Biographical sources

Proclus’ biography was drafted less than a year after his death by his student and immediate successor, Marinus. It is not just a story of his life, but an account of the Neoplatonic family of meanings “concerning well-being” (περὶ εὐδαιμονίας) also translated “concerning true happiness.” Marinus paints a portrait of a philosopher-saint, who fulfilled all the virtues possible for a mortal. His exposition makes liberal use of rhetorical forms and material,¹ while he treats rhetoricians as if he were in Socrates’ time. He adopts silence on the violent events of the fifth century ad; except for a handful of dark hints, one could think that Proclus lived in some period of classical antiquity.

The other main source for Proclus’ life and character is a collection of fragments from Damascius, who was head of the philosophy School from ad 515 until its forced closure in 529/31 in the reign of Emperor Justinian. He wrote a Life of his teacher Isidorus, himself a student of Proclus. It amounts to a Philosophical History.² Damascius’ account is also based on the Neoplatonic theory of virtue but is sensitive to the degree that thinkers fell short of his version of the philosophical ideal. It is full of biting anecdotes about the fifth-century professors. He admires Proclus but receives him more critically. Damascius does mention the personalities and events that punctuated the fifth century’s historic changes, from the murdered philosopher Hypatia (ad 415) to Attila the Hun, to Anthemius, the last noteworthy emperor in Rome (467–72), who had attended Proclus’ classes, and to the rule of Italy by the Goths (493).

Proclus’ life in facts and figures

Proclus (Πρόκλος) was “the head of the philosophy School in Athens”³ from about the age of twenty-five until his death on April 17, 485. We do not know for sure when he was born: according to the reported lifespan, in 410/11; or, according to a horoscope, on February 7 or 8, 412.

The first biographical fact we have about Proclus is that he lived “a long life of five and seventy years in all (ὅλοις)” (Marinus, Vita Procli 3.55–56). The age of seventy-five is repeated in a later chapter (VP 26.27–36). But these references to Proclus’ lifespan disagree with the date calculated from a horoscope (more on this later).

His parents possessed “significant wealth” (VP 4.29), probably inherited,⁴ certainly earned by his father, who was “greatly famous in the royal city in the exercise of litigation (δικανική)” (VP 8.23–24). M. Edwards suggested that Proclus’ father, Patricius, was a Roman aristocrat appointed as a procurator or fiscal magistrate in the imperial capital.⁵ His mother was “Marcella, the legitimate wife of Patricius” (VP 6.2–4). Siblings are not mentioned. His birth date/year is not given.

Proclus was born in “Byzantium” (VP 6.6): the classical Greek name of “Constantinople.” At the time of Proclus’ birth it was the capital of the Eastern Roman Empire; in his lifetime it became the sole capital of the Roman world, following the end of the empire in Rome in ad 476, during the reign of Emperor Zeno in Constantinople. His parents, however, came from Lycia (southwest Asia Minor). “Soon after he was born,” they returned to the city of Xanthus, Lycia, which “became his own homeland” (πατρίδα αὐτοῦ γενομένην) (VP 6.15–18). Later records refer to him as Proclus “from Lycia” (Simplicius, In Physica 601.15, etc.), or “Lycian” (Proclus’ own Epitaph; Suda P2473).

He was taught by a grammarian in Lycia, but at an unspecified point during his adolescence he travelled to Alexandria in the province of Egypt, to be “able to choose for himself his teachers” (VP 8.4–5). One such teacher was a sophist called Leonas, who invited him to live with his family and introduced him to “those who held the reins of Egypt.” A grammarian, Orion, of a priestly cast, instructed Proclus in religious practice. Proclus also attended classes in rhetoric and Latin; he was being prepared to follow in his father’s profession (VP 8.22–23). Leonas was asked by the “governor of Alexandria,” Theodorus, to visit the capital, and Leonas invited the “eager” Proclus to accompany him (VP 9.1–7).

On this visit to his birthplace, Byzantium, something dramatic happened that prompted Proclus to break with his life so far. We are given no human reason, Marinus briefly saying that “the goddess” exhorted him to turn to philosophy and attend the schools in Athens (τὰς Ἀθήνησι διατριβάς) (VP 9.11). Probably, he was inspired by the imperial establishment of a Byzantine higher School in 425, which included a chair in philosophy.⁶ It was a period fraught with Athenian “Hellenic” aspirations.⁷

When Proclus returned to Alexandria, he stopped the rhetoric lessons (VP 9.12–15) and studied Aristotle’s logical treatises (VP 9.33) with a philosopher Olympiodorus. He studied mathematics with a namesake of Heron, who inducted him into “piety” (θεοσέβεια), a coded reference to the late antique pagan “Hellenism.” Proclus made this big change to his life while still a “stripling boy,” an adolescent (μειράκιον) (VP 9.20). We do not know if his parents approved of it, for they have disappeared from the biography.

Proclus next set off for Athens itself (VP 10.5–10). In three chapters Marinus tells us how he was adopted by the Athenian philosophers through a series of events steeped in Neoplatonic meaning. Setting this aside, Proclus profited from a well-connected supporter, whom Marinus almost dismisses. Nicolaus was a Lycian “fellow-citizen,” who studied rhetoric (like Proclus) and later became a famous career sophist. From other sources we know that he was brother to a patrician grammarian in Byzantium, and that in Athens he was a student both of Lachares, the scholarch of rhetoric, and of Plutarch, the scholarch of the philosophy School.⁸ Lachares had philosophical interests and kept company with the philosopher Syrianus (VP 11), who seems to have been deputy leader of the School.⁹ Although Proclus was still an adolescent (μειράκιον), after attending a philosophical seminar he impressed both Lachares and Syrianus (VP 11.15–23) by his manner of “free expression” (παρρησία), a term indicative of a philosopher, but originally of Athenian free speech.

At this juncture Marinus gives us an age: he was “a youth (νέος) not yet in his twentieth year” (VP 12.2) when Syrianus introduced Proclus to the head of the philosophy School, Plutarch (Nestorius’ descendant biologically or as a student). The latter had been responsible for introducing Iamblichean Neoplatonism in Athens. Although Plutarch was “extremely old,” he took Proclus in to study Aristotle’s De anima, and Plato’s Phaedo, both of these works dealing with the soul. Plutarch’s daughter Asclepigeneia (the older) initiated him into the theurgical way (ἀγωγή), “handed down to her by her father from the great Nestorius” (VP 28.12–15). Proclus lodged with Plutarch, who “called him frequently his child” (τέκνον) (VP 12.17), while Proclus called Plutarch his “forefather/grandfather” (προπάτωρ).¹⁰

After approximately two years (VP 12.28) Plutarch died and “entrusted this youth” and his grandson Archiadas to his successor Syrianus, who invited Proclus “into his house and his philosophic life.” Although Proclus later retained his parental property in Xanthus (VP 14.18–20), this became his new family: Syrianus his “father” (πατήρ) and the Platonic “succession” (διαδοχή) his life (VP 10.15–16; 12.31–36; 29.31–35).

“In less than two full (ὅλοις) years” (VP 13.1) Proclus studied with Syrianus “all the treatises of Aristotle, logical, ethical, political, physical, and the theological knowledge that transcends these (i.e. the Metaphysics)” (VP 13.2–4). When these “lesser mysteries” were sufficiently learned, Syrianus instructed him in the “mystagogy of Plato,” so that his education might proceed in “orderly sequence” (see later, on the Neoplatonic system of education). The textbooks on politics had been Aristotle’s political treatises, Plato’s Laws and the Republic (VP 14.1–3). He worked “night and day,” so that he “delivered so much in a short time that when he was still in his twenty-eighth year he wrote many and various commentaries…filled with knowledge, especially the one on the Timaeus” (VP 13.10–17). He reached the “contemplative” grade.

By then Proclus had succeeded Syrianus as head of School, but we are left to infer the circumstances. According to Damascius and Marinus (VP 26), after Syrianus had completed the studies on Plato, he asked Proclus and a “colleague,”¹¹ “Domninus, a Syrian philosopher who was also a successor” (VP 26.8), to choose between lectures on the Orphic or the Chaldaean theology. The two disagreed, while Syrianus “did not live very long.” At some stage Proclus wrote a “cathartic treatise” against Domninus’ “superficial understanding of philosophy” that “distorted” Plato (Damascius, Historia philosophica 89).¹²

Marinus does not tell us when Proclus became head of School. It is estimated that he spent six years under philosophical instruction: about three years on Aristotle and three years on Plato.¹³ So, he became the leading “Platonic Successor” around the age of twenty-five or twenty-six.

Marinus does offer fascinating glimpses into Proclus’ political influence in Athens and cities abroad (VP chs. 14–16), his cosmopolitan practices (VP 19), his intrepid worship of polytheistic deities under a Christianized regime (VP chs. 29–33), his daily schedule (VP chs. 22 and 24), and the running and location of the School (VP chs. 22–23, 29). The Neoplatonic School flourished at the foot of the Acropolis. Plato’s Academy had been located outside the ancient city walls, which Proclus visited to honor the memory of the ancestors’ souls (VP 36.16–17).

Damascius draws attention to an unexpected fact: Proclus’ School was truly wealthy. By contrast, the Alexandrian philosophy School relied on student fees and city grants, and its leader was preoccupied with finances. In Damascius’ eyes (Hist. phil. 118), Ammonius (former student of Proclus’, and son of Proclus’ colleague Hermeias) was “a man of sordid greed for gain, who saw everything in money-making terms.” Still, the Alexandrian School continued well into the sixth century, after the closure of the Athenian.

Assuming it is not a rhetorical device, 1,000 Roman “solidi” of gold annually had the following purchasing power:¹⁴ 1–2 solidi for a year’s food subsistence; 4–5 solidi for annual rations for a soldier (the word derived from “solidus”) or 30 for full provision; 35-solidi salary for a grammarian or rhetorician, around 100 solidi combining public and private income; 50–90-solidi salary for a doctor-in-chief, or a judge; 188 solidi (1,500 in eight years), exceptionally lucrative teaching funded from public and private sources (Libanius, Orat. 1.61); 600-solidi salary for a crown-counsel, fiscal advocate (like Proclus’ father?); 700–800 solidi for a province governor; 1,000-solidi pension to chief palace minister.

Proclus exercised pastoral care to those under his charge, and to the city, according to the traditional and Neoplatonic views of involvement with the world. In his fortieth year, it is said, he stopped a drought and an earthquake, and he spoke inspired utterances again in his forty-second year, when he attained the virtue of “theurgy” (θεουργία) (VP 28).

He led an ascetic life, refrained from eating meat except token meat for religious purposes, and abstained from carnal sex. Damascius records that Proclus was one of four Neoplatonist virgins in a century: Hypatia (Hist. phil. 43a), Proclus (56), Marinus (97b), Sarapion (111). Only “some divinity prevented Proclus” from marrying “the most beautiful and noble woman of Alexandria,” Aedesia, a philosopher relation of Syrianus (Hist. phil. 56). Above all, Proclus stayed active, avoiding “sloth.” His daily routine was:

During his tenure he tried to lead the philosophical “undisturbed” life (ἀταραξία) (VP 20.10–11). But his hot temper was a fact that even Marinus “could not deny” (VP 16.10–20). Moreover, Marinus admits that “external events fell on him unexpectedly and those that seemed to be contrary to reason” (VP 20.18–20; VP 15.15–17), while Proclus speaks of “the many unending troubles” (Hypotyposis astronomicarum positionum 1.17–18).

Proclus left Athens for a year and went to Lydia, north of Lycia (VP 15.33–35). His return may be dated after Emperor Theodosius’ death in 450, or earlier in the 440s.¹⁵ There he made a philosopher friend, to whom, after his return, he addressed the book Outline of Astronomical Hypotheses,¹⁶ and who could be the Pericles of Lydia (VP 29.17) cited in the Commentary on Plato’s Parmenides and the Platonic Theology. Later Proclus witnessed the removal of Athena’s statue from the Parthenon (VP 30.5–11) by the Christians, the event perhaps being dated to ad 465.¹⁷

Damascius, on the other hand, gives a wealth of worldly reports about the fifth-century ad events, with references to Attila, the emperors Valentinian (Rome) and Theodosius II (Constantinople) (Damascius, Hist. phil. 50–51, 115); to Proclus’ statesmen students, such as the “Hellenic-minded” Byzantine patrician Anthemius (Hist. phil. 51, 77a), who became emperor of the West (but was killed by his Germanic general); to his fellow-student, the philosopher Severus, who was visited in Alexandria by Indian Brahmans and became Anthemius’ chief minister in Rome (Hist. phil. 51c–d); to the rise of the Ostrogoth leader Theodoric, “who now has supreme rule over the whole of Italy” (Hist. phil. 51). In Byzantium Plutarch’s student Hierocles (420s/30) had been beaten until he was bathed in blood (Hist. phil. 45b). During a rebellion (484–488/9) in the reign of Emperor Zeno, “Hellenic” associates were persecuted. In Alexandria philosophers suffered (Hist. phil. 119), and two prominent theurgists Horapollo and Heraiscus were tortured (Hist. phil. 117a–c), while Damascius and his teacher Isidorus escaped to join Asclepiodotus of Alexandria, a dear student of Proclus’, who flourished in the city of Aphrodisias, in Caria near Lycia.

In his last five years Proclus’ health deteriorated, his exceptional adherence to “his harsh and insupportable diet…and other acts of endurance (διακαρτερήσεις) having exhausted the natural well-being of his body” (Marinus, VP 26.37–41). He thought back to his student days, when the dead Plutarch had appeared to him in a dream and prophesied that the number of Proclus’ note-pages on the Oracles would count his years: seventy. Later, his reliable powers of recollection were failing him selectively (VP 20.11–15).

The philosophy School seems to have been a challenging place (ἀνταγωνίζομαι: Damascius, Hist. phil. 54), where Proclus channelled his hot-tempered, competitive ambition for honor (φιλοτιμία) into the pursuit of excellence.¹⁸ Although Marinus was taking on the responsibilities of successor, he was infirm, and Proclus “feared that the true golden chain of Plato might abandon our city of Athena” (Damascius, Hist. phil. 98e–f, 97, 151–152). The School’s future leadership was being contested by Asclepiodotus, but especially by Hegias and his father, Theagenes, who had compelling connections (Damascius, Hist. phil. 99a, 100a, 101, 145a–b). Theagenes was a wealthy archon (chief magistrate) of Athens, “our benefactor,” and married to Asclepigeneia (the younger), daughter of Archiadas the grandson of the scholarch Plutarch. The philosophy succession went for a while to Isidorus, who was present as a pallbearer at Proclus’ funeral.

