BMCR 2018.01.16

All from One. A Guide to Proclus

, , All from One. A Guide to Proclus. Oxford; New York: Oxford University Press, 2017. xiii, 418; 4 p. of plates. ISBN 9780199640331. £70.00.

[Authors and titles are listed at the end of the review.]

The book is the upshot of an effort to offer a systematic and general overview of the main facets of Proclus’ philosophy. Unlike some other introductory volumes, this book covers all the crucial aspects of Proclus’ thought, from logic to theurgy. As an overall impression, one might say that many of the papers present the cutting edge of scholarship on Proclus.

A biography of Proclus, by Christian Wildberg, emphasizes some points that were hitherto in the background of scholarship, among others, the so-called ‘House of Proclus’. Discussing Proclus’ relationship with the Christian authorities, Wildberg raises the possibility that the treatise detailing eighteen arguments for the eternity of the world can be read as a contribution to the intra-Platonic debate on the right interpretation of the Timaeus.

Proclus’ role in the Platonist tradition is examined by Harold Tarrant, with specific reference to the commentary tradition. The use of allegorical exegesis in reading Plato required a response to passages where Plato seems to reject the use of allegory. One of the most illuminating points in the paper is the discussion of the hermeneutical constraints Proclus had to face in commenting on Plato’s dialogues. By insisting that a single system of truth could be found in all inspired authors, Proclus could use these authors to constrain his exegesis and avoid unbridled speculation.

But what does it mean for an author to have a system? Marije Martijn and Lloyd P. Gerson approach the problem by introducing the notion of Ur-Platonism, familiar from Gerson’s previous work.1 On that account, there are five basic features of Platonism (anti-materialism, anti-mechanism, anti-nominalism, anti-relativism and anti-skepticism) which constitute an explanatory framework within which the physical can be related to its intelligible causes. Presentation of an entirely coherent and comprehensive explanation of reality requires connecting the ontologically inferior with the ontologically superior: the many with the One, and the sensible with the intelligible. The authors argue that Proclus’ systematicity suffered from disadvantages, and that his rigid adherence to some of the principles led him to postulate entities that are difficult to explain thereafter.

In Gerd van Riel’s clear discussion of the highest principles, the One comprises both ineffability and causality, thus expressing contradictory features. The contradiction is mitigated by the thesis that the One is a cause ex effectibus only. Proclus’ triadic structure of being-life-intellect is used to characterize not only the self-constitution of being, which proceeds through life in order to revert to its origin in the act of thinking that constitutes the demiurgic intellect, but also the self-constitution of each particular being. Proclus’ ontological hierarchy is further analyzed by Pieter d’Hoine with reference to Proclus’ reading of the Parmenides : Proclus’ introduction of the various levels of ideas/forms serves to solve the first two aporiai raised in that dialogue, which are concerned with participation.

Both the world soul and the individual soul play a crucial role in the whole system, and John Finamore and Emily Kutash examine the subtle divisions in Proclus’ hierarchy of souls and their relation to number. The supposition of a hypercosmic World-Soul mediates leads Proclus to argue that its hypercosmic aspect mediated between the hypercosmic Monad of Soul and a plurality of hypercosmic souls. The authors also draw attention to the deep difference between the notion of the individual soul in Aristotle and Proclus; while the former connects imperishability to circular motion, the latter attributes it to the contact of Soul with the Intellect.2

Understandably, Proclus’ description of the physical world owes much to the Timaeus. Jan Opsomer stresses that this dialogue is interpreted as giving a hypothetical picture of physical nature, which is characterized with a degree of indeterminacy and lacking the perfection that its causes have. Genuine causes are incorporeal ( El. Theol. § 80), just like qualities. Most interesting is the discussion of ‘geometric atomism’ according to which corpuscles making up the elements are determined by geometric forms (the Platonic bodies), although one single geometric particle is not a token of the element in question.3

