Aëtiana: The Method and Intellectual Context of a Doxographer (review)

In this book, the first of a projected series of volumes, Mansfeld and Runia have begun a massive investigation of the (mainly Greek) authors on whom we moderns rely for information about the numerous Greek philosophers whose works have not survived. The thousand-year tradition of Greek philosophy, extending from the Presocratics to Neoplatonism, is largely a story told via quotations, biographies, classifications, epitomes and criticisms. A few great works survive intact, including especially the dialogues of Plato, the technical writings of Aristotle, the sceptical books of Sextus Empiricus, and the Enneads of Plotinus; we also have most of the work on lost philosophers composed by such prolific authors as Cicero, Plutarch and Galen, and there are other well-known “sources,” such as the ten books of Lives and Doctrines, compiled by Diogenes Laertius. The present volume, however, deals with more recondite material: a work (P) on the physical doctrines of the philosophers, misattributed to Plutarch; a similar work, misattributed to Galen (G); the anthology of the Byzantine scholar Stobaeus (S); some chapters of Eusebius’ Praeparatio Evangelica (E); a work of Christian apologetics by the Syrian bishop Theodoret (T); and (in less detail) a few further writers from later antiquity.

What unifies this set of authors is the thesis put forward by Hermann Diels in his monumental Doxographi Graeci (1879), to the effect that all of them, directly or indirectly, are derived from a single work composed in about 100 CE by Aetius. According to Diels, Aetius derived his material from a much older collection (Vetusta Placita), and this, in its turn, was ultimately dependent on an extensive work by Aristotle’s pupil and successor, Theophrastus. Diels’ thesis, which underpins his collection of testimonia for the Presocratics (the “A” fragments of Diels/Kranz Vorsokratiker), has been the foundation of all subsequent work on the sources of fragmentary Greek (especially Presocratic) philosophers. Diels gave the name “doxography” to the genre of writing he took to be represented by Aetius and the authors of similar accounts of philosophical doctrines.

The volume under review explains, tests, supplements, and revises just that part of Diels’ thesis which invokes Aetius and the subsequent sources supposedly derived from this lost work. Mansfeld and Runia are uniquely qualified for this daunting task. Each of them has worked extensively on the historiography of Greek philosophy. As a Dutch duo in this volume, they bring unrivalled expertise to bear on revisiting the work of the formidable Diels.

The good news is that Diels’ Aetian hypothesis has been vindicated for the most part. Although the name Aetius is attested to by only Theodoret, Diels was quite right to deduce that Aetius’ compilation was the source of the material common to P, S, and T, and that E and G make extensive use of P. Hence scholars of ancient philosophy can continue to impose confidence in that part of Diels’ work which takes the story from Aetius into later antiquity. This finding means that the work of Mansfeld and Runia will hardly change one’s judgment concerning what can be known about the actual doctrines of fragmentary philosophers.

What it will particularly affect is one’s understanding of the lost Aetius himself and the surviving authors whose work is directly derived from him. The core of this book (primarily composed by Runia) is a set of chapters on P, S, and T, in which these three authors are studied for their own sake and their different methodologies carefully set out. Diels, under the influence of nineteenth-century philology, treated P, S, and T as if they were variant manuscripts rather than distinct authors. This misled him into regarding the doxographical tradition as much more uniform than it actually is. In earlier works both Mansfeld and Runia have greatly illuminated the dialectical and classificatory ways in which philosophical doctrines were...