Proclus was buried in a joint grave with Syrianus on the Athenian hill Lycabettus (VP 36.24–30). Marinus does inform us of when Proclus died (VP 36.1–4, 37.1–12). He triangulates the date from different sources: by reckoning the number of years (124) since the accession of the Hellenists’ hero, Emperor Julian (around ad 361); by naming the contemporary Athenian archons; by citing the date and month in Athenian and Latin calendars: April 17. Best of all, Marinus locates the year of Proclus’ death between two objective celestial phenomena: eclipses of the sun, one already witnessed (January 14, 484, shortly after sunrise), and one predicted to be observed in Athens. If the latter corresponded to the annular solar eclipse of November 1, 487, Proclus may have died in 486. Although this option would help to resolve the problem of his year of birth, its possibility has been ranked as minor. The most likely candidate is the partial eclipse of May 19, 486.¹⁹ So, we arrive at the date of Proclus’ death: April 17, 485.

Symbolism of Proclus’ life and ages

Marinus highlights the biographical data for what mattered to the Neoplatonist circle of philosophers. They are presented not simply as literal facts to be verified by exact science, but as meaningful stages in the “procession” of an inspired philosophical soul.

Proclus’ birth marked the “descent” of his soul into the mortal “shell.” Porphyry estimated Plotinus’ time of birth by “reckoning backwards” his lifespan from his time of death, for Plotinus “never told anyone the month in which he was born nor the day of his birth” (Porphyry, Vita Plotini 2.35–44). Marinus does not seem to have known Proclus’ birthday either, but he similarly furnishes us with the lifespan and time of death. The birthdays they celebrated were the traditional ones of Plato and Socrates as representatives of divine life (Marinus, VP 23.15–17, and Porphyry, VPlot. 2.40–44).

Before Proclus joined the Athenian School around his twentieth year, he was a “stripling boy” (μειράκιον). In Greek pedagogy and in Plato’s Republic the term “μειράκιον” signified the age range in which one was fit to sustain rigorous training at preparative stage. The twentieth year corresponded to the age grade of a senior trainee, who can learn comprehensively.²⁰

The subsequent ages of (twenty-one implied), twenty-eight, forty-two, seventy, fall into a pattern of seven: a highly meaningful number in the (Neo)Pythagoreanism known to Proclus and applied to a scheme of the significant ages of man. Moreover, by meaningful coincidence, the twenty-eighth and fortieth years match ages of important events in Plotinus’ life.²¹ On Proclus’ own evidence (In Parm. 683.18–27), the Greeks traditionally considered a man older than seventy no longer an elder (πρεσβύτερος) but a geriatric case.²² The seventieth year seems to have marked the symbolic end of one’s intellectual life.

Death signified the release of one’s soul from the body, and “return” towards true reality. Marinus celebrates Proclus’ death soberly, by recording the eclipses that marked “the departure of the light in philosophy” (VP 37.11–12). The reported age when he died, seventy-five, corresponded to the age limit for holding the top office of Examiner in Plato’s Laws (946c). Seventy-five was also the “icon” of the non-rational psyche living in the realm of generation, as discussed at length in Proclus’ Commentary on Plato’s Republic 2.19–70 (cf. Plato, Timaeus 35b–36e). Reaching seventy-five may have symbolized the limit of one’s physical capabilities.

The matter of Proclus’ horoscope

Towards the end of the biography Marinus concludes the case for Proclus’ life by bringing retrospective proof from the “disposition of the stars under which he was born” (VP 35); the text contains a set of astronomical data for astrology, of unknown provenance. Marinus had a special interest in mathematics (e.g. Damascius, Hist. phil. 97g, Test. III 81; Photius 181), and his surviving works include astronomy and methods of calculation.²³ The Athenian School’s activities in philosophy, astronomy, and its “interpretive” arm, astrology, were the specific targets for the ban as enforced locally on Emperor Justinian’s authority (Watts [Reference Watts2006], 128–142).

The horoscope’s data have been amended and recalculated with greater precision in relation to the date for which it was cast,²⁴ but questions remain. Regarding the birth year, are Proclus’ lifespan and horoscope two irreducibly different pieces of information?²⁵ Can they be made to fit by shortening the seventy-five years, so that 485–412 = 73 years? For example, by counting the seventy-five as lunar years, equivalent to seventy-three solar ones (Boissonade citing Fabricius)?²⁶ Or by making it an aggregate of Proclus’ being in his seventieth year (sixty-nine years) plus in the fifth year (four years) thus 69 + 4 = 73 years?²⁷

Why was the horoscope cast not for the latitude zone of Byzantium, Proclus’ actual birthplace, but for the latitude zone of Rhodes?²⁸ Rhodes is located close to Xanthus (Lycia), Proclus’ parental place, which “became his own native land,” “soon after” his birth. Was it procured in Proclus’ youth (A. Jones [Reference Jones1999])?

Horoscopes were calculated from astronomical tables spanning long periods of time, and they were often produced many years after the person’s birth.²⁹ Horoscopes of dead natives offered a comparison of the chart’s predictions with the person’s actual life, but with a hindsight that benefited from over-abundant possible explanations.³⁰ Was the horoscope “set out” (ἐξεθέμην; VP 35.1–5) after Proclus’ death to corroborate the fulfillment of his destiny as presented in his biography or to complete the hagiography (Siorvanes [Reference Siorvanes1996])? Interpretation is a horoscope’s raison d’être. There were artificial and fictional horoscopes, whose astronomical positions were made up to be astrologically consistent.³¹

Since Galileo’s time, the Proclus horoscope studies have concentrated on the astronomical data but have not researched what mattered more: the meaning. Relevant sources that can be consulted include: Firmicus Maternus, who knew of Plotinus; Porphyry’s astrological work; Paulus of Alexandria (fourth century), and the commentary on Paulus probably derived from lecture notes of the sixth-century Alexandrian Neoplatonist, Olympiodorus. Proclean material can be sought in his major commentaries On Plato’s Republic and On Plato’s Timaeus.

Here are some questions to investigate. Does the horoscope correlate with what we know about Proclus from biographies (e.g. his temper, love of work)? What life changes, character profile, profession, and suchlike, emerge from the horoscope’s amended data compared with the raw data? What are the meanings for Proclus’ “lot” (κλῆρος; VP 35.3) of Fortune, and “lot” of Daimon? What would be the readings for Proclus’ length of life, according to his “lot,” “ascendant,” “starter of life,” and “destroyer” signifiers? The “length-of-life” astrological calculation was most complex and dangerous: it was punished as high treason if attempted on emperors.

Neoplatonic education and Proclus’ biography

For Proclus, philosophical education was a form of induction of the soul by degrees (e.g. VP 22.1–15), based on Plato’s scheme of graded knowledge (Republic books 6–7). It was intended to stimulate the soul to think of her innate truths, to learn in the manner proposed by the Platonic theory of recollection. Doing philosophy was not just a cerebral affair. Since Plato, it was “the gymnastics of the soul” (Rep. 498b). Since the Hellenistic schools it was an ἀγωγή (see on Proclus’ work: περὶ ἀγωγῆς), a training-up in virtue, a course of living.

The training required natural ability, experience in abstract thinking, and desire for learning.³² In the stage of “the lesser mysteries” the students were taught Aristotle on logic and language, developed their ethical and political grounding, and were exposed to Aristotle’s physical topics. With the mathematics of arithmetic, geometry, music (harmonics), and astronomy they crossed the “bridge” from the sense-perceived to the intelligible domain, indicated by Aristotle’s “theology,” the Metaphysics. On the Plato course, the students read a carefully chosen selection of the Platonic dialogues (typically twelve) entering “the greater mysteries” or “mystagogy.” They studied both the logical anatomy and theological significance of the principles of being. Reading Homer was an allegorical way of understanding the soul’s journey in the material world (e.g. the Odyssey), and of encountering revealed knowledge of the gods.³³

Marinus wrote Proclus’ Life, not as a biographical history (VP ch. 2), but as an exemplar of the Neoplatonic conception of the soul’s journey, through training in ascending degrees of virtue, to true happiness (εὐδαιμονία). One starts with (VP 3.1–7) the basic qualities that nature (φύσις) and one’s parents endow, that early training inculcates, and that the soul possesses (VP ch. 3, chs. 4–5). Then, one cultivates ethics (VP chs. 7–13) as exemplified by the political, social virtues (VP chs. 14–17). Next comes the “cathartic” virtue, which cleanses the soul from bodily considerations and restores it (VP chs. 18–21), ready for the rigors of intellectual contemplation: the “theoretical” virtue (VP chs. 22–25). This culminates in the contemplation of unity, which substantiates intelligible being but transcends it. “Beholding” (θεωρία) leads to revealed knowledge. Orphic and “Chaldaean” literature aid the soul towards theurgy (VP chs. 26–33).³⁴

Proclus’ works and the curriculum

As his biography tells us, Proclus could write 700 lines a day. About a third of his writings survive (roughly eighteen of fifty-four titles), numbering at least 1,093,884 words³⁵ (without counting the fragments surviving elsewhere and pieces in non-Greek). In volume it surpasses the Aristotle corpus (1,015,272 words), and in total Proclus would have competed with the superlative Galen corpus of 2,608,974 words. The works’ word-counts are owed to the database of the Thesaurus Linguae Graecae, University of California at Irvine.

Our sources consist of manuscripts that survive in Greek, in Arabic, and in Latin. Our knowledge of Proclus’ works has benefited enormously from the devotion of Professors L. G. Westerink, H.-D. Saffrey, A. Segonds, and C. Steel. For the works that have not survived, references can be found in Proclus, in Marinus, in treatises of his colleagues (e.g. Hermeias), his students (e.g. Ammonius), their students (e.g. Asclepius, Damascius, John Philoponus, Olympiodorus, Simplicius), and others. Byzantine collections such as Photius’ Library (ninth century), the encyclopedic Suda lexicon (tenth century), and Arabic sourcebooks such as Ibn al-Nadim’s Kitab al-Fihrist (tenth century) offer intriguing references to the reception of Proclus and to otherwise unknown pieces of his work.

We can divide his works according to form, audience, or subject, or according to date of composition (up to Proclus’ early thirties [Commentary on Plato’s Timaeus and “much else”], middle [on Fate, Existence of Evils], and late in his life [Commentary on Plato’s Parmenides, the Platonic Theology]). Although he did distinguish different types of interpretation, such as ethical, physical, logical, and theological, his monographs, essays, and commentaries address much the same areas of study. To him, even the hymns are philosophical, addressing the principle(s) whither one’s soul aims to “return.”³⁶

Here, his works are listed by their connection to topics of Proclus’ curriculum (his polemic against Domninus has not survived: “πραγματεία καθαρτικὴ ἡ ἐπιγραφὴ τῶν δογμάτων τοῦ Πλάτωνος”; ref. Suda D1355). In this way I can present in context Proclus’ missing works and offer relevant alternatives and/or further references. Their provenance has been verified afresh with the primary sources.

Proclus taught and wrote on Aristotle, Plato, Euclid, Ptolemy, Homer, and others. The curriculum started with a general but very methodical introduction to the aims, definitions, and sources of philosophy. This course covered the different schools of Greek philosophy (including Hedonism), and the different ways by which philosophical material can be examined. In the Aristotle-dominated syllabus, “five are the degrees of philosophy: logic, ethics, physics, mathematics, theology” (Elias, In Categorias Aristotelis 121.5–8, and Olympiodorus, Prolegomena 9.31–10.25). For the Plato syllabus, the academic Neoplatonists were well aware that Plato’s dialogues could be arranged chronologically. However, as philosophers, they selected those whose central theme fitted their “scope” of study (Anonymous, Prolegomena in Platonis philosophiam 24–26, 21–23).

Note on marginal symbols used: bullet point indicates an extant or reported Proclus work; “-” no known work by Proclus; “>” see (also) under another curricular topic; “?” unresolved or other attribution.

Introductory level

1. Proclus, Joint and Comparative Reading (συνανάγνωσις) of philosophy, including Introduction to Aristotle in Ten Chapters (ref. Elias, In Cat. 107.3–26 and ff.). This “Proclean treatise” (σύνταγμα Πρόκλειον) is not extant. Can be reconstructed from Ammonius, Olympiodorus, John Philoponus, Simplicius, “David and Elias” on Prolegomena and on the Categories.³⁷

2. Porphyry, Introduction (Isagoge) (Εἰσαγωγή) to Aristotelian logic. Proclus, Commentary (ref. Asclepius, In Metaph. 142.36–37): not extant.

   Compare commentary by “Ammonius.”

3. Proclus, Outline (ὑποτύπωσις) of the Platonic Philosophy (ref. John Lydus, De Mensibus, 2.8.59, 4.7.25–26. Cf. Proclus, In Alc. 10.3–11.17): elements extant in lecture notes produced in sixth-century Alexandria, the Prolegomena to Platonic Philosophy.³⁸

The “lesser mysteries”

Logic, inclusive of language³⁹

1. > Aristotle, Categories. See under Introductory level: Proclus, Introduction to Aristotle (ref. Elias, In Cat. 107.24–26), and Proclus, Commentary on Porphyry’s Isagoge.

   Compare commentaries by “Ammonius,” Olympiodorus, John Philoponus, Simplicius, David/Elias.

2. • Aristotle, On Interpretation. Proclus, Commentary (ref. Ammonius, In De interpr. 1.6–11; 181.30–32; Stephanus, In De interpr. 46.25–47.12): not extant.

   Compare commentary by Ammonius, and Proclus, Commentary on Plato’s Cratylus.⁴⁰

3. • Aristotle, Prior Analytics. Proclus, Commentary (ref. Commentaria in Aristotelem Graeca [CAG] 4.6 “Ammonius,” In Anal. pr. 43.30–31; 31.24; 39.2):⁴¹ not extant.

   Compare commentaries by “Ammonius,” John Philoponus.

4. • Aristotle, Posterior Analytics. Proclus, Commentary (ref. Philoponus, In Anal. post. 111.31–112.36):⁴² not extant.

   Compare commentary by John Philoponus (and pseudo-Philoponus).

Ethics: general (including Aristotle, Stoics, Pythagorean Exhortations)

1. - Studied. No commentary by Proclus on Aristotelian or Stoic ethics.

   Compare Simplicius, Commentary on Epictetus’ Handbook.

2. • Proclus, Commentary on the Pythagorean Golden Verses (in Latin, Carmina aurea) (ref. Arabic Fihrist, of Syriac translation); perhaps from an earlier source: partly extant in Arabic translation.

3. > Proclus, Commentary on Hesiod’s “Works and Days.” The work’s “scope” suggests it aimed to educate and calm the passions.⁴³ See also below under Revealed religion and literature.

4. • Proclus, Commentary on Plotinus’ Enneads (ref. Damascius, In Parm. 4.14.5–8 (Combès); “David/Elias,” In Isagoge, CAG 18.2, xxi; preamble attached to Iamblichus, Myst. 1.1–10; scholion at Proclus, In Remp. 2.371.18; Catalogus Astrologorum Graecorum, vol. v.1, 189.28–190.5): short fragments extant, mostly on Ennead 1, incl. 1.8 on the origin of evils.⁴⁴

   On matters affecting ethical choice:⁴⁵

5. • Proclus, Ten Doubts concerning Providence (13,405 words), Latin translation, a Greek version by the Byzantine Isaac Komnenos.

6. • Proclus, On Providence, Fate and What Depends on Us, A Reply to Theodorus, the Mechanist (5,479 words),⁴⁶ Latin translation, also Greek version.

7. • Proclus, On the Existence of Evils (9,437 words), Latin translation, also Greek version.

Ethics: Politics

1. - Studied Aristotle’s political treatises, Plato’s Republic and Laws (ref. Marinus, VP chs. 13–14). No commentary on Aristotle’s Politics or Nicomachean Ethics (called “political science,” Eth. Nic. 1.2).

   Compare Proclus, Investigation of the Objections of Aristotle, in the Second Book of the Politics, to Plato’s Republic, essay in Proclus, Commentary on Plato’s Republic (2.360ff.) under Plato Dialogues, Ethical: Political.

2. • Proclus, On the Way of Life (περὶ ἀγωγῆς) (ref. Suda P2473); possibly on political ἀγωγή to mystical union (cf. Proclus, In Remp. 1.81.3ff.; 1.84.25–26; 2.66.11–19; In Tim. 3.351.19–29). Two books: not extant.⁴⁷

Aristotelian physical topics (including On the Soul)

1. • Proclus, Elements of Physics (7,688 words). With a set of initial terms and fifty-two propositions, it presents a demonstrative account, drawing on Aristotle’s Physics and On the Heavens, with a Neoplatonic aim. Some topics appear in the Arabic Fihrist as separate titles, On the Indivisible, Definition of the Origins of Natural Phenomena.

2. • Aristotle, Physics, On the Heavens, etc.: studied. Relevant Proclus fragments, including from Investigation of the Objections of Aristotle to Plato’s Timaeus (see below) and On the Nature of Place (περὶ τῆς τοῦ τόπου φύσεως) (ref. Proclus, In Remp. 2.199.22, and scholion at 2.380.30), appear in commentaries on Aristotle by Simplicius, John Philoponus, Olympiodorus.

3. • Proclus, Letter to Aristocles. Fragment of a discussion on place and on materiality of the heavens (ref. Simplicius, In Phys. 9.615.15): not extant. On Proclus’ physics, see also under Plato: Second Cycle, Physics: Timaeus.

4. - Aristotle, On the Soul (De anima): studied, no known commentary by Proclus.

   Compare commentaries by John Philoponus and pseudo-Simplicius. For references to De anima, see also in commentaries on Plato’s Phaedo.

Mathematics, inclusive of astronomy

1. - Introduction to the Arithmetic of Nicomachus. Proclus “believed he had the soul of Nicomachus” (ref. Marinus, VP 28.34–36). Perhaps lectures passed on to Ammonius.

   Compare commentaries by Asclepius of Tralles, John Philoponus.

2. • Proclus, Commentary on Euclid’s Elements, book 1 (84,453 words). Influential treatise on the status of mathematics, read by Copernicus and in Galileo’s circle, quoted by Kepler. Treatise includes many important theorems, e.g. on Parallel Lines, which may be listed indiscriminately as separate titles.

3. - Aristoxenus, Harmonic Elements, book 1 (see Proclus, In Tim. 2.169.17–26, 2.183.13–22): no commentary by Proclus.

   Compare Porphyry, Commentary on Ptolemy’s Harmonics.

4. • Proclus, Outline (ὑποτύπωσις) of the Astronomical Hypotheses (24,977 words). Critical assessment of the authoritative astronomer Ptolemy.

5. > See Proclus, Compilation (συναγωγὴ) of the Mathematical Concepts of the Timaeus, under Plato: Second Cycle: Timaeus.

   Attributed to Proclus:

6. > “Proclus Ouranodromos” (ref. Catalogus Astrologorum Graecorum vol. vi, p. 82, ed. Kroll, 1903): two fragments of this claimed work. Not a treatise title: derived from the epithet “οὐρανοδρόμε Πρόκλε,” which occurs in Byzantine scholia on Hesiod’s Works and Days (one fragment is extracted from a scholion) accompanying the introduction of Proclus, Commentary on Hesiod (see under Literary works).⁴⁸

7. ? Paraphrase of Ptolemy’s Tetrabiblos, Anonymous Commentary on Ptolemy’s Tetrabiblos; Sphaera (text from first-century bc astronomer Geminus).

8. ? On Eclipses: sixteenth-century Latin translations “ex Proclo.” Perhaps sourced from chapters on Eclipses from the Tetrabiblos and/or Astrologia Dialogus, e.g. chs. 10–12.

Aristotle’s Metaphysics

1. - Studied. No work by Proclus. Compare commentary by Syrianus.⁴⁹

The “greater mysteries” in two cycles

First cycle of Plato’s Dialogues: from knowledge of self to that of the Good

Preparatory

1. Alcibiades I. Proclus, Commentary (68,762 words): survived to Alc. page 116b, source for the rest in commentary by Olympiodorus.

Ethical: Political

1. Gorgias. Proclus, Commentary (ref. Proclus, In Remp. 2.139.18–20, obliquely In Remp. 2.140.23–25 and 2.178.3–6), Syriac translation (ref. Arabic Fihrist): none extant.

   Compare commentary by Olympiodorus.

2. Republic. Proclus, Commentary on Plato’s Republic (167,711 words).⁵⁰ A joint and comparative reading (συνανάγνωσις) of diverse essays, including on definition of justice, value of Homeric myths in philosophy, Aristotle’s objections.

Purificatory (cathartic)

1. Phaedo. Proclus, Commentary (ref. Marinus, VP 12; Proclus, In Remp. 2.179.12–15, 2.183.23–25, obliquely, In Remp. 2.178.3–6; affirmatively, Elias, In Isag. 2.10–11); Arabic translation by Ibn Zur’a (ref. Arabic Fihrist): none extant.

   Compare commentaries by Damascius, Olympiodorus.

   On cleansing and restoring the soul from bodily considerations, see:

2. Proclus, On Plato’s Three Proofs of Immortality (ref. Priscianus, Solutionum ad Chosroem ch. 1, pp. 47–49; Arabic Fihrist): arguments preserved in Arabic and Latin.

Theoretical: Logical

1. Cratylus. Proclus, Commentary (28,788 words): survived (to 407cd) in notes from a student.⁵¹

2. Theaetetus. Proclus, Commentary (ref. Marinus, VP 38.14–15, “he liked it greatly”; Proclus, In Tim. 1.255.25–26): not extant.⁵²

Theoretical: Physical

1. • Sophist. Proclus, Commentary (ref. Proclus, In Parm. 774.26): not extant, but elements of it in Proclus, Commentary on Plato’s Parmenides.⁵³

   Compare commentary by the chief Renaissance Neoplatonist, Ficino.⁵⁴

2. - Statesman (Politicus). No separate commentary, but see Proclus’ interpretation in the Platonic Theology, book 5, chs. 6–8.⁵⁵

   Compare the Renaissance Ficino, who continued the Neoplatonic linking of the Sophist with the Statesman.

Theoretical: Theological

1. Phaedrus. Proclus, Commentary (ref. “On the Palinode,” Proclus, In Parm. 949.39, 1088.27; In Remp. 2.282.12–17, 2.312.3, 2.339.15–16; “On the Palinode of Phaedrus,” Proclus, In Remp. 2.309.20–23), cf. Theol. Plat. book 4:⁵⁶ not extant.

   Compare commentary by Proclus’ colleague, Hermeias.

2. Symposium. Proclus, Discourse of Diotima (ref. scholion at Proclus, In Remp. 2.371.14): not extant.

   Compare commentary by the Renaissance Neoplatonist, Ficino.

Completion of first cycle

1. Philebus. Proclus, Commentary (ref. Damascius, Hist. Phil. 38a): not extant. Read Proclus, Platonic Theology, book 3, chs. 8–14. Compare commentary by Damascius.

   On the Good, see also:

2. Proclus, On the Three Monads. “As we said in the book (βιβλίον) on these three monads” (ref. Proclus, In Remp. 1.295.24–25); the three monads of the Good are beauty, truth, symmetry (Proclus, In Remp. 1.295.18–28; cf. Proclus, In Tim. 2.267.20, Plat. Theol. 3, ch. 18; Damascius, In Phileb. 2.3–4, 237.1–244.6ff.): not extant.

3. Proclus, The First Good (ref. Arabic Fihrist). If it is not an Arabic version of the Elements of Theology (see under Neoplatonic “theology”), it may be Proclus’ untitled “monobiblon” (ref. Damascius, De principiis 1.86.16–17): none extant.⁵⁷

Second cycle of Plato’s Dialogues: knowledge of the cosmos and the divine

“Summit” of Physics

1. Timaeus. Proclus, Commentary : extant in Greek (325,501 words) to Tim. page 44cd (total pages 92c); extant Arabic translation of Proclus, Commentary on Tim. 89e–90c.

2. Proclus, Investigation of the Objections (ἀντιρρήσεις, ἀντειρημένα) of Aristotle to Plato’s Timaeus (ref. Proclus, In Tim. 2.278.27–29, 279.2; John Philoponus, De aet. mundi 31.11, 82.14, 138.21, 167.4, etc. to 626.3; Simplicius, In Cael. 7.38.4); possibly a preliminary to the Commentary: not extant.

3. Proclus, Compilation (συναγωγή) of the Mathematical Concepts of the Timaeus (ref. Proclus, In Tim. 2.76.24); possibly an appendix to the Commentary: not extant.

   On Proclus’ views of the cosmos, see also:

4. Proclus, On the Eternity of the World. On Plato’s Timaeus, arguing that the cosmos must be eternal like its creator, not finite in time (interpretation of certain first- to second-century ad Platonists). Known as “Eighteen Arguments against the Christians”…“Proclus is the second after Porphyry to move his defiling and insulting tongue against the Christians” (ref. Byzantine Suda P2473) (text also translated in Arabic): extant as part of John Philoponus, On the Eternity of the World against Proclus.

5. Proclus, On Light (περὶ φωτὸς) (ref. John Philoponus, De aet. mundi 18.19–19.16, noted by Saffrey and Westerink [Reference Saffrey and Westerink1968], lviii): not extant.

“Summit” of Theology

1. Parmenides. Proclus, Commentary (177,636 words) and conclusion of the “first hypothesis” extant in Latin.

   On Neoplatonic “theology” as “first philosophy”:

2. Proclus, Elements of Theology (28,278 words): Proclus’ most read book, demonstrating the Neoplatonic metaphysics in 211 propositions.⁵⁸

3. Proclus, Platonic Theology (149,543 words): the fruit of the Parmenides interpretation.⁵⁹ Platonic Theology is Proclus’ crowning opus.

Revealed religion and literature

1. • Proclus, Commentary on Chaldaean Philosophy (1502 words): a sample is extant.

2. • Proclus, On the Hieratic Art (1048 words), on theurgy: a small part extant, and perhaps from:

3. • A larger work on Mythical Symbols⁶⁰ (ref. Proclus, In Remp. 2.109.1–2; cf. In Remp. 2.65.3 “in the hieratic art”): not extant.

4. • Proclus, On the Mother of the Gods (ref. Marinus, VP 33):⁶¹ not extant.

5. • Notes on Syrianus, Theology of Orpheus (ref. Marinus, VP 27), and a work labeled Agreement of Orpheus, Pythagoras, Plato (ref. Byzantine Suda, ascribed both to Proclus and Syrianus): not extant.

6. • Proclus, On the Gods in Homer (ref. Byzantine Suda, ascribed both to Proclus and Syrianus): not extant.

7. • Proclus, Commentary on the Whole of Homer (ref. Byzantine Suda P2473): not extant.

   Compare essays on Homer in Proclus, Commentary on Plato’s Republic. For specimen Neoplatonic allegorical reading, Porphyry, The Cave of the Nymphs in the Odyssey.

8. • Proclus, Commentary on Hesiod’s “Works and Days” (ref. Byzantine Suda P2473): an introduction and assorted scholia extant.

9. ? Scholarship assigns these works to a namesake “Proclus” (ref. Byzantine source Photius’ Library 239.318–322): Chrestomathy Grammatica, an outline on reading Homer (also ref. in Suda, under Proclus); On the Epistolary Style, on letter writing.

10. • Proclus, Hymns 1–7 (to Athena, Aphrodite, et al.) (1151 words).

11. • Proclus, Epigrams (three, of which two are theurgical verses, VP 28) and his own Epitaph (VP 36).

Philosophical exegesis

Much of Proclus’ surviving work consists of commentaries on Plato. We have partial commentaries on the First Alcibiades, the Timaeus and the Parmenides, as well as a summary of some of his commentary on the Cratylus and a collection of essays on the Republic. The lengthy commentary on the Timaeus deals with less than half of the dialogue, down to 44d, while the commentary on the Parmenides deals with the text only down to 142a, again less than halfway through the dialogue. Likewise the material we have from the commentary on the Cratylus goes only to 407c, covering twenty-four out of the fifty-seven Stephanus pages of Plato’s text, and the commentary on the First Alcibiades breaks off in the middle of a discussion of 116a–b, having commented on thirteen out of thirty-two Stephanus pages. It seems reasonable to assume that in all these cases Proclus did in fact discuss the whole dialogue, but that his commentaries have not survived in full.⁷ The First Alcibiades, often treated as spurious in modern times,⁸ was accepted as genuine by the Neoplatonists and was the first dialogue read in the standard curriculum of the pagan Neoplatonic schools.⁹ The Timaeus and the Parmenides formed the culmination of that curriculum and according to Proclus’ biographer, Marinus, the Timaeus was the dialogue which Proclus regarded as the most important.¹⁰ These three commentaries are clearly related to Proclus’ teaching activity in the Platonic school at Athens. The Cratylus too was one of the dialogues read in the standard Neoplatonic curriculum. The commentary we have consists of excerpts, made by a later author from a full commentary.¹¹ We are thus somewhat further removed from Proclus’ lecture room when we read this text than when we read the commentaries on the First Alcibiades, the Parmenides, or the Timaeus but, like them, this commentary too reflects the activity described by Marinus in the following passage:

It is worth noting here that Marinus specifically describes Proclus’ main teaching activity as exegesis, using the Greek verb ἐξηγεῖτο. The commentaries of the sixth-century Alexandrian Neoplatonist Olympiodorus, which, like those of Proclus, derive from teaching, are divided into individual lectures, each of which is further subdivided into general interpretation (θεωρία) and study of individual words or phrases (λέξις). Proclus’ commentaries similarly distinguish between general discussion (τὰ πράγματα) and study of particular details (ῥήματα / καθ’ ἕκαστα) but the division is less mechanical and the text is not divided into lectures. It has been suggested that this difference between Proclus and Olympiodorus reflects the difference between the two thinkers, or the different nature of their audiences.¹² It might also indicate that Proclus’ commentaries, while originating in the classroom, were worked over and revised before the written version was finalized in a way that those of Olympiodorus were not.

