Averroes's Commentary on Plato's “Republic” goes far beyond merely commenting on the original. With the benefit of 1,500 years of hindsight, it reckons with important works of philosophy that would have been completely unknown to Plato. Averroes mentions three authors of such works by name: Galen, whom he mostly rebukes, Aristotle, and Alfarabi. It would be hasty to assert that by including such extraneous material, Averroes departs from Plato, but, at the very least, he updates him on account of historical developments.

The importance of Averroes's post-Platonic additions is evident from the very structure of the work. The part of it that can plausibly claim to be a commentary on Plato does not begin until 27.24, almost seven pages into Rosenthal's Hebrew text. Averroes begins to address the subject of war, corresponding to Republic 374b, having skipped all of book 1 and the majority of book 2, with only two brief references to them in the opening section (CR 22.27–30, 23.31–33, cf. 47.29–30and 105.25–27). Averroes does not justify his omission until the very end of the work, when he states that the opening part of the Republic does not contain any of the demonstrative arguments of which his commentary is comprised (CR 105.25–27, cf. 21.4). He is more immediately forthright about the reasons for what he includes in its place. In keeping with the demonstrative focus of the work, Averroes replaces Platonic dialectic with a substantial discussion of science. Having divided practical science into two parts, one about general habits and actions and another about their implementation, Averroes explains: “Before we begin a point-by-point explanation of what is in these arguments [of Plato], we ought to mention the things pertinent to this [second] part [of practical science] and explained in the first part, that serve as foundation for what we wish to say here at the beginning” (CR 22.6–8). Averroes's introduction concerns above all the first part of political science, while the Republic proper contains only the second. Averroes attributes to Plato only a small part of the ensuing discussion, concerning justice, the division of labor, and the arrangement of the soul (CR 22.22–24.6, esp. 22.27, 23.31). The other passages are inspired by Aristotle and especially Alfarabi. Averroes appears to substitute scientific arguments from Aristotle and Alfarabi—mainly about science, philosophy, courage, and war—for Plato's dialectical introduction about justice and the founding of the just city.

Plato's Republic occupies a central place in the study of political philosophy. From antiquity down to the present day, it has remained one of the most frequently read, taught, and interpreted books in the philosophical canon. It is therefore both perplexing and unfortunate that the greatest medieval commentary on the work remains so little studied. Averroes's Commentary on Plato's “Republic” provides a worthy subject for the present anthology, which, as far as we know, represents the first scholarly collection of its kind.

Averroes was by no means the first of the Muslims falāsifa to study the Republic. Inspired by Alfarabi's claim that Platonic philosophy was the true philosophy, generations of medieval Islamic falāsifa strove to understand and expound the Republic. But Averroes alone has bequeathed a full-blown commentary on Plato's most famous work. Even Alfarabi, who made such frequent and profitable use of Plato, has left us a commentary only on Plato's Laws. So while Averroes's Commentary on Plato's “Republic” clearly shows the influence of his predecessors, most notably Alfarabi and Ibn Bajja, it takes the project of commenting on Plato a step further. At the same time, Averroes's inimitable creation is far from being a simple commentary. It is divided into three treatises, the first corresponding roughly to books 1–5 of the Republic, the second to 6–7, and the third to 8–10. But in no case does Averroes simply replicate Plato's argument, without some additions, subtractions, or changes of his own. Most dramatically, Averroes omits many of the most memorable passages of the Republic, such as the opening discussion of justice, the divided line, and the Myth of Er. He also adds a wide variety of arguments for which one looks in vain in Plato, including a digression of some fifteen pages in the center of the work and an original account of the nonvirtuous regimes. Some of these insertions may be traced to Aristotle and Alfarabi, but others appear to be Averroes's own.

Averroes's Uncertain Knowledge of Plato

Averroes's deviations from the original text of the Republic, combined with the puzzling absence of any medieval Arabic translations of the dialogue or any unimpeachable testimony to their existence, has understandably led some scholars to doubt his access to the dialogue, at least in the form that it has come down to us.

The original Hebrew was published in Iyyun: The Jerusalem Philosophical Quarterly 8 (April 1957): 65–84. A complete English translation follows.

No commentary on the Politics can be counted among Averroes's commentaries on Aristotle's works. The Arab philosopher recognized, at a certain point, this deficiency. He thought at first that Aristotle's political teaching was contained at the end of the Nicomachean Ethics, until the existence of this other book become known to him. But here is this problem: the Politics never reached the western regions of Islam. Was it never translated into Arabic in the Middle Ages? There is some evidence for this assumption, although the question still remains open.

Having no other option, Averroes composed a commentary or, more correctly, a summary with some additional remarks on Plato's Republic. It appears, as Rosenthal has shown, that Averroes was influenced in his efforts by an abridged paraphrase of that book, a work of Galen that has not come down to us. But he also pursued his commentary in the tradition of Alfarabi, on whom the political books of Plato had a decisive influence. In the text under discussion. Averroes draws from the writings of Alfarabi, and even quotes them on occasion.

The Arabic original of Averroes's Commentary on Plato's “Republic” has not been preserved. A Hebrew translation of it has, however, come down to us, from the pen of Samuel ben Judah of Marseilles, who reviewed his translation and revised it twice between the years 1320 and 1322. So has a Latin translation made in 1539 on the basis of the Hebrew translation. This last translation, the work of Jacob Mantino, a Jewish doctor from Tortosa, was printed in Venice among the writings of Aristotle in 1550. It is, however, a rather free translation that should be trusted only to a very limited degree. Rosenthal has therefore performed a great service in bringing before an audience of those interested in medieval thought one of the most important texts belonging to the field of political philosophy. The agreeable result includes, in addition to the Hebrew text, a translation of that text into English, an introduction, and notes, several of which are of fundamental significance.

The Hebrew manuscripts are full of challenges, and it is E. Rosenthal's great achievement to have managed, through many years of diligent work, to overcome most of the difficulties lurking in this text.

The most famous, or infamous, proposal in Plato's Republic concerns the rule of philosopher-kings. Throughout the long history of the philosophical reception of Plato, this theme has been explored, restated, and rejected in countless ways. One of the most original treatments of it comes from the Andalusian philosopher Averroes, in his Commentary on Plato's “Republic.” The title of this inventive work must not be construed too narrowly. On every major theme in the Republic, Averroes deviates, either by omission, addition, or editorial commentary, from Plato. His treatment of the philosopher-kings will make use of all these techniques. Before turning to this topic, I wish to make some general remarks about the work as a whole.

Averroes announces his departure from Plato in the first sentence of the work, with the somewhat cryptic promise to remove all dialectical arguments from the Republic while preserving the demonstrative arguments (CR 21.4). Dialectic is associated, etymologically and semantically, with dialogue. Sure enough, Averroes expunges not only the dialogue form of the original but also its principal characters. This choice should not simply be attributed to ignorance: even if we were to assume that Averroes had only a summary of the original, he would surely have known of the existence of the characters Socrates and Thrasymachus through Alfarabi. In fact, Averroes himself mentions Thrasymachus and his arguments about justice in his Middle Commentary on the Topics.

The form with which Averroes replaces the dialogue can hardly be described as a straightforward treatise. Averroes attributes the arguments he presents to a variety of sources, as indicated by expressions such as “we said,” and “Plato said.” In addition, Alfarabi and Aristotle are often cited, paraphrased, or even plagiarized, in what is ostensibly a commentary on Plato. This implies a dialogue of sorts between not only Averroes and Plato, but Aristotle and Alfarabi as well. One is tempted to say that the discussions between Socrates, an aged father, a sophist, and several young Greeks is replaced by a discussion between four great political philosophers across the ages, orchestrated by the latest representative of this august group. On this point, it is useful to recall Leo Strauss's observation, that no Platonic dialogue relates a discussion among equals. If dialectic involves a superior person such as Socrates leading less accomplished interlocutors by the hand, then Averroes's new, demonstrative form consists of a dialogue between equals to whom historical accident never granted the opportunity for a face-to-face meeting.