In 1975, John Dillon prefaced his book The Middle Platonists with these remarks: “The period in the history of Platonism which is the subject of this book has received hitherto comparatively little attention. It seems fated to remain in the position of those tedious tracts of the Mid-Western United States through which one passes with all possible haste, in order to reach the excitements of one coast or the other. In Platonism, likewise, one tends to move all too hastily from Plato to Plotinus.” While in recent years Europe has witnessed a growing interest in Middle Platonism, in North America many scholars are still passing by fast. Boys-Stones’s book will, I hope, persuade them to pause.
Is this, then, a book on “The Middle Platonists”? This is a question we must ask since Boys-Stones does use this notoriously problematic label. The problem with it is not so much that it leaves unclear what these thinkers were “in the middle of.” On most readings they were “in between” the end of the skeptical Academy and the beginning of the so-called Neoplatonist movement with Plotinus. The problem, rather, is that the label suggests that they were the only Platonists of the period that goes from the end of the first century BCE to the mid-third century CE. Since it is far from clear what it meant to be a “Platonist” at that time, or even what views could be defined as “Platonic,” it is general practice to lay down a set of beliefs widely recognized as “Platonic,” and to assess who the “Platonists,” or “Middle Platonists,” were in light of that. This procedure so far has led scholars to include among the Platonists of the period a Pythagorean like Numenius, and a self-declared follower of Moses like Philo of Alexandria, at the expense of Galen, and this despite the fact that, by and large, what Galen says in his work On The Doctrines of Hippocrates and Plato can be more easily traced back to Plato’s dialogues by contemporary readers than much of what one finds in either Numenius or Philo.
Although, at times, Boys-Stones seems to suggest that what he calls “Middle Platonism” just is the whole of Platonism in the relevant period, he is acutely aware of the problems raised by this assumption, and his book largely steers free of them. This is because it is not intended to be a book on the history of ancient philosophy, but on ancient philosophy itself. For the purposes of his project, Boys-Stones uses the conventional label “Middle Platonists” to refer to a group of thinkers tied together by what he calls a mere “family resemblance.” This family resemblance is determined on the basis of two criteria (pp. 8-9): 1) the adherence to the view that the ultimate explanatory causes of the cosmos are eternal and non- material, and 2) the conviction that Plato was always right. In light of these criteria, some philosophers who are traditionally viewed as Middle Platonists, like Antiochus of Ascalon, are excluded from the family, while others, who tend not to be viewed as such, like Galen, remain (mostly) excluded. Yet, insofar as there is indeed a family resemblance among the philosophers Boys-Stones groups together, I see nothing objectionable in calling them “Middle Platonists,” taking them to represent a sufficiently well-defined strand of what Platonism might have been in the relevant period. The second criterion used by Boys-Stones to circumscribe Middle Platonism might seem problematic. How are we to take these thinkers seriously as philosophers, one might wonder, if they were dogmatically convinced that Plato was always right? Boys-Stones argues that we should take their view that Plato was always right to express a certain way of interpreting the history of philosophy rather than a dogmatic commitment to Plato’s authority. The Middle Platonists, as he defines them, tended to consider agreement a mark of the truth, and viewed the Hellenistic schools (with the exception of the Epicureans) as different and contrasting attempts at correcting and developing Plato’s philosophy. To surmount the disagreement among those schools, they returned to Plato, on the basis of the “working hypothesis” that, if the truth about the world was to be found anywhere, it could only be found in Plato, where it first emerged complete and whole.
This explanation reveals the background against which Boys-Stones reads the Middle Platonists: Hellenistic philosophy. This is significant, because, on most readings, Middle Platonism is considered to be “a phase” in the history of Platonism. What I mean by this is that it is taken to be either a reaction to the skeptical Academy—and thus the continuation of a philosophical project that began within the Academy with Antiochus of Ascalon—or part of the so-called “perennial tradition of Platonism,” namely a system of thought that some scholars believe was developed by Plato and preserved by all subsequent ancient Platonists. For Boys-Stones, in contrast, Middle Platonism is a new movement that emerged primarily as a response to “the metaphysical materialism” (p. 8) of the Hellenistic schools. This seems, to me at least, exactly right, not least because it helps to make good philosophical sense of some prima facie obscure Middle Platonic theses, such as the thesis that matter is “The Indefinite Dyad.” Placed against the background of the Stoic conception of matter as unqualified body, this thesis appears to be a response to the Stoics rather than some kind of esoteric doctrine. In line with the philosophical approach of the book, the material is organized thematically rather than chronologically, and it is divided into three Parts, each of which deals with one of the parts of that whole system of the world the Middle Platonists thought they could find in Plato. Part I deals with cosmology, Part II with dialectic (i.e., epistemology and logic), and Part III with ethics (both what we might call “personal ethics” and politics). Each Part is divided into a number of chapters, and each chapter begins with a substantial essay on the topic under discussion, followed by notes and suggestions for further reading, and by a collection of relevant texts. The essays (examined below) provide a general introduction to the topic the texts deal with, and set the latter within the philosophical debate in which they can be most profitably read. The notes and suggestions for further reading offer a complete and exhaustive guide for those readers who wish to explore further. They provide a reconstruction of the status quaestionis on all the main topics examined in the book. This, in itself, is an invaluable service to the community of specialists and graduate students working in the field. The texts come from a large variety of sources, and many of them are fragments that were previously available only in French, German, or Italian translations.
Given Boys-Stones’ contention that Middle Platonism is a reaction to “the metaphysical materialism” of the Hellenistic schools, it is not surprising that Part I occupies well over half the book. Boys-Stones introduces the view that the world could not exist without non-material causes that are both external and prior to it as the “core” belief of the Middle Platonic family. This belief, he argues, is “core” not merely because it is shared in common by all the members of that family, but most of all because it grounds their approach to any philosophical subject, from cosmology to epistemology, to ethics. The discussion of cosmology is divided roughly into two sections. The first section (chapters 3-7) deals with “first principles” ( archai) and creation, while the second (chapter 8-12) examines the accounts of World Soul, individual souls, providence, and fate. Broadly speaking, the Middle Platonists posited three first principles: matter, Forms, and a creator god. What motivated them to posit these principles, according to Boys-Stones, was their criticism of the explanatory power of, on the one hand, the corporeal principles of the Stoics, and, on the other, the immanent forms of the Peripatetics. They argued against the Stoics that their corporeal principles required the same level of analysis and explanation as the bodies whose nature they were supposed to explain, while they remarked against the Peripatetics that immanent forms could only explain why bodies behaved the way they did, but not why this was best. Having set the Middle Platonists in dialogue with the main philosophical schools of their time, Boys-Stones introduces their accounts of the first principles by setting them in dialogue with each other. Rather than listing the views of individual thinkers (discussed in the notes), he offers a series of “models” according to which the first principles were conceived. The use of “models,” which persists throughout the book, not only makes the presentation tidier, but most of all helps the reader to focus on the philosophical motivations for each position. In the second section of the Part on cosmology (chapters 8-12), Boys-Stones offers a novel interpretation of the Middle Platonists’ accounts of the World Soul and of individual souls. No Middle Platonist, he argues, conceived of the World Soul as a first principle or cause of the cosmos nor viewed individual souls as substances existing in their own right without a body. They conceived of the World Soul, he maintains, as “a distributory mechanism” of empirical qualities, inherent in matter, and designed to coordinate, rather than to cause, the realization in it of the system of the Forms as a whole.
Part II, on dialectic (chapters 13-16), together with the first section of Part I (chapters 3-7), is in my view one of the highlights of the book. Against most interpretations, Boys-Stones argues that what the Middle Platonists found objectionable in empiricist theories of knowledge was not their account of concept-acquisition, but their perceived inability to provide a sufficiently stable foundation for knowledge. Having established this point, he examines the Middle Platonists’ accounts of syllogism and definition, and their methods of philosophical discovery, namely induction and analysis. Part II ends with an overview of Middle Platonic interpretations of Aristotle’s Categories (which includes a list of all the surviving Middle Platonic fragments on that work), and with an interesting analysis of the Middle Platonic conception of the hierarchy of the sciences (from dialectic and mathematics to what we might call “practical” or “applied” sciences, such as medicine). Part III, on ethics (chapters 17-20), discusses the ethical goal of “becoming like god” and the role of oikeiôsis in moral development. In contrast to most scholars, Boys-Stones argues that the goal of “becoming like god” should not be interpreted as an invitation to flee the world, but only to search for ethical values beyond it. He then goes on to explain the difference between Stoic and Middle Platonic accounts of oikeiôsis. Whereas for the Stoics oikeiôsis was a psychological mechanism which underpinned the entirety of our moral development, for the Middle Platonists, we read, it merely regulated the correct development of our non-rational impulses. At the end of the book, Boys-Stones examines a notoriously difficult text whose role in Middle Platonism has long been debated, the Chaldean Oracles. Rather than bringing the Oracles in direct dialogue with the Middle Platonic texts he has discussed, he provides a reconstruction of their system with a view to helping readers to assess for themselves their influence, if any, on Middle Platonism.
To conclude, Boys-Stones handles with painstaking precision and philosophical acumen an incredible amount of complex and controversial issues, without ever losing sight of the project as a whole. The result is an exciting and novel book. There are points on which I disagree with his interpretation. This is true, in particular, of his account of the World Soul and of individual souls. In contrast to him, I think the texts support the conclusion that the World Soul was, for the Middle Platonists, a first principle and cause of the cosmos, and individual souls were self-subsisting substances. These, however, are details, and it is a virtue of this book that it is meant to spark debate rather than to provide a neutral survey of the material.