The work known as Proclus’ commentary on the Republic is in fact a collection of sixteen essays plus an additional discussion of Aristotle’s objections to Plato in Politics 2. Strangely, the Republic did not form part of the standard curriculum in the Neoplatonic schools of late antiquity¹³ but the essays we have may still be related to Proclus’ activity as a teacher. Essays 1–5, 7, 8, 10–12, 14, and 15 all belong together. Some have suggested they formed a course of introductory lectures on the Republic, perhaps for a general audience of “serious amateurs.”¹⁴ Yet it has also been argued that essays 1, 3, 4, and 5 presuppose philosophical knowledge and expertise and that essay 1 in particular is addressed to an audience of exegetes, or future exegetes.¹⁵ Whatever the intended audience for these essays, it is worth noting that the heading for the first essay uses the term συνανάγνωσις, “reading in class,” and that in the opening lines of the essay Proclus addresses his audience as “you.”¹⁶ Essay 6 derives from a special lecture given at the annual celebration of Plato’s birthday.¹⁷ Essay 16 is a commentary on the Myth of Er in Republic 10.¹⁸

Proclus also wrote commentaries on other Platonic dialogues which have not survived. He himself refers to commentaries on the Theaetetus, on the myths in the Gorgias and the Phaedo, and on Socrates’ “palinode” in the Phaedrus.¹⁹ Later authors mention commentaries on the Phaedo, on the whole of the Phaedrus, on the Philebus, and on Diotima’s speech in the Symposium.²⁰ These were all dialogues read as part of the Neoplatonic curriculum mentioned above. Interestingly, some of Proclus’ own references to exegesis of these dialogues are more easily interpreted as references to oral teaching than to published commentaries. The phrase at In Parm. 1128.29 “as we showed in expounding the Phaedrus” (ὡς ἐδείκνυμεν ἐξηγούμενοι τὸν Φαῖδρον) could well be an allusion to oral teaching while the words at In Tim. III.295.3–4 “we have also shown this in our discussions about the Phaedrus” (καὶ τοῦτο δέδεικται μὲν ἡμῖν ἐν ταῖς εἰς Φαῖδρον συνουσίαις) must be an allusion to a lecture or a seminar rather than to a written commentary.²¹ Similarly the commentary on the Phaedrus written by Proclus’ fellow-student Hermias appears to be based on the lectures by Syrianus which Hermias and Proclus both attended and includes some comments and questions posed by Proclus.²²

The systematic Platonic Theology offers exegesis of Plato of a rather different kind. In this work, in six books, Proclus offers a discursive account of his metaphysical system and attempts to show that all aspects of it can be found in the works of Plato. He sets out the plan for the work in Theol. Plat. I.2.9.8–19: first the general notions about the gods, “as transmitted by Plato”; next the ranks, characteristics, and procession of the gods “defining them in Plato’s manner and referring everything to the assumptions of the theologoi,”²³ and finally the hypercosmic and encosmic gods “celebrated here and there in Plato’s works.” This is indeed the plan which he follows although the text we have comes to an end with the account of the hypercosmic gods in book VI. The account of the general notions about the gods in book I classifies the attributes of the gods in groups of three according to the Platonic dialogue which, according to Proclus, deals with each group, referring back to the Laws in chapters 14–16, the Republic in chapters 18–21, the Phaedrus in chapters 22–24, and the Phaedo in chapters 26 and 27. In the same way the lengthy account of the gods as they appear at the different levels of Proclus’ system, starting with the One in book II and working down the system to the hypercosmic gods in book VI, constantly relates these gods, who are also metaphysical entities, to specific passages of Plato. Exegesis of the hypotheses of the Parmenides plays a crucial role in structuring Proclus’ theological and metaphysical system but other Platonic texts such as the myth in the Phaedrus are also important sources for his exposition.²⁴

In Theol. Plat. I.4 Proclus distinguishes between four modes of theological exposition practiced by Plato, inspired, dialectical, symbolic, and iconic (i.e. using images, εἰκόνες). He links the inspired mode of exposition with the Phaedrus, the dialectical with the Sophist and the Parmenides, the symbolic with the mythical parts of the Gorgias, Symposium, and Protagoras, and the iconic with the Timaeus and the Statesman. He goes on to describe the symbolic mode as Orphic, the iconic as Pythagorean, the inspired as appropriate to theurgy, and the dialectical as peculiar to the work of Plato. In its context this passage offers both a programmatic statement about how Proclus will interpret particular dialogues within the Platonic Theology and a way of harmonizing differences between dialogues by appealing to the different modes of exposition. At the same time this theory of modes of exposition offers a way of harmonizing Plato with other texts and with the rites of theurgy. The theory also appears in the commentary on the Parmenides, at 645.7–647.18, in a preliminary discussion of the literary style (χαρακτήρ) of that dialogue. Elsewhere Proclus does not consistently distinguish between symbolic, iconic, and inspired modes of discourse but he is consistent in taking the approach to Plato which lies behind that distinction, seeking to smooth over difficulties within the text, rather like a modern interpreter appealing to the principle of charity, and seeking also to demonstrate agreement between Plato and what he regards as the other sources of truth.²⁵

In commenting on Plato, Proclus draws extensively on earlier exegesis by a wide range of authors. For example, in the commentary on the Timaeus he reports the views of the second-century Platonists Atticus and Numenius and the third-century literary critic Cassius Longinus as well as those of Plotinus, Porphyry, Iamblichus, Theodorus of Asine, and others. Pride of place is always given to the views of Syrianus, with whom Proclus rarely disagrees. This feature of Proclus’ commentaries has meant that, like the Alexandrian Neoplatonist commentaries on Aristotle, they have often been treated primarily as a source for the views of earlier philosophers. However, again like the Aristotelian commentators, Proclus is not simply recording earlier views. He engages actively with the tradition of commentary on the texts under discussion, adjudicating between rival interpretations and drawing on a very wide range of material from the Greek cultural tradition. He not only considers large issues of philosophical interpretation but also addresses detailed points concerning particular words. Sometimes he comments on matters such as Plato’s style or his skill in characterization, using the vocabulary and approach of the literary critical tradition.²⁶ He interprets both the Atlantis story at the beginning of the Timaeus and the myth of Er at the end of the Republic as allegories, treating them in the same way as he treats Homer or the Orphic poems.²⁷

Many of these features of Proclus’ exegesis of Plato can be seen in the discussion of the spherical shape of the universe, at In Tim. II.68.6–79.14. He starts by quoting the relevant lemma from the Timaeus, 33b1–8, and then proceeds to offer three Platonic “proofs” of the spherical shape of the cosmos. The first proof develops the point made by Plato at Timaeus 33b2–4, that the appropriate shape for the living cosmos which includes all living things within itself is the spherical one which includes all other shapes. The second proof expands on the idea that the spherical shape is particularly appropriate or fitting (πρέπον), appealing not only to a passage in Plato’s Laws (898a–b) but also to Parmenides’ comparison of reality to a sphere in fr. 8.43–44 and to Empedocles, interpreting the latter along Neoplatonic lines.²⁸ The third proof picks up Plato’s use of the word συγγενής, “akin,” in Timaeus 33b2 and argues that spherical shape is akin to the cosmos, to the demiurge, and to the paradigm which provides the demiurge with the model for the physical world. Proclus supports his argument by referring to two lines from Orphic poetry, to the remarks about shape in Parmenides 137d–e, and to Iliad 18.401, a line which describes the jewelry made by Hephaestus, understood by both Proclus and Syrianus as referring allegorically to enmattered forms, fashioned by Hephaestus as demiurge of the sensible world.²⁹ He uses an allusion to the Chaldaean Oracles to contrast the activity of Hephaestus with that of the demiurge in the Timaeus.

Having expounded his three proofs, Proclus turns to discuss a problem raised by the text: why did Plato say it is necessary that the cosmos should have a spherical shape? His answer leads him initially into discussion of issues about the relationship between the sphere and other shapes, with reference to what follows in the Timaeus about the formation of bodies from the five regular solids. The problem under discussion was evidently traditional and Proclus goes on to spend a couple of pages reporting Iamblichus’ arguments on the matter (72.6–73.26) before turning to a summary of material found in Aristotle, De caelo 2.4 in the course of which he makes fleeting reference to Plato’s Statesman 270a (73.26–75.18). He then turns to mathematical arguments for the spherical shape of the cosmos, referring to “the views of experts in this field” (75.18–76.29). The material here finds parallels in the work of the mathematical writers Geminus, Cleomedes, and Theon of Smyrna as well as in Ptolemy. Towards the end of this section of his commentary Proclus refers to Plato’s own discussion of polyhedra in Timaeus 53c–56b and to mathematicians who use the demonstrations of Euclid and Archimedes respectively.

Up to this point Proclus has been concentrating on the first part of the lemma, 33b1–4. The last part of his commentary on it, 76.29–79.14, picks up some particular details from 33b5–8, with another reference to Laws 898b, quotation of a line of Pindar which Plato himself quotes at Theaetetus 173e6, reference back to an earlier passage of the Timaeus (30b1–3), quotation of a phrase from Laws 757b, quotation of a sentence from the work attributed to Timaeus of Locri which Proclus took to be a genuine source independent of Plato’s Timaeus, and reference back to his own account of the arguments in Aristotle’s De caelo.³⁰

Both in his commentaries on Plato and in the Platonic Theology Proclus treats Plato’s work as a unified corpus. He regularly addresses the difficulties which arise in reconciling apparently conflicting passages either within or between dialogues. So, for example, In Parm. 648.1–658.22 deals in part with a problem which is familiar to modern interpreters of Plato, namely the differences between the views of dialectic in Republic 7, the Phaedrus, and the Sophist. Proclus is concerned not only to argue that Plato’s conception of dialectic is the same in all three dialogues but also to reconcile an apparent contradiction between Republic 7.534e, 537e–539d and Sophist 253e on the one hand and Parmenides 135e on the other. Because he is commenting on the Parmenides he starts not with the question of how to reconcile the method of collection and division which appears in the Sophist and the Phaedrus with the remarks about dialectic in Republic 7 but with the conflict between Parmenides’ encouragement of the young Socrates to engage in dialectical exercises like those of Zeno and the view expressed by Socrates in Republic 7 that dialectic is not a suitable activity for those who are young and lacking in experience.

Characteristically, Proclus argues that there are three different kinds of dialectical activity suitable for different interlocutors. One kind is an exercise for training the young, used by Socrates in the Theaetetus and the Lysis; another is the contemplation of the intelligible world and the Platonic Forms – according to Proclus here this second kind of dialectical activity is what Plato has in mind not only in Republic 7 but also in the Phaedrus and the Sophist – while the third kind is what Socrates uses to expose the pretensions of the sophists in dialogues such as the Gorgias and the Protagoras and in arguing with Thrasymachus in Republic 1. We might suppose that Parmenides’ remarks to the young Socrates at the beginning of the Parmenides would imply that any dialectic in that dialogue is an activity of the first kind, but that would conflict with Proclus’ view of the dialogue’s overall theme and significance.³¹ He therefore claims that the Socrates of the Parmenides is a special case, capable of the second kind of dialectical activity despite his youth. He pulls in the account of hypothetical method in the Phaedo and argues that this too belongs under the second kind. Because Proclus pays close attention to the wording of Plato’s text, the use of the word ἀδολεσχία (“babbling”) at Parmenides 135d5 gives him particular problems. His method of dealing with it is again characteristic: he points out, quite correctly, that Parmenides says this term is used by “the many” and also considers other passages in Plato where the word is used.

In this example Proclus interprets the views of dialectic found in different Platonic dialogues in such a way as to present Plato’s views as a unified body of doctrine, allowing for differing dialectical practices by claiming (not unreasonably) that Plato recognizes more than one kind of dialectical activity while insisting that the different uses of dialectic can be fitted into an interpretive framework of just three specific kinds. He moves easily from one dialogue to another, showing a close knowledge of a wide range of Platonic texts. It was that command of Platonic texts, both on the large scale and in detail, which made it possible for Proclus to compose the Platonic Theology in addition to commenting on particular dialogues.³²

Students in the Neoplatonic schools of late antiquity began by studying Aristotle, before going on to Plato. Marinus reports that Proclus himself followed such a course of study³³ and we do have some evidence for Proclus’ exegesis of Aristotle. The commentary on Aristotle’s De interpretatione by Proclus’ pupil Ammonius has connections with Proclus’ own commentary on Plato’s Cratylus and may reflect Proclus’ teaching of the De interpretatione.³⁴ A scatter of references in the Alexandrian Neoplatonist commentaries on Aristotle provides evidence for Proclus’ views on some of the issues which arise in expounding the Organon. Mention is also made of a work of Proclus which was a general introduction to the study of Aristotle, probably covering a standard set of preliminary general points.³⁵ Proclus’ only surviving work on Aristotle is the Elements of Physics, a selective summary of books VI and VIII of Aristotle’s Physics and book I of the De caelo. The occasion and purpose of this work are unclear; Proclus might have composed it for his students, to assist them in grasping Aristotle’s ideas about the physical world before they moved on to Plato.³⁶ There is also some rather sparse evidence for Proclus commenting on Plotinus, insufficient for us to determine the context and nature of his exegesis of the Enneads.³⁷

Exegesis of Euclid and Ptolemy

Proclus’ surviving works include a commentary on the first book of Euclid’s Elements and a short work on astronomy, the Hypotyposis, much of which presents the hypotheses of Ptolemy’s Almagest.³⁸ The commentary on Euclid, like Proclus’ commentaries on Plato, derives from teaching. In Eucl. 200.11–18, 210.17–28, 272.12–14, and 375.9 all allude to an audience of beginning students although much of the material in the commentary seems suitable for a more advanced audience. Perhaps the more advanced material was introduced when Proclus wrote up his lectures on Euclid to produce a full commentary.³⁹ His interest in Euclid is primarily philosophical and the prologues to the commentary include some important discussions of the nature of mathematical objects and of the role of imagination (φαντασία) in enabling us to visualize such objects.⁴⁰ He draws extensively but critically on earlier commentaries, referring both to mathematicians such as Hero and Pappus and to a wide range of philosophers including Aristotle, Speusippus, Eudemus, Porphyry, Theodorus of Asine, Plutarch of Athens, and, of course, Syrianus.⁴¹ Proclus comments in detail on the definitions, postulates, axioms, and propositions set out in the first book of the Elements, applying similar methods of exegesis to those he uses in expounding Plato. So, for example, in commenting on definition I,1 and definition I,3 he deals with conflicting interpretations of the order of generation and priority of the mathematical concepts of point, line, surface, and solid by arguing that the “arithmetical” or Pythagorean interpretation applies in the immaterial world while the “geometrical” or Platonic one applies in the world of material things. At the same time his commentary on definition I,1 also mentions a different solution to the problem of these conflicting interpretations which is developed further in commenting on definition I,6. He now suggests that Euclid’s definitions are “images” (εἰκόνες) which should be understood allegorically. This approach makes it possible to apply the “geometrical,” Platonic approach to both the material and the immaterial, understanding the former as an image of the latter.⁴²

