THE BACKGROUND
“Substance” stands for the Greek ousia.1 The philosophical meaning of ousia is that of a primary kind of being which is opposed to what “is” in a secondary or derivative sense. Hence Plato’s Forms are characterized as ousia (as opposed to their sensible copies) and the same holds for Aristotle’s first category (as opposed to the secondary categories which depend on ousia). The Stoics too adopted the notion of ousia and applied it to the material passive principle (as opposed to the logos). This is a very sketchy description and raises several thorny issues. Saying that ousia is a primary kind of being in fact leaves open the question of which criteria to adopt in order to define priority. Ousia might be taken to be prior in so far as it is a primary subject for all other things (and this would clearly privilege matter as a candidate for primary substancehood), or rather a primary and self-subsistent principle of motion (such as Aristotle’s unmoved mover), or again a primary formal cause within the structure of corporeal beings (such as Aristotle’s hylomorphic form) or, finally, a primary stable and invariant essence that is separate from its physical instantiations (such as Plato’s Ideas). The philosophical interest of the Neoplatonic debates on “substance” lies in their highly creative incorporation of these questions within the distinctive framework of late antique gradualist metaphysics.
Furthermore, “priority” is not the only problematic issue at stake, as the very notion of “being” in ancient philosophy is contentious. It is controversial whether we should identify Plato’s ousia with what exists primarily (this would involve the controversial notion of degrees of existence) or rather with what is F in a primary (i.e. stable and invariant) sense. A possible way out from this difficulty would be that of regarding the very distinction between “to exist” and “to be F” (something like the later scholastic distinction between existence and essence) as inadequate for grasping how ancient philosophers, and Plato in particular, conceived of “being”: for the ancient way of understanding “being” entails that “existence” is always “being something” and that there is no concept of existence as such for subjects of indeterminate nature.2 When we come to Aristotle, the issue becomes even more puzzling because different accounts of ousia co-exist in his corpus. In the Categories, Aristotle presents the particular subjects of properties (e.g. the individual human being, the individual horse) as primary ousiai. Furthermore, he does not mention the distinction between form and matter and conceives of universal species and genera (e.g. human being, animal) as secondary ousiai (Cat. 5.2a11–19). In the Metