his Democritus, and his Protagoras and Nesa, and his again Metrodorus, and his Diogenes, and his Anaxarchus. And a companion of Anaxarchus was Pyrrho, who founded the current (discourse) of the so-called skeptics. (Eusebio de Cesárea, 1843, pp.