Proclus’ attitude to Ptolemy is rather different from his view of Plato, Aristotle, or Euclid. He seeks to maintain the view of astronomy presented by Plato in Republic 7.530 and is thus committed both to saying that true astronomy is concerned with the divine and to denying astronomical phenomena such as the precession of the equinoxes, which had been discovered between Plato’s time and his own. The main purpose of the Hypotyposis is therefore to argue against Ptolemy but in order to do so Proclus has to provide a summary of Ptolemy’s views.⁴³

Exegesis of Homer

Proclus’ exegesis of Homer can be found primarily in the sixth essay of his commentary on the Republic. Here he responds to Plato’s criticisms of Homer in Republic 2, 3, and 10 in a number of different ways, including offering detailed exegesis of the passages of Homer which Plato singles out for criticism in Republic 2 and 3.⁴⁴ There was a long tradition of defending many of these passages, which Proclus picks up and develops. So, for example, at In Remp. I.115.1–117.21 Proclus discusses the deceitful dream sent by Zeus to Agamemnon at the beginning of Iliad 2. Plato in Republic 2.383a7–8 regards this passage as problematic since it contradicts the principle he has just laid down, that the gods are without falsehood and do not deceive human beings. Proclus starts his discussion of the deceitful dream with the traditional response, found in the Homeric scholia attributed to Porphyry, that the fault lay not in Zeus but in Agamemnon, who misunderstood the word πασσυδίῃ (“with all the army”) used by the dream and attacked the Trojans without Achilles.⁴⁵ He then reports the view of Syrianus, that this response fails to take account of Zeus’s providence and his desire to punish the Greeks for their behavior to Achilles. Syrianus was apparently prepared to admit that Zeus does deceive Agamemnon, for his eventual good. Finally Proclus offers a further solution to the problem, putting together the traditional response and the rather different view of Syrianus. He argues that the falsehood arises in Agamemnon because of his nature, in accordance with divine will and for Agamemnon’s own good; the falsehood does not actually come from the gods.⁴⁶

Proclus’ main way of defending Homer against Plato is through allegorical interpretation. For example, in In Remp. I.87–95 he argues that the Theomachy described in Iliad 20, like other mythical theomachies, should be understood in terms of Neoplatonic metaphysics as representing the contrasting forces that bring about procession and reversion, division and reunification. He reconciles the account of the gods fighting one another in Iliad 20 with passages such as Odyssey 6.41–46 describing the peace and calm of the gods’ dwelling on Olympus by pointing out that at the highest level of metaphysics the divisions which appear at lower levels no longer exist. Here he is not only claiming that, rightly understood, Homeric poetry and Platonic philosophy are not in conflict but is also treating the Homeric poems in the same way as he treats the Platonic corpus, as a consistent body of material in which contradictions can be reconciled by appealing to different levels within his system. It is also worth noting that Proclus does not consider the Theomachy of Iliad 20 in isolation. He discusses it alongside the battle between Zeus and the Giants popular in Greek literature and art and the less well-known Orphic myth of the fight between the Titans and Dionysus.

Like the Theomachy, Hera’s deception of Zeus and their union on Mount Ida, vividly recounted in Iliad 14.153–351 and censured by Plato in Republic 3.390b–c, was much discussed by defenders of Homer before Proclus. In In Remp. I.132–140 Proclus draws on Syrianus to offer a detailed allegory of the episode in terms of Neoplatonic metaphysics. He deals with another scandalous Homeric union, the story of Ares and Aphrodite told in Odyssey 8.266–369, in the same way at In Remp. I.141–143. All these allegories are based on Proclus’ assumption that Homeric poetry is capable of revealing fundamental truths, the same truths which can be found in the philosophy of Plato. In order to grasp these truths we need to read both Homer and Plato in the right way. The aim of Proclus’ exegesis of Homer is to show us how to engage in such reading.

Just as Proclus resolves apparent contradictions in both Homer and Plato by claiming that different passages apply to different levels within his system, so he argues that the inconsistency between Plato’s severe criticisms of Homer as dangerously mimetic in Republic 10, the respect with which Theognis is cited at Laws 1.630a, and the apparent praise of inspired poetry in both Phaedrus 245a and the Ion is to be explained by postulating a hierarchy of three types of poetry: much of Homer is inspired poetry of the kind praised by Plato in the Phaedrus and, according to Proclus, in the Ion, while Laws 1.630a refers to a second kind of poetry, concerned with giving moral advice, and the criticisms of Republic 10 apply only to mimetic or imitative poetry, the third and lowest kind.⁴⁷

In accordance with this belief that much of Homer is inspired and should be interpreted allegorically, Proclus throughout his works cites lines and passages of Homer as revealing fundamental truths. We have already seen that the description of the jewellery made by Hephaestus, in Iliad 18.401, appears in the discussion of the spherical shape of the cosmos at In Tim. II.70.21–26.⁴⁸ Elsewhere, at In Tim. II.27.16–28.7, Proclus alludes to Hephaestus’ role in the story of Ares and Aphrodite in Odyssey 8 in a context where he is expounding what he takes to be the god’s role in binding together opposites in the physical world. In In Tim. I.142.14–144.18 Plato’s mention of Hephaestus at Timaeus 23e1 leads Proclus to give a lengthy account of the god’s place in his metaphysical and theological scheme. This account refers not only to Homer but also to the Orphic myth of the mirror of Dionysus, as well as using a term borrowed from the Chaldaean Oracles (ἐργοτεχνίτης – “craft-worker”).⁴⁹ Proclus is reading the Iliad and the Odyssey in the light of his version of Neoplatonism while at the same time treating Homeric lines and episodes as confirmation of the truth of his philosophy.

We can see Proclus combining allegorical interpretation of Homer and allegorical interpretation of Plato in a passage from the Parmenides commentary, In Parm. 1036.24–1038.30, discussing 137b–c, where Parmenides suggests that the youngest of his interlocutors should be the one to answer his questions. Proclus interprets Parmenides’ four interlocutors, Zeno, Socrates, Pythodorus, and Aristoteles, as beings at different levels in the metaphysical hierarchy; Aristoteles, the youngest, is at the lowest level, that of a soul which can be led up to higher levels and then carried down again into the material world. Proclus first draws a parallel with the different levels of initiation in mystic rites and then compares Parmenides’ desire for a brief rest while his questions are being answered with the unwearied and providential nature of the gods. He illustrates that unwearied and providential nature by referring to the beginning of Iliad 4 where the gods are served nectar by Hebe. He goes on to interpret Aristoteles’ readiness to identify himself as the youngest interlocutor as an instance of the way in which souls and lower-level gods particularize the generic intellection of higher divine beings and backs up this allegorical treatment of the character in Plato with an allegory of Iliad 24.74–77. There Hera asks for “one of the gods” to call Thetis to her, and the call is answered by Iris. Proclus sees this as parallel to Aristoteles’ responding to Parmenides and interprets both passages as allegories of relationships between entities at different levels.

Exegesis of Hesiod, the Chaldaean Oracles, and the Orphic poems

When Plato criticizes the poets in Republic 2, he starts, at 377d–378a, by objecting to the stories of Kronos’ castration of Ouranos and Zeus’s deposition of Kronos as told in Hesiod’s Theogony. Proclus does mention Hesiod as well as Homer at In Remp. I.72.2–3, at the beginning of the sixth essay. That essay goes on to concentrate on the defense of Homer, but there is every reason to think that Proclus would interpret the account of the gods and their activities given in Hesiod’s Theogony in the same allegorical way as he interprets the treatment of the gods in Homer. The Theogony receives little detailed exegesis by Proclus, perhaps because he was more interested in the Orphic account of theogony. However, he did devote time to commenting on the Works and Days, reworking the scholia of Plutarch of Chaeronea and adding material of his own. In part we may see Proclus’ concern with the Works and Days as reflecting his broad interest in all aspects of Greek culture, not just in philosophy. In his first scholion (1.1–18) he contrasts the Theogony, concerned, according to Proclus, with the principles of divine providence, with the Works and Days, which aims at the moral benefit of its readers and has an educational aim (σκοπός). The statement that readers “should begin with this work” (ἀπὸ τούτου προσήκει τοῦ συγγράμματος ἄρχεσθαι) suggests that Proclus’ exegesis of Hesiod too belongs to some kind of teaching context. The actual scholia tend to emphasize the moral meaning of the text, and also show some interest in arithmology. Scholia LXVIII–XCIII offer an interpretation of the myth of the five ages which differs from those found elsewhere in Proclus, in In Remp. II.75.12–78.11 and In Crat. CXXIX.⁵⁰ It looks as though Proclus regarded the Works and Days not as inspired poetry but as belonging to the second of the three kinds of poetry described at In Remp. I.177.7–199.28.⁵¹

The Suda attributes works on Orphic Theology and on the Agreement of Orpheus, Pythagoras, and Plato with the Chaldaean Oracles to both Syrianus and Proclus while Marinus reports that Proclus composed a commentary on the Chaldaean Oracles but left only notes on the Orphic poems (chs. 26–27). Whatever the relationship of Proclus’ writings on the Chaldaean Oracles and the Orphic poems to those of Syrianus, it is clear that Proclus both studied and taught all this material.⁵² He himself refers to his commentary on the Chaldaean Oracles at In Remp. I.40.21–22. The few surviving fragments confirm, unsurprisingly, that Proclus interpreted the Oracles in terms of his own psychology and metaphysics.⁵³ In his other exegetical works he alludes frequently to both the Chaldaean Oracles and the Orphic poems, interpreting them allegorically in such a way as to harmonize them with both Plato and Homer. We have already seen how Proclus uses two lines from Orphic poetry in his discussion of the spherical shape of the universe, at In Tim. II.68.6–79.14, considers the Orphic myth of the fight between the Titans and Dionysus alongside the theomachy of Iliad 20 in In Remp. I.87–95, and combines allusions to Homer, Orphic poetry, and the Chaldaean Oracles in his account of Hephaestus at In Tim. I.142.14–144.18.

In the Platonic Theology the Chaldaean Oracles play a particularly important role in book IV. Here Proclus gives an account of the intelligible and intellectual gods, presented primarily through exegesis of the myth in the Phaedrus and the second hypothesis of the Parmenides. A phrase from the Chaldaean Oracles, “they both think and are objects of thought” (νοοῦντα νοεῖται), is used in the very first paragraph of IV.1, at 6.11, as evidence of the existence of these gods while at the end of the chapter, at 10.17–18, Proclus is keen to point out that he is not reading them into Plato from elsewhere (οὐχ ἡμεῖς ταῦτα φέροντες ἀλλαχόθεν τῷ Πλάτωνι προσάγομεν). He devotes IV.9 to arguing that the Chaldaean Oracles accord with the Phaedrus myth and IV.39 to reconciling particular triads of gods mentioned in the Chaldaean Oracles with the Parmenides. In IV.10 Proclus argues that the “region above the heavens” (ὑπερουράνιος τόπος) of Phaedrus 247c corresponds to the three Nights in Orphic theology.

Theol. Plat. V deals with the intellectual gods and is structured around the Orphic version of the myth of Kronos. Although Proclus’ main concern is to find the intellectual gods in a range of Platonic texts, particularly the Timaeus and the Parmenides, he explicitly argues in V.10 that Plato’s references to Kronos agree with Orphic doctrine and in both V.3.16.24–17.7 and V.35 he fits the Couretes into his system by combining the way they are depicted in Orphic poetry with references in both Plato and the Chaldaean Oracles.⁵⁴

Exegesis of divine names and theurgic rites

Proclus applies his methods of exegesis not only to texts but also to the names of the gods and the rites of theurgy. In Crat. LXXI takes Plato’s own use of Homer in Cra. 391–392 as the starting-point for an extended discussion of the names of the gods. Proclus there distinguishes between divine names, used by the gods themselves, and man-made names. Of the latter, some are the products of divine inspiration while others are the product of human knowledge (ἐπιστήμη) or of sense perception and opinion. This distinction allows Proclus to interpret the different names of the gods in Homer, Orphic poetry, and the Chaldaean Oracles as applying at different levels. He takes the etymologies of Plato’s Cratylus completely seriously and discusses them at length, treating the dialogue as a source of wisdom about the gods.⁵⁵ A similar distinction between divine and man-made names can be found in In Remp. I.169.25–170.26⁵⁶ and in the discussion of the names of the cosmos in In Tim. I.272.7–274.32.

The Chaldaean Oracles provided Proclus and other post-Iamblichean Neoplatonists with a theoretical basis for the rites of theurgy. These rites themselves were understood by Proclus as having symbolic significance, as we can see from two passages in which he offers an interpretation of a theurgic rite, In Remp. I.152.7–153.3 and Theol. Plat. IV.9.30.17–31.5. In the first passage Proclus, following Syrianus, interprets the funeral rites performed by Achilles for Patroclus in Iliad 23 as representing the theurgic rite of “immortalization” (ἀπαθανατισμός) and at the same time expounds the symbolic significance of the theurgic rite, for example treating the cup from which Achilles pours his libation as the cup used by the theurgist which symbolizes the “source of souls,” that is, the mixing bowl of Timaeus 41d.⁵⁷ In the second passage another theurgic rite, the simulated burial of an initiate leaving only the head exposed, is interpreted in terms of the Phaedrus myth.⁵⁸

Several times in the Cratylus commentary Proclus compares divine names to statues of the gods (ἀγάλματα). At In Crat. LI.19.12–24, it becomes clear that what Proclus has in mind are the statues used for theurgic animation. When Proclus deals with the names of the gods he always has in mind the names used in particular texts. His approach to the rituals of theurgy is also that of an exegete, seeking connections between these rituals and his authoritative texts.⁵⁹

The comparison of divine names to statues of the gods reappears in the Platonic Theology, at I.29.124.12–125.2. Here Proclus draws an analogy between the activity of the demiurge in producing copies of the primary forms in matter and the activity of the human intellect in fashioning likenesses of all things, especially of the gods, representing the uncompounded by things in combination, the simple by the variegated and the unified through multiplicity. This way of talking recalls the terms in which Proclus, like Plotinus and others before him, describes how myths offer symbolic presentations of higher, divine truths, setting out what in reality is eternally unified as a narrative account following a temporal sequence.⁶⁰ In this particular passage Proclus goes on to say that this is the way in which human intellect forms names for divine beings and to compare that with the way in which theurgists summon the gods by means of the tokens or “symbols” (σύμβολα) placed in the statues they are animating. For Proclus the whole world is like a vast theurgic statue. If we follow the analogy through, philosophy itself becomes a form of exegesis: when a Neoplatonic philosopher expounds the structure of reality he is engaged in the same kind of activity as when he explains the meaning of divine names, theurgic rites, or authoritative texts.⁶¹

Conclusion

We can see from the surviving fragment of Proclus’ work On the Hieratic Art that theurgy was based on the traditional idea of cosmic sympathy. Proclus there explains how particular stones, plants, and animals have an inherent connection to the sun, for instance, and others to the moon. The heliotrope, the plant which naturally turns towards the sun, is a particularly clear example.⁶² If we took this text on its own as a full account of the theory underlying theurgy we might suppose that such a theory depended on the likeness of the (theurgic) symbol to that which it symbolizes and was therefore quite limited in its application. However, in many other passages, including the one from Theol. Plat. I.29 mentioned above, Proclus extends his theory of symbols much more widely and allows for the possibility that opposites can represent by opposites.⁶³ This extension of the theory of symbolism could also be justified by the Neoplatonic principle that “Everything is in everything, but in each according to its nature” (πάντα ἐν πᾶσιν, οἰκείως δὲ ἐν ἑκάστῳ).⁶⁴ It opens the way for flexible, multi-layered exegesis of the kind described in this chapter.

