BMCR 2022.02.11

Plato’s sun-like good: dialectic in the Republic

, Plato's sun-like good: dialectic in the Republic. Cambridge; New York: Cambridge University Press, 2021. Pp. x, 240. ISBN 9781316516874 $99.99.

In an early and important article, which she published as Sarah Waterlow, the late Sarah Broadie (1941-2021) wrote: “our concern is less with what Plato the individual may himself have meant, than with what his theory means.”[1] A characteristically resolute and praiseworthy determination to pursue the practical implications of the Idea of the Good in Plato’s Republic—to explain its meaning in practice—continues to distinguish Broadie’s last book almost fifty years later. The fact that it is, by a tragic necessity, her last book, may be strictly speaking irrelevant to a critical examination of its contents but no restriction of this kind will be applied here. So strong is the amiable impression made by the author’s seriousness of purpose, and so impressive is this culminating effort to come to grips with Plato, that an attempt to avoid the memorial element would be misplaced. Since Sarah Broadie is no longer with us, we can profitably turn to this bold and elegant last word as a way of keeping her spirit alive, allowing the benign force of her scholarly persona to live on as an inspiration to our own practice as students of ancient philosophy quite apart from any theoretical objections one might have with respect to what Plato himself may have meant by the Idea of the Good. If the purpose of a good review is to encourage others to read the book being reviewed, this one will rather attempt to continue the dialogue that this book initiates, and it is addressed primarily to those who will have read Broadie’s last book, for every student currently studying Plato’s Republic will need to read it.

Broadie is fully aware of the unorthodox and indeed revolutionary nature of her thesis: that the Idea of the Good cashes out as the form of what she calls “the G-question,” as when the ideal rulers of Callipolis apply the question “is it good?” to any conceivable implementation of justice and the other virtues in their actual practice of ruling. She calls this conception of the Good “interrogative,” and she defends it with spirit, dialectical skill, and erudition against more theoretical and traditional accounts. Once the philosophical rulers have been habituated by ten years of mathematical studies to rise above their passions, it is the dialectic engendered by habitually raising the G-question as an ongoing test that will cause the forms of the virtues, as applied to concrete empirical circumstances, to be known in practice. It is in this way that the Idea of the Good becomes “sun-like,” causing the other forms to become knowable. Throughout, Broadie illuminates the highly imaginative image of the sun in Republic 6 with her by no means implausible way of imagining the actual practice of the city’s guardians while implementing the education they are said to receive in Republic 7. Fleshing out the sun-like good by means of what the rulers of Callipolis would actually need to do while ruling creates a kind of hermeneutic hylomorphism, characteristically Aristotelian in spirit, and yet completely fresh and original in practice.

Broadie’s book is divided into five parts of which the second (“The Form of the Good and Knowledge”), divided into twenty-one sections, is by far the longest and the most argumentatively dense. It is followed by three shorter parts which may best be described as dialectical. The third (“The Form of the Good and Being”) is the most philological in the book, and deploys an emphasis on the verb προσεῖναι at Republic 509b to illuminate the shortcomings of more traditional accounts of the Idea of the Good as sun-like, to which accounts she is characteristically generous. The dialectical mode continues in Part Four (“Various Further Questions”) in which she defends, with logical rigor and argumentative acuity, the interrogative account of the Good she has offered in Part Two. Finally, in a concluding part called “Winding Up” (206-25), Broadie briefly recapitulates and analyzes her complex argument into twenty-one numbered stages or claims. While her book’s subject is how dialectic functions in the actual practice of the ideal rulers of Callipolis, its meaning is better understood in relation to Broadie’s own use of dialectic: it is in her own scholarly method as practiced throughout the book and emphasized by the structure of its last three parts that makes her work exemplary and inspiring.