Obviously, mathematics was very much tied to the study of nature, but Dominic O’Meara also stresses Proclus’ interest in the application of mathematics to practical philosophy, in regulating the life of the city or producing harmony in our moral character. In more technical matters, there is an emphasis on the two aspects of his interpretation of geometrical thinking ( in Eucl. 178.9-179.9, 203.1-5). The difference corresponds to the difference between axioms and postulates; drawing on axioms the geometer develops theorems whereas postulates leads him developing problems. This is derived from Euclid’s text, according to which there is a difference between (a) the demonstration of consequences arising from prior causes and (b) the construction of figures in φαντασία from what is given to διάνοια (discursive reason).4

In his discussion of epistemology, Christoph Helmig shows that Proclus makes use of two kinds of dialectic, one applying Aristotelian syllogistic, the other being equivalent to Plato’s procedure of division, definition, demonstration and analysis. Names are supposed to have two functions, teaching and dividing, and, Helmig argues, they do not exist only in the human soul, i.e. are not merely conventional. He also notes that Proclus’ theory set the rules for most later Neoplatonic approaches.

Theology is central to Proclus’ oeuvre. As he interpreted Plato’s doctrines to harmonize with the religious background against which they were developed, Proclus had to incorporate pagan religious tradition, myths and practices alike, into his own philosophy. Luc Brisson lays great emphasis on his effort to align Plato’s teachings with other theologies, especially the Greek theology associated with Orphic mysteries and Chaldean oracles. Proclus’ effort results in a very elaborate layering of the whole philosophical edifice. Theurgy offers a more specific starting point. Robbert van den Berg stresses that Proclus clearly understands theurgy in opposition to theology, for while the latter deals in λόγοι, the former is about ἔργα. Any account of theurgic practices must be connected to a theory of causation; there is a link of sympathy between divine causes and lower beings, such as animals and plants, which can be put to proper use when priests pay attention to their sympathetic relation with higher-order beings. The practice of theurgy gains further significance when accompanied by Proclus’ rejection of Plotinus’ thesis of the undescended human soul, because in this way we need further assistance to ascend back to our original state. Moreover, theurgic power is linked to faith (πίστις), which is beyond knowledge.

One aim of theurgic rituals is to neutralize evil, whose existence in the world is hard to explain. Proclus was absorbed with the problem throughout his career, and Carlos Steel examines his views as expounded particularly in the Tria Opuscula. The reality of evil in a providentially organised world cannot be due to divinity; it comes from the inferior nature of a type of being that has the possibility of failure. Steel points out that Proclus never attempts to connect the two levels on which evil occurs: that of particular souls and that of particular bodies. The mode in which evil exists is not independent, rather is it parasitic insofar as it is not intended by nature or related by nature to the agent. He also stresses that it is wrong to connect the Neoplatonic theory of evil with the theory of privation without qualification. Evil is not a privation of a substantial form, although can be taken as a privation of the perfection that a being is supposed to have.

It is most welcome that the volume contains a paper discussing Proclus’ views on the peculiar character of human life. Dirk Baltzly concentrates on Proclus’ notion of our highest aim, assimilation to God, on the grades of virtues and their role in philosophical curriculum, and on political philosophy. Because Proclus rejected the doctrine of the undescended human soul, he regarded assimilation as becoming like the divinities that are causally closer to the sensible world. The seven grades of virtues express stages in the process towards such divinities. Proclus also says ( in Remp. i. 12.26-13.6 Kroll) that each cardinal virtue is present in each grade. As to politics: Proclus thinks that a well-ordered political community is an image of the cosmos. This is common Neoplatonic doctrine; but Proclus’ alignment of three demiurges, Zeus, Dionysus and Adonis, as progressively less unified paradigms for the ideal polis is a novelty, and Proclus himself, Baltzly suggests, plays the role of an Adonis-type of statesman engaged in a kind of remedial activity in this world.

In examining Proclus’ literary theory, Anne Sheppard points out that he connects μίμησις with ἐνάργεια and φαντασία (in the sense of visualization). This connection explains his interest in statues of the gods and in visual art in general. Because of their connection to the divine, statues have to be viewed not from an exclusively ‘aesthetic’ point of view, just as beauty cannot be regarded as something which is simply ‘aesthetic’. Sheppard draws attention to the discussion of beauty in the Timaeus -commentary (i. 330.20-334.27), with the peculiar terminology (καλλονή) which suggests that the highest beauty is at the same level as the Good. In short, allegorical interpretation of artistic objects and texts is needed, for there is an analogy between the world and a book; the world can be read as a book containing signs of the higher realm.5

Peter Adamson and Filip Karfík examine the legacy of Proclus. It is a fairly long story in which only a few stages can be emphasized. Damascius’ divergences and Philoponus’ objections receive appropriate attention, as does Proclus’ influence on Pseudo-Dionysius. The discussion of the Arabic reception is especially helpful, since it includes developments later than the al-Kindi circle to which we owe the preliminary version of the Liber de causis, a text that Thomas Aquinas was eager to reconcile with Christian teaching (which led him to deny that we should take the thesis that the intellect creates the substance of the soul literally: 3.22). As for Proclus’ medieval reception, the authors stress that the Elements of Theology was the dominant text and that Proclus was read frequently in the light of Pseudo-Dionysius. The analysis of the reception in the Renaissance is centred on the history of transmission and translation of the texts and on the work of three philosophers, Cusanus, Ficino and Patrizi. Particularly interesting is the survey of Proclean elements in early modern science, especially in Kepler.6

The volume contains plates (e.g. on ‘Proclus’ house’) and closes with appendices (a table of Proclus’ metaphysical system and a list of his works with editions and translations), an extensive bibliography and three indices (of modern authors, passages and subjects). A most useful tool.

Authors and titles

1. Proclus of Athens: A Life, Christian Wildberg
2. Proclus’ Place in the Platonic Tradition, Harold Tarrant
3. Proclus’ System, Marije Martjin & Lloyd P. Gerson
4. The One, the Henads, and the Principles, Gerd Van Riel
5. Platonic Forms and the Triad of Being, Life, and Intellect, Pieter d’Hoine
6. Proclus on the psyche: World Soul and Individual Soul, John Finamore & Emilie Kutash
7. The Natural World, Jan Opsomer
8. Mathematics and the Sciences, Dominic O’Meara
9. Proclus on Epistemology, Language, and Logic, Christoph Helmig
10. Proclus on Gods and Demons, Luc Brisson
11. Theurgy in the Context of Proclus’ Philosophy, Robbert M. van den Berg
12. Providence and Evil, Carlos Steel
13. The Human Life, Dirk Baltzly
14. Literary Theory and Aesthetics, Anne Sheppard
15. Proclus’ Legacy, Peter Adamson & Filip Karfík.


1. Lloyd P. Gerson, From Plato to Platonism. Ithaca; London: Cornell University Press, 2013.

2. Here one might note that Proclus uses the metaphor of circle to describe how the soul imitates the activity of the Intellect and the intellective life, see in Tim. ii. 94.20-2 Diehl.

3. More on this, see J. Opsomer, ‘In Defense of Geometric Atomism: Explaining Elemental Properties’ in. C. Horn and J. Wilberding (eds.), Neoplatonism and the Philosophy of Nature (Oxford: Oxford University Press, 2012), 147-73.

4. One might wonder about the range of his mathematical (sometimes arithmological) knowledge or about the way he uses it. There is not much trace of the geometrical theory of Pappus († c. 350 AD) or of Ptolemy in Proclus, for instance, and it would be interesting to see why.

5. For an important general survey of the book-world relation, see H. Blumenberg, Die Lesbarkeit der Welt (Frankfurt: Suhrkamp, 1983) 2, on late antiquity esp. 42-6.

6. One may add the mathematician Cardano as well, see A. Grafton, Cardano’s Cosmos. The Worlds and Works of an Italian Astrologer (Princeton: Princeton University Press, 1999).