When he comments on the texts which he regarded as fundamentally in accord with one another – the dialogues of Plato, the Elements of Euclid, the poetry of Homer and Hesiod, the Chaldaean Oracles, and the Orphic poems – Proclus treats them all as expressions of the same philosophical truths, referring readily from one to another, sometimes presupposing the Neoplatonic interpretation of a passage, sometimes explaining that interpretation more fully, depending on the context. Exegesis is fundamental to his way of doing philosophy, not only because so much of his time was spent on teaching through expounding texts but also because he saw the whole world as a system of symbols; for him the philosophy he found in Plato was the key to understanding that system.

Proclus’ “Platonic” theology

In a manner comparable with that of the Christian doctrine already evolved by his own time, Proclus’ theology is based on the twin sources of revelation and reason.¹ For Proclus, the philosophical appropriation of revelation takes place in the first instance through the formal exegesis of Plato’s dialogues, among which the Parmenides and the Timaeus are considered to have almost universal importance, the Philebus and the Phaedrus also becoming crucial documents in certain contexts.² The philosophical appropriation of revelation also depends on the formal exegesis of certain writers on whom Plato himself is thought to have relied. Sometimes Proclus cites philosophers such as “Timaeus of Locri,” who is presumed to have specifically inspired Plato’s own dialogue Timaeus, as did earlier sources.³ However, he more often refers generically to “the theologians” (θεόλογοι), who can be identified by the content of their citations as the authors of the “Orphic”⁴ or the Homeric poetry.⁵ Given that the most profound insights can only be achieved by a philosopher who also practices theurgic ritual, the studies of Plato and these earlier philosophers and theologians must be supplemented and indeed guided by a careful study of the revelation that is the most important of all because it comes from the gods themselves: the Chaldaean Oracles.⁶ Finally, the synthesis of all these revelations is most often not claimed for himself but attributed by Proclus in a self-effacing manner to “my teacher” (ὁ ἡμέτερος καθηγεμών) Syrianus, the greatest of the earlier commentators on Plato, the oracles, and many other texts.⁷

Given the methodological dichotomy of revelation and reason, it is important to understand that even Plato’s writings fall primarily into the first category rather than the second in Proclus’ eyes.⁸ It is true that writings of Plato such as the Parmenides provide us with models of rational procedure that are worthy of imitation. In the extant portion of his commentary on that dialogue Proclus explains in some detail that the method of dialectic illustrated there is superior to the Aristotelian syllogistic and why it is so superior. However, the abundant testimonies regarding the no longer extant but more important section of the commentary make clear where the real importance of the Parmenides lies. It is most valuable because of the “intellectual intuitions” (νοεραὶ ἐπιβολαί)⁹ in which the various deductions regarding the One yield not just properties of real things but “symbols” (συνθήματα) of different orders of gods.¹⁰ Careful study of the wording of Proclus’ text shows us what is at issue here. Epibolai are the points at which the normally discursive reasoning of our partial soul transcends itself with momentary incursions into the non-discursive realm of intellect, while sunthēmata are the verbal or visual symbols which are employed in theurgic ritual and whose enigmatic meanings can be explored by meditative reflection. Thus, the inner meaning of the Parmenides is both non-discursive and theurgic. According to Proclus, when Plato is thinking most profoundly he is invariably in agreement with the Chaldaean Oracles,¹¹ the obvious inconsistencies between these two doctrines being resolved on the assumption that Plato is actually concealing his true teaching.¹²

The rational element of philosophical thinking operates by arguing syllogistically on the basis of axioms drawn from the common store of Platonic and Aristotelian notions and then applying the results of these deductive procedures to the doctrines stated in the revealed texts. Moreover, the relation between Proclus’ two main theological texts: the Elements of Theology and the Platonic Theology to a considerable extent reflects this relation between deductive procedure and revealed doctrine. It must be admitted that the parallelism is not complete since, although the Elements of Theology applies deductive method to axioms and practices no formal exegesis of texts, the Platonic Theology practices formal exegesis throughout¹³ but also applies deductive method in various contexts.¹⁴ Nevertheless, treating the Elements of Theology as a model of deductive method and the Platonic Theology as a model of formal exegesis and examining the manner in which the dialectical conclusions of the former work are used to organize the theological systematization of the latter will perhaps provide the illuminating insights into the fundamental structure of Proclus’ theology sought by the present study. It is perhaps of some historical interest to note that in extracting axiomatic material from the Elements of Theology and then using this as a formal template for understanding the exegetical content of the Platonic Theology, we will be following in the footsteps of Proclus himself but running counter to Giovanni Pico della Mirandola. A thousand years after the ancient Greek writer, the “Conclusions according to Proclus” (conclusiones secundum Proclum) section of Pico’s Nine-Hundred Conclusions provides one of the most interesting later readings of the Platonic Theology by using the latter itself as a source of axiomatic material to be applied in the service of a new philosophy.¹⁵

However, the project of extracting axiomatic material from the Elements of Theology and then using this as a formal template for understanding the exegetical content of the Platonic Theology has to begin by making certain strategic decisions. In particular, one must decide what the most important philosophical ideas in the Elements of Theology are and which order for presenting them to the reader is the best. The answers to these two questions are by no means self-evident, since the Elements of Theology consists of a sequence of 211 propositions together with their proofs in which neither are the main axioms distinguished from the other propositions nor are the logical deductions unfolded in a unidirectional sequence.¹⁶ Moreover, the discussion begins by studying the levels of reality in a hierarchy descending from the One, shifts to examining the general principles of causality from different angles and in an order that seems somewhat arbitrary, and then returns to studying the levels of reality from the henads, down through intellects, to souls. The approach of the present chapter will be to use the descending hierarchical structure of the Platonic Theology as an initial guide for organizing the propositions of the Elements of Theology into groups dealing with that hierarchy, and then to introduce the propositions dealing with those general principles of causality stated in the Elements of Theology that seem most relevant to the understanding of each level of reality as one descends.¹⁷ It is important to bear in mind in the course of this reading of the Elements of Theology that Proclus is throughout his treatise pursuing a fundamentally affirmative theology articulated with a discursive method.¹⁸ Therefore, his formulation of propositions about the One or gods simultaneously assumes that these principles transcend the property of unity and the possibility or necessity of demonstration.¹⁹

The discussion of Proclus’ theology through a juxtaposition of his two most relevant texts in the present chapter will be divided into five segments dealing with: the basic module of Proclus’ system (limit, infinity, the mixed); the One (or the monad of the unity series); the henads (or the unity series); Intellect (or the monad of the intellect series); and the intellects (or the intellect series), in each case first considering the axiomatic material in the Elements of Theology and secondly applying this to the exegetical content of the Platonic Theology.²⁰ The structural relation between the order of discussion here proposed for the Elements of Theology and the book division of the Platonic Theology might be tabulated as follows:²¹

Although the nature of Proclus’ theology does lend itself to a systematic exposition of this kind, the reader needs to be alerted to certain complications below the surface of the narrative. In particular, one must realize that the attributes of the different levels of reality from the One downwards in the Platonic Theology are determined according to the narrative sequence of Plato’s Parmenides,²² and that tensions frequently arise between the internal metaphysical “logic” of Proclus’ theological system and the requirement of compliance with the “letter” of this authoritative Platonic text.²³ To mention just one example here, the notions of continuity and similarity that underlie the system from the start (prop. 103) emerge only in one of the subsequent lemmas of the dialogue (147c–d).

Limit, unlimited, and the mixed

A set of propositions dealing with the relations between being, limit, infinity, and power seems to play a particularly important role in the attempt by the Elements of Theology to delineate the whole of reality as a hierarchy of causes and effects. Here Proclus argues that all beings are composed of “limit” (πέρας) and “unlimited” (ἀπειρία) (prop. 89),²⁴ that a First Limit and a First Unlimited subsist in themselves prior to those beings (prop. 90), that the First Unlimited is equivalent to “unlimited power” (ἄπειρος δύναμις) (prop. 91), that the multitude of powers is derived from the First Unlimited (prop. 92), and that the First Unlimited is equivalent to “power-in-itself” (αὐτοδύναμις) (prop. 92, proof). A further proposition – together with its proof – states that primal Being communicates limit and lack of limit to other beings because it is itself the primal “mixed” (μικτόν) of limit and unlimited (prop. 102).

These propositions are themselves framed by two further groups of propositions dealing with notions of participation and of order. In the first group, Proclus argues that there are “unparticipated terms” (ἀμέθεκτα) that produce from themselves “participated terms” (μετεχόμενα) (prop. 23), and that there is a descending order of superiority between unparticipated terms, participated terms, and “participating terms” (μετέχοντα) (prop. 24), these points being illuminated by a previous proposition stating that there will always be an “order” (τάξις) of terms dependent on a “monad” (μονάς) in the cases described (prop. 21). In the second group, Proclus argues that every unparticipated term “qua unparticipated” (ᾗ ἀμέθεκτόν ἐστι) is self-caused (prop. 99), and that every unparticipated term is dependent on the “First Principle of everything” (ἡ μία τῶν πάντων ἀρχή) (prop. 100), these points being clarified by a previous proposition stating that the cause of each order communicates its “distinctive property” (ἰδιότης) to the entire order (prop. 97). A final proposition stating that the first members of any order “have the form of the terms preceding them” (μορφὴν ἔχει τῶν πρὸ αὐτῶν) (prop. 112) completes the picture.

By summarizing the content of the propositions mentioned above, we can arrive at something like a “basic module” of the architectural construct that represents Proclus’ theology. Having assumed that a well-known discussion in Plato’s Philebus applies to the theory of Forms and the principles underlying that theory, Proclus finds a triadic structure which represents at the same time the diffusion of power²⁵ and the formation of being²⁶ to be the ultimate basis of reality. Here, the members of the triad themselves are sometimes called limit, unlimited, and mixed²⁷ and sometimes the unparticipated, [initial] participated, and [further] participated term,²⁸ while the first member of this triad has the ambivalent status²⁹ of being both separate from³⁰ and conjoined with the other terms.³¹ Moreover, this triadic structure corresponds to an unspecified number of terms forming a series derived from a monad.³² The vast complexity of Proclus’ system can, by understanding it as a sequence of rhythmic derivations from the basic module, be reduced to this relatively simple form.

Some preliminary remarks are necessary concerning the “power” (δύναμις) that has already been mentioned and the “activity” (ἐνέργεια) that is closely connected with it.³³ In general, Proclus understands the causal process as involving – from the viewpoint of the cause – a “surplus” (περιουσία) of power in the cause³⁴ from which it “gives something” (δίδωσί τι)³⁵ while “remaining in itself” (μένον ἐφ’ἑαυτοῦ)³⁶ and – from the viewpoint of the effect – the “reception” (ὑποδέχεσθαι) of a power³⁷ which has “become less powerful” (ἐλάττω δύνασθαι)³⁸ according to the “suitability” (ἐπιτηδειότης) of the effect.³⁹ According to Proclus’ theory of causation, the power at the point of emission from the cause is “complete” (τελεία)⁴⁰ and is associated with the cause’s actuality,⁴¹ whereas the power at the point of reception is “incomplete” (ἀτελής)⁴² and associated with the effect’s potentiality.⁴³ However, the Aristotelian principle that the cause “is actually what the effect is potentially” (κατ’ἐνέργειαν ὂν ὃ τοῦτο δυνάμει ἐστίν)⁴⁴ is combined here with the Platonic assumption that the cause, in the proper sense of that term, “is transcendent” (ἐξῄρηται) with respect to the effect.⁴⁵

Power and activity generally occur together in Proclus’ unfolding of the structure of reality.⁴⁶ However, the fact that power tends to be associated more closely with the First Unlimited and activity more closely with the First Mixed included within the fundamental module⁴⁷ leads to important consequences. Having stated in the Elements of Theology that every cause “has activity” (ἐνεργεῖ) that is both prior to and subsequent to its effect,⁴⁸ Proclus explains this proposition in the accompanying proof and corollary by arguing that, given a descending order in which each term is effect of the previous and cause of the subsequent, there is a continuous diminution of power but overlapping extensions of activities.⁴⁹ This situation presumably arises from the disparity between the indeterminacy and the determinacy that power and activity respectively derive from their structural function within the basic module.⁵⁰

The basic module appears as a whole or in part on almost every page of Proclus’ Platonic Theology. It is most explicit in the early chapters of book III, where in the descending hierarchical order of divinity the first group of the so-called intelligible gods is described in detail and a reading of the Philebus obscures the author’s more usual dependence on the Parmenides.⁵¹ The first three principles mentioned here are limit, infinity, and mixed, and Proclus emphasizes that limit and infinity have the ambivalent status of being both transcendent of and coordinate with the mixed,⁵² the point being important because the architectonics of his system depends on a combination of sequencing and subdivision of terms. Although in these early chapters of book III, limit, infinity, and mixed are all described as “henads,”⁵³ the situation becomes more complicated as we read on in Proclus’ treatise. Here, we discover that an analogous triad divides the entire pantheon,⁵⁴ subdivides its three terms into three further terms, and then subdivides these further terms in a similar manner, yielding a basic structure of twenty-seven terms.⁵⁵ The terminology of “intelligible,” “intelligible-and-intellectual,” and “intellectual” most often applied to this primary division is relatively stable.⁵⁶ However, the larger or smaller subdivisions can be characterized as monad, dyad, and triad,⁵⁷ as father, power, and intellect,⁵⁸ as remaining, procession, and reversion,⁵⁹ and as being, life, and intellect.⁶⁰ The choice seems to depend on whether the structure is viewed as dynamic or stable and as a larger or smaller subdivision,⁶¹ although purely exegetical criteria sometimes play a role.⁶²