These methods deserve both elucidation and imitation. To begin with, this book is refreshingly but also essentially up-to-date. Decisive interpretive decisions rest on her encounters with recently published work in a variety of traditions, and her footnotes are models of generosity and benign critical acumen. Striking as well is the abundant evidence of collegiality, especially with respect to Barbara Sattler and Alex Long, her younger colleagues at St. Andrew’s. The alleged dialogues arising from the G-question as posed and answered by the imaginary rulers of Callipolis are the merely shadowy counterparts of far more easily imagined dialogues arising from Broadie’s own thoughtful consideration of the views of her colleagues and other scholars actively publishing in the field. In addition to evidence of lifelong dialogues with Christopher Rowe, Myles Burnyeat, and Malcolm Schofield, she displays remarkable deference to Mario Vegetti—this doubtless contributes to her realism as applied to the actual workings of Callipolis—and repeatedly addresses the views of the Tübingen School. In short, it is her own scholarly practice of literary and personal dialectic that will keep Broadie’s memory green for those who remain sensible, as we should, of our collective loss.

In between the Sun image and the dialectical education of the guardians stand the Divided Line and the Allegory of the Cave, and it is her approach to the former in the book’s second part that constitutes her principal contribution on a theoretical level. Incorporating the content of her 2020 Aquinas Lecture on “Mathematics in Plato’s Republic” at Marquette University, Broadie sounds the keynote of her approach to distinguishing the mathematical from the dialectical parts of the Divided Line in characteristically illuminating and forceful terms (23): “Plato uses the Divided Line to announce at peak volume that anyone who admires mathematics as queen of the sciences is as deeply mistaken as someone who ranks the whole of sense perception, and beliefs based on it, as cognitively superior to the whole of intellection.” Although their mathematical training is useful for creating an ethos of truth-loving in the future rulers of Callipolis (188-90), Broadie usefully distinguishes the methods of mathematics from what the rulers will need to do and how dialectic arising from the G-question will allow them to get it done. Emphasizing the role of hypotheses in the Line’s dianoetic section, Broadie offers a compelling argument that dialectic’s purpose is not to ground mathematics on examined and ultimately satisfactory hypotheses; the objects of the two methods are as different as the three kinds of angle are from the virtues. Although less successful on the mathematic section’s dependence on images of sensible things—after all, her conception of an interrogative Good applied to concrete empirical situations necessarily brings dialectic “down-to-earth”—her account of its dependence on hypotheses is magisterial.

Nothing has so far been said about the twelve densely-packed pages of the book’s first part: “Approaching the Sun-Good Analogy” (1-12) and above all, these are the pages that all students of Plato’s Republic must read and that will cause this review to end by initiating a critical dialogue with Broadie’s claims, the truest way to honor the dialectical nature of this deliberately provocative book. Pathbreaking is her emphasis from the start on the gulf between the Shorter and the Longer Ways (Section 1.2). Thanks to the latter’s infinitely greater theoretical yet also more practical illumination—and in a revealing revision of Oxford’s dominus illuminatio mea, ‘illumination’ becomes the philosopher’s dominus meus in the book’s epigraph—it is only on the Longer Way that the sun-like Good can add essence or οὐσία, thanks to the G-question, to the Shorter Way’s merely inchoate account of virtues. While her sharp distinction between Short and Longer Ways is welcome in theory (see especially 5-6), Broadie’s approach diminishes this distinction’s value in practice. As already indicated, her argument depends throughout on imagining in remarkably literal and realistic terms what the rulers of Callipolis would actually do down in the Cave. Ever since Aristotle, extreme realism has been applied to the workings of the City as described along the Shorter Way in Republic 4 but never has so realistic and down-to-earth an approach been applied to the City’s ideal rulers as described on the Longer. A resolute determination to confine Plato’s account of the properly Platonic function of the sun-like Good to the imaginary rulers of a non-existent City (4 n. 9) underlines the point that it is not Broadie’s relentlessly practical account of what Plato means by dialectic in his Republic but rather her own ongoing dialectical practice in offering and defending that account that makes her last book invaluable.


[1] “The Good of Others in Plato’s Republic.” Proceedings of the Aristotelian Society 73 (1972-1973), 19-36, on 21.