The relations suggested by the Elements of Theology between the notions of limit, unlimited, and mixed on the one hand and those of participation and order on the other also underlie much of the structuration in the Platonic Theology. However, the precise location of the amethekta (“unparticipated”) terms has been puzzling commentators from at least the time of Nicholas of Methone.⁶³ The problem is basically as follows: If one is confronted with a triad of (e.g.) intelligible, life, and intellect where each term is subdivided into a further triad of intelligible, life, and intellect, is (e.g.) the “unparticipated” intellect the third term of the main division or the third term of the first subdivision? The former option would logically give the unparticipated intellect the most prominent position in the intellectual hierarchy whereas the latter option would with equal logic give it the highest position in that scheme. Proclus’ response to this difficulty is ambivalent. In most cases Proclus refers to the first, second, and third terms of the main division as unparticipated intelligible, unparticipated life, and unparticipated intellect respectively.⁶⁴ However, in certain contexts he is prepared to describe the third term of the first subdivision as the unparticipated intellect.⁶⁵ It is the disparity between these two usages that forces him to countenance the possibilities of speaking of the same term as both unparticipated and participated⁶⁶ and also of a plurality of unparticipated intellects.⁶⁷ Finally, Proclus refers in a more generic way to the entire structure divided into intelligible, life, and intellect as an “unparticipated apportionment” (ἀμέθεκτος μοῖρα).⁶⁸

The unfolding of the structure of reality in terms of the interrelation of power and activity that was so central to the Elements of Theology is also a feature of the Platonic Theology although power and activity tend to be understood more statically as the second and third terms of a triadic structure in the longer work.⁶⁹ The relation between limit and infinity on the one hand and form and matter on the other is the particular topic of chapter 10 of Platonic Theology III. Here, it emerges that both sets of terms represent an opposition of complete power (= activity) and incomplete power (= potentiality), but that the opposition in the case of limit and unlimited covers the entire emanative continuum between complete and incomplete power whereas that in the case of form and matter occurs within that continuum and at a lower level.⁷⁰ The doctrine of the Elements of Theology that, given a descending order in which each term is effect of the previous and cause of the subsequent, there is a continuous diminution of power but overlapping extensions of activities reappears in the Platonic Theology. The axiom itself is restated in chapter 2 of book III⁷¹ and is later applied to the relation between the activities of Zeus-Demiurge in himself and through the lower gods.⁷²

The One or Good

The Elements of Theology begins with a sequence of thirteen propositions that deal explicitly with the first hypostasis of Plotinus’ system, although frequent references to participation show the applicability of the concepts elaborated also to the Platonic Forms and particulars. Within this group, propositions 1–6 relate more closely to the “One” of Plato’s Parmenides⁷³ and propositions 7–12 more closely to the “Good” of Plato’s Republic,⁷⁴ proposition 13 establishing the identity of the One and the Good that is assumed by Plotinus in accordance with Plato’s oral teaching.⁷⁵ There is a danger of misunderstanding the function of this group of propositions. As Proclus explains elsewhere, the terms “One” and “Good” do not denote what is really first or ultimate, since the latter is beyond denotation as such.⁷⁶ Therefore, the sequence of thirteen propositions beginning the Elements of Theology really concerns either the First Limit included in the basic module or – more precisely – the incipient relation between the First Limit, the First Infinity, and the First Mixed.⁷⁷

Propositions 1–6 attempt to demonstrate that the multitude of subsistent things “participates in some manner” (μετέχει πῃ) in unity (prop. 1), that this multitude is both a unity and not a unity (prop. 2), that the multitude “becomes” (γίνεσθαι) a unity by participation (prop. 3), that this multitude – now called “the unified” (τὸ ἡνωμένον) – is other than “the One itself” (τὸ αὐτοέν) (prop. 4), that this multitude is “posterior to” (δεύτερον) the One (prop. 5), and that this multitude consists partly of “unified things” (ἡνωμένα) and partly of “henads” (ἑνάδες) (prop. 6).⁷⁸ With respect to propositions 1–6 the following points are perhaps worth noting. First, terminological distinctions are maintained between unity and the One itself when referring to the One, and between unity of the multitude, the unified, and the henads when referring to things subsequent to the One. Second, the immanent relation between the One and subsequent things in props. 1–4 is complemented by a transcendent relation in prop. 5. Third, the relation between the multitude and unity expressed by the negation “not” is a relation of otherness. Fourth, the static contrast between the non-unity and unity of the multitude in prop. 2 is complemented by a dynamic contrast in prop. 3. Finally, the qualified reference (πῃ) to participation in prop. 1 probably results from the ambivalent status of the first term in the basic module which is unparticipated strictly speaking. Several of the proofs also contain noteworthy points. The proof of prop. 1 is based on the rejection of an infinite regress of terms and therefore distinguishes the One clearly from the infinity of the second term in the basic module. The comment within the proof of prop. 6 that the unifieds participate in the One itself whereas the henads do not so participate again alludes to the ambivalent status of the first term in the basic module.

The next group of propositions begins with a statement of the fundamental assumption underlying Neoplatonic thought: namely, that every cause⁷⁹ is “superior” (κρεῖττον) to its effect (prop. 7).⁸⁰ Further propositions attempt to prove that the Good itself⁸¹ is superior to a multitude of subsistent things that “somehow participate in” (ὁπωσοῦν μετέχει) goodness (prop. 8), and that the Good itself⁸² is superior to that multitude of subsistent things that are specifically “self-sufficient” (αὐτάρκης) (prop. 10).⁸³ This group of propositions continues with a statement of another fundamental assumption underlying Neoplatonic thought: namely that all “existent things” (ὄντα) derive from a single “first cause” (αἰτία πρώτη) (prop. 11). This in its turn leads to the further conclusion that all existent things derive from a first “principle and cause” (ἀρχὴ καὶ αἰτία) that is “the Good” (τὸ ἀγαθόν) (prop. 12). The following points should be noted with respect to propositions 7–12. First, terminological distinctions are maintained between the primal good and the simply good when referring to the Good, and between the self-sufficient and the not self-sufficient when referring to things subsequent to the Good. Second, the arguments about participation and superiority applied to the Good in props. 8 and 10 respectively parallel the similar arguments applied to the One in props. 1 and 5 respectively. Third, the qualified reference (ὁπωσοῦν) to participation in prop. 8 results from the ambivalent status of the first term in the basic module which is strictly speaking unparticipated. Several of the proofs also contain noteworthy points. The proofs of props. 7 and 11 are based on the rejection of an infinite regress of terms and therefore distinguish the Good clearly from the infinity of the second term in the basic module. Comments within the proofs of props. 8 and 9 introduce the notion of the Good’s final causality by referring to the “striving” (ἐφίεσθαι) towards it of subsequent things.

Almost all of these notions are applied at some point in elaborating the complex system of the Platonic Theology, beginning of course with the idea running through the entire text that the gods (as the supreme principles) are equivalent to henads (as the most unitary principles). Here, I simply draw attention to the explicit assumption of the inverse relation between multiplicity and superiority underlying Proclus’ argument from analogy that just as the highest within the orders of souls govern the most simple bodies, and the highest within the intellectual orders govern the most universal souls, so do the highest within the orders of the gods govern the most simple beings.⁸⁴ It is also worth noting that in order to follow the distribution of the properties of unity and goodness through the various divine orders, Proclus is forced to make some complicated maneuvers in his use of concepts and terminologies. With respect to unity, he notes that “infinite multiplicity” (ἄπειρον πλῆθος) occurs in the third triad of the intelligible gods whereas “number” (ἀριθμός) appears in the first triad of the intelligible-and-intellectual divinities, the latter having the additional feature of being “distinct” (διακεκριμένον).⁸⁵ With respect to goodness, Proclus notes that “intelligible goodness” (ἀγαθότης νοητή) occurring in the first triad of the intelligible gods represents a “fullness of divine self-sufficiency and power” (πλήρωμα τῆς θείας αὐταρκείας καὶ τῆς θείας δυνάμεως) which is superior to any “idea” (ἰδέα).⁸⁶ The position with regard to unity results from the dependence of Proclus’ theology on exegesis of the Parmenides, the position with regard to goodness from the same theology’s lack of dependence on exegesis of the Republic.

The henads

In accordance with the system of structural analogies that dominates Proclus’ theology, just as the primal Intellect is followed by secondary intellects, and just as the primal Soul is followed by secondary souls, so is the primal One followed by secondary ones.⁸⁷ The doctrine regarding these secondary ones – usually called “henads” (ἑνάδες) or “gods” (θεοί) – is set out in propositions 113–165 of the Elements of Theology. Its most important features can perhaps be summarized by considering what Proclus has to say first about the status and second about the function of these principles.⁸⁸

The status attributed by the Elements of Theology to the henads is ambivalent in that they are sometimes more closely associated with the One but sometimes more closely associated with beings. The assimilation of the henads to the One is suggested in a few passages where Proclus argues that the entire divine order is “unitary” (ἑνιαῖος),⁸⁹ and that everything divine is “primarily and maximally simple” (ἁπλοῦν πρώτως καὶ μάλιστα),⁹⁰ the clear assumption being that the henads are collectively as well as individually unitary. The assimilation of the henads to beings occurs more frequently although there seems to be a further complication. On the one hand, Proclus argues that, since every plurality nearer to the One is lesser in quantity but greater in power, henads are less numerous than beings;⁹¹ on the other hand, he maintains that, since one henad is participated immediately by one being, the number of participated henads is identical with the number of participating beings.⁹² The explanation of the disparity between these two statements seems to be that the henads are being associated in the former case with phases of the sequential cycle of intellect’s remaining, procession, and reversion – that is, the monadic intellect and the series of intellects – but in the latter case with the subdividing cycle of intellect’s remaining, procession, and reversion – that is, the intellect completing the triad of being, life, intellect.⁹³ I will mark the ambivalent status of the henads by using the graphic form henad(s) to express their closer association with the One and the expression henads-beings to express their closer association with beings.

The function assigned by the Elements of Theology to the henads is to initiate the causality of the universe by conferring on existent things distinctive properties and the interrelation between properties.⁹⁴ The basis of this functionality is the “distinctive property” (ἰδιότης) possessed by each henad, this distinctive property being (a) what defines it as a henad,⁹⁵ (b) what defines it as a henad of a certain type,⁹⁶ and (c) what defines it as this henad.⁹⁷ In accordance with this functionality, the henads confer on beings not only their distinctive properties – since the highest members of each type of being “are referred to the gods so that in every order there are terms analogous with the gods that maintain and preserve the secondary terms”⁹⁸ – but also the interrelation between those properties – since it is through the gods’ agency that “everything is in sympathy with everything else, the secondary things pre-existing in the primary and primary things manifested in the secondary,”⁹⁹ these two functions representing opposing aspects of the henads’ unifying power.¹⁰⁰ Three further aspects of the henads’ function are of particular importance. First, the henads exercise causality while entering into no “relation” (σχέσις) with the beings that they cause.¹⁰¹ However, here one must take account of a distinction between the causal activity of the henad(s) which is transcendent with respect to subsequent beings and the causal activity of the henads-beings which is coordinate with respect to subsequent beings.¹⁰² Second, given that the One and henads subsist prior to Intellect and intellects, the causal activity of the henads can be called “providence” (πρόνοια).¹⁰³ Third, the henads exercise causality through the production of beings that are “self- (αὐτο-) determining principles,” their self-determination implying the threefold cycle of remaining, procession, and reversion in both its subdividing and its sequential forms.¹⁰⁴ It is precisely because of their self-hood that these principles exhibit the greatest affinity to the Good¹⁰⁵ and by implication with the henads also.

Awareness of the henads’ ambivalent status in being associated sometimes more closely with the One and sometimes more closely with beings is crucial to the understanding of the Platonic Theology as a whole.¹⁰⁶ Although a close association of the henads with the One is probably to be assumed throughout book II and occasionally elsewhere,¹⁰⁷ the treatise as a whole implies the complementary association of the henads with beings. This is because the work unfolds predominantly as an exercise in affirmative theology and as an exegesis of the second hypothesis of the Parmenides taking its starting-point from the “one-being” (ἓν ὄν).¹⁰⁸ A passage in chapter 21 of book III where the henad corresponding to the first term of the triad of father, power, and intellect is said to be “intelligible” (νοητόν) on the grounds that deity is inherently participable brings this undercurrent of affirmative theology to the fore.¹⁰⁹

The henads’ role in conferring on existent things distinctive properties and the interrelation between properties is clarified particularly by the discussion of the causality exercised by Zeus/the Demiurge (= the third term of the first triad of intellectual gods).¹¹⁰ Proclus here develops a complicated theory according to which Zeus is said to have a “dyadic character” (τὸ δυοειδές).¹¹¹ This character manifests itself in his relations not only with Kronos and Rhea (= the first and second terms of the first triad of intellectual gods) – as reflected in the accusative cases of his two cultic names: Δία and Ζῆνα¹¹² – but also with a mysterious seventh divinity (= unique term replacing the third triad of intellectual gods).¹¹³ Zeus and/or the seventh divinity is said to be responsible for distinguishing the intellectual order of gods from the preceding and subsequent orders, the terms within the intellectual order from one another, and indeed the status of the discriminatory god himself.¹¹⁴ The process described here is understood to be the meaning of the Chaldaean Oracle that refers to a “flashing with intellectual cuts” (νοεραῖς ἀστράπτουσα τομαῖς),¹¹⁵ although Proclus attempts to confirm this direct revelation by the gods with the passage in the Timaeus referring to the Demiurge’s cutting of the psychic substance into seven portions.¹¹⁶

The various additional aspects of the henads’ function described in the Elements of Theology can also be exemplified in Proclus’ treatment of the intellectual gods in his larger treatise. Thus, exercise of causality while entering into no “relation” (σχέσις) with the beings that they cause is exemplified particularly in the case of the Couretes (= second triad of intellectual gods). These gods¹¹⁷ – who are also called the “immaculate” (ἄχραντοι) gods¹¹⁸ – are said to preserve the status of the divine substance as “unmixed with respect to secondary things” (ἄμικτον…πρὸς τὰ δεύτερα) and also the inflexibility of the divine powers and activities.¹¹⁹ The providence of the henads is illustrated by Proclus’ interpretation of the myth of the Politicus, where the two revolutions of the world are said to represent two activities of Zeus/the Demiurge, namely, the elevation of souls towards intellect, which is under the rule of providence, and their inclination towards nature, which is according to the order of fate.¹²⁰ Exercise of causality through the production of beings that are self-determining principles is exemplified particularly in the cases of Kronos and Zeus (= first and third terms of the first triad of intellectual gods).¹²¹ The god Kronos¹²² is said, by being both dependent on the causality of a prior principle – as its “paternal intellect” (πατρικὸς νοῡς) – and the initiator of causality for subsequent terms – as their “intellectual father” (πατὴρ νοερός)¹²³ – to combine subdividing and sequential activity.¹²⁴

Intellect

In Plotinus’ system, the second hypostasis is “Intellect” (νοῦς). An alteration of the doctrine of first principles by the introduction of “Being” (ὄν) and “Life” (ζωή) as intermediate hypostases between the One and Intellect was sometimes suggested by the late ancient Platonists themselves and has been the subject of much debate among modern scholars.¹²⁵ However, the Plotinian view regarding the “intellective” character of the second hypostasis was essentially maintained by later thinkers. In the Elements of Theology the order of the One and henads is immediately followed by that of Intellect and intellects. Moreover, the fundamental doctrine of causality elaborated there – the next topic to consider in any account of Proclus’ theology – makes little sense outside an intellective context. In fact, this doctrine represents probably the most complete expression of the basic module.

Several propositions in the Elements of Theology deal with the role of “similarity” (ὁμοιότης). Thus, “Every procession is accomplished through the similarity of secondary to primary terms,”¹²⁶ and “Every reversion is accomplished through the similarity of the reverting terms to that to which they revert.”¹²⁷ Another proposition in the same treatise emphasizes the notion of “wholeness” (ὁλότης). Thus, “Every series of wholes is referable to an unparticipated principle and cause.”¹²⁸ A connection between the notions of similarity and wholeness is established by a proposition and proof explaining the similarity between the higher principles as a combination of sameness and otherness,¹²⁹ and by a further proposition explaining the relation between all existents as a combination of either (a) sameness and difference or (b) whole and part.¹³⁰ Underlying all these statements is an implicit assumption of the connection between mind and hermeneutics. As a general rule, similarity is not a logical category but a hermeneutic category. Moreover, the Elements of Theology makes extensive use of a threefold distinction between wholes “before the parts” (πρὸ τῶν μερῶν), “of the parts” (ἐκ τῶν μερῶν), and “in the part” (ἐν τῷ μέρει)¹³¹ depending on a process of “designation by a mark” (χαρακτηρίζεσθαι) and the isolation of “the predominant feature” (τὸ ἐπικρατοῦν),¹³² both of which require an interpretive act. Therefore, wholeness is also a hermeneutic rather than a logical category in this context. But, if Proclus posits such an essential connection between the causal and hermeneutic processes, we should not be surprised to find that his notion of causality implies a degree of mind-dependence.

The clearest synthesis of Proclus’ ideas concerning similarity and wholeness is perhaps to be found in his proposition – one of the most important in the Elements of Theology – that “all things are in all things, but in each according to its proper nature” (πάντα ἐν πᾶσιν, οἰκείως δὲ ἐν ἑκάστῳ).¹³³ This synthesis is fully elaborated in the propositions dealing with the order of Intellect and intellects.¹³⁴ However, it also underlies the various propositions concerning the “intellective Forms” (νοερὰ εἴδη).¹³⁵ For Proclus, every intellect is a plenitude of Forms,¹³⁶ although – since the continuum between unity and multitude is also that between complete and incomplete power – the highest Intellect is at least in theory equivalent to a single Form.¹³⁷

The points that we have been considering are important underlying assumptions of Proclus’ doctrine of causality. However, the most visible feature of that doctrine is the triad of “remaining” (μονή), “procession” (πρόοδος), and “reversion” (ἐπιστροφή) that this later Platonist uses in order to replace the two-directional motion by which Intellect is produced from the One in Plotinus’ system, this triad being the most common expression of the basic module in the Elements of Theology.¹³⁸ That a kind of cycle is involved emerges from the proposition: “Everything that proceeds from any principle and reverts has a cyclic activity,”¹³⁹ the cycle resulting from the fact that whatever proceeds does so from a principle to which it also reverts¹⁴⁰ and whatever reverts does so to a principle from which it also proceeds.¹⁴¹ That the cycle embodies a threefold distinction emerges from the proposition: “Every effect remains in its cause, proceeds from it, and reverts to it.”¹⁴² Now, Proclus’ explanation of the nature of each of the three moments within the cyclic process presents certain problems.¹⁴³ The nature of the relation between remaining and procession is clarified when he comments in one of the proofs that what is produced remains in its producer “to the extent that it has an element of sameness” (ᾗ μὲν ἄρα ταὐτόν τι) with it and proceeds from its producer “to the extent that it has an element of otherness” (ᾗ δὲ ἕτερον).¹⁴⁴ In other words, two opposing logical relations of sameness and otherness ground the first two moments of the causal cycle.¹⁴⁵ However, the nature of the relation between procession and reversion is more obscure, given that both moments are associated with the non-logical relation of similarity.¹⁴⁶ The differences seem to be that (a) reversion alone is associated with “appetite” (ὄρεξις);¹⁴⁷ (b) as relations, procession has a downward direction and reversion an upward direction;¹⁴⁸ (c) as powers, procession is in transition to incompleteness and reversion in transition to completeness;¹⁴⁹ and (d) reversion alone cannot be expressed in strictly logical terms.

Given that the triad of remaining, procession, and reversion is the most common expression of the basic module, it occurs within Proclus’ system not only as a single structure but also as a multiplicity of structures. With respect to the latter, one proposition of the Elements of Theology states that “Everything that proceeds from a multitude of causes passes through the same number of terms in reverting as in proceeding,”¹⁵⁰ and the proof of another proposition that “there are greater and lesser cycles, some reversions being to immediately prior terms, and some to the higher, right up to the principle of all things.”¹⁵¹ The multiple structure is normally configured as a monad and a series of terms to which the threefold cycle is applied in either a “subdividing” or a “sequential” form.¹⁵² The subdividing version of the cycle – where the remaining, procession, and reversion within the cycle can each be articulated into a further remaining, procession, and reversion – is indicated in the situation where intellect knows “the prior to itself” (τὰ πρὸ αὐτοῦ) and thereby “itself” (ἑαυτόν).¹⁵³ The sequential version of the cycle – where the cycle of remaining, procession, and reversion is followed by a further cycle of remaining, procession, and reversion – is assumed in two cases:¹⁵⁴ namely, where a primary Intellect, primary Soul, and primary Nature are connected as monads of separate series,¹⁵⁵ and where a primary Intellect and secondary intellect(s)¹⁵⁶ are connected as monad and non-monadic term(s) within a single series.¹⁵⁷ With respect to the subdividing and sequential cycles, it should be noted that (a) the progressions of terms in both cases involve a gradual lowering of their status;¹⁵⁸ (b) the primary distinction between the two cycles is based on the reversion which has to precede any further articulation in the sequential but not in the subdividing version;¹⁵⁹ and (c) the two progressions of terms can be combined or even translated into one another.

Proclus’ elaboration of a theory of causality based on certain underlying assumptions regarding similarity and wholeness provides a good illustration of the tension between the internal metaphysical logic of his theological system and the requirement of compliance with the letter of an authoritative Platonic text. Now, it is undeniable that the notions of similarity and wholeness are equally fundamental to Proclus’ theory of causation. However, although wholeness is an attribute of one of the highest levels of divinity (the second triad of the intelligible gods), is mentioned in one of the earlier lemmata of the Parmenides’ second hypothesis (at 142c–d), and is discussed in book III of the Platonic Theology,¹⁶⁰ similarity and dissimilarity are attributes of a much lower level of the divine world (the hypercosmic gods), are only mentioned in a later lemma of the second hypothesis (at 147c–d), and are not discussed until Platonic Theology VI.¹⁶¹

The triad of remaining, procession, and reversion that is the most visible feature of Proclus’ theory of causation and is the most common expression of the basic module from which his system is constructed provides an illustration of the ingenuity with which the later Platonist often responds to the kind of tension between metaphysical and exegetical requirements just mentioned. In actual fact, the first two moments of the triad¹⁶² constitute an expression of the “Greatest Kinds” (μέγιστα γένη) that represent the theory of Forms in Plato’s Sophist and enter into the composition of soul in his Timaeus, given that any effect remains in its cause in a moment of “rest” (στάσις) and “sameness” (ταυτότης) and proceeds from its cause in a moment of “motion” (κίνησις) and “otherness” (ἑτερότης). From the Platonic Theology we discover that all five genē¹⁶³ are distributed in different ways throughout the orders of intelligible, intelligible-and-intellectual, and intellectual gods. Thus, (1) in the first triad of intelligible gods there is being; in the middle triad, motion and rest – since the “eternity” (αἰών) that “remains” (μένει) in the One¹⁶⁴ is located there; and in the last triad, sameness and difference; (2) in the first triad of the intelligible-and-intellectual gods there is being – colorless, shapeless, and intangible in nature;¹⁶⁵ in the middle triad, motion and rest; and in the last triad, sameness and difference; (3) in the first triad of the intellectual gods there is being; in the middle triad, motion and rest; and in the last monad, sameness and difference – since distinction by means of “intellectual cuts” (νοεραὶ τομαί) occurs there.¹⁶⁶ Proclus explains that the five kinds are present everywhere but not everywhere in the same manner in accordance with the principles of similarity and wholeness. It is not until the third monad of the intellectual sphere that “all the kinds and forms first blaze forth” (πρῶτον μὲν ἐκλάμπει τὰ γένη πάντα καὶ τὰ εἴδη) because this level is “primarily characterized” (μάλιστα χαρακτηρίζεται) by otherness, has allotted to it the lower boundary of the universal hypostases, and is the source from which the “participated intellect” (μετεχόμενος νοῦς) and the multi-formed orders of souls proceed.¹⁶⁷ However, the manner in which Proclus locates the Greatest Kinds within his system broadly parallels that in which he locates the Forms in general. As required by the exegesis of the Timaeus, the Forms are manifested in a more unitary way in the Intelligible Living Creature (= the third triad of the intelligible gods)¹⁶⁸ and in a more divided way in the Demiurge (= the third term of the first triad of the intellectual gods).¹⁶⁹

If the Elements of Theology treats the triad of remaining, procession, and reversion either as a single structure or as a multiple structure and, when it is a multiple structure, either in a “subdividing” or a “sequential” form, the Platonic Theology – as we have already noted more generally in connection with the expansion of the basic module, and more specifically in connection with the transcendence and immanence of limit, infinity, and mixture and with the exemplification of self-determination by Kronos and Zeus – tends to present the triad predominantly in its multiple and subdividing form.¹⁷⁰ This is presumably because the multiple and sequential form becomes more significant only after the transition has taken place from the universal and unparticipated to the partial and participated ranks of intellects and souls and this, strictly speaking, falls outside the subject matter of the Platonic Theology.

Intellects

Throughout the Elements of Theology the level of reality corresponding to Plotinus’ second hypostasis is conceived of as a monadic Intellect and a series of intellects dependent upon it, the resulting structure being configured in accordance with the basic module and articulated further through an application of the threefold cycle of remaining, procession, and reversion in its sequential form. A sequence of eighteen propositions is devoted specifically to this topic. Among these, prop. 166 distinguishes the unparticipated Intellect from the participated intellects; props. 167–180 describe the characteristics of intellects in general – props. 176–178 being an insertion dealing with the relation between intellects and Forms; and props. 181–183 classify participated intellects according to the lower principles that participate them. More rarely in the Elements of Theology the level of reality corresponding to Plotinus’ second hypostasis is conceived of as an evol-ving triad of being, life, and intellect, the resulting structure again being configured in accordance with the basic module and articulated further through an application of the threefold cycle of remaining, procession, and reversion in its subdividing form.¹⁷¹

At first sight, the very positing of a triad of “being” (ὄν), “life” (ζωή), and “intellect” (νοῦς) seems to call into question what we have termed the intellective character of all causality in Proclus. Now, it is true that being seems to be contrasted as a first term with intellect as a third term when the later Platonist argues that “All things participating intellect are dependent on unparticipated Intellect, those participating life on unparticipated Life, and those participating being on unparticipated Being. Among these terms, Being is prior to Life, and Life to Intellect.”¹⁷² The same conclusion can be drawn when he argues that “Unparticipated terms subsist prior to participated terms. So that Being that is in itself and in an unparticipated manner must exist prior to the being that is conjoined with intellect, since the former is intelligible not as coordinated with Intellect but as perfecting it in a transcendent way.”¹⁷³ However, a number of considerations point to the fact that Being cannot in the last analysis be separated from Intellect in a totally non-intellective sense.¹⁷⁴ First, Proclus argues for the conclusion that every intellect has its substance, power, and activity in eternity from the premise that the intelligible, intellection, and intellect are “identical” (ταὐτόν).¹⁷⁵ Second, he clearly identifies the being of the triad of Being, Life, and Intellect with the “intelligible” (νοητόν) of the Intellect. This leads to the further consequences that (a) Intellect and its intelligible are “one in number” (ἓν κατ’ ἀριθμόν) or else simply “the same” (ταὐτόν);¹⁷⁶ (b) it is possible to speak of the first in the series as “the intelligible intellect” (νοῦς νοητός);¹⁷⁷ and (c) the intelligible of the Intellect is identified with that “essence” (εἶναι) of Intellect in the context where it produces subsequent things “by being what it is” (κατὰ τὸ εἶναι ὅ ἐστι).¹⁷⁸

This intellective character of all causality is confirmed on the basis of the Platonic Theology not only through the prominence of the main triad of intelligible, intelligible-and-intellectual, and intellectual gods throughout the text but also by Proclus’ normal preference for speaking of the triad of “intelligible” (νοητόν), life, and intellect rather than that of “being” (ὄν, οὐσία), life, and intellect.¹⁷⁹ Passages referring to the henads as intelligibles point to the same conclusion.¹⁸⁰ Moreover, certain general metaphysical principles underpinning Proclus’ theological system such as the dependence of reversion upon the hermeneutical category of “similarity” (ὁμοιότης) imply that causality is at least partially mind-dependent. That there is an irreducibly idealistic element in Proclus’ theology is not surprising when the historical evolution of the latter is considered, since the hierarchy of gods disclosed by the second hypothesis of the Parmenides and forming the ground plan of the Platonic Theology is clearly a subdivision of rather than an addition to the Plotinian hypostasis of Intellect. Medieval readers of Proclus such as Dietrich of Freiberg, Berthold of Moosburg, and Nicholas of Cusa were therefore correct in understanding their source in this manner, despite the frailty of the textual tradition on which their interpretation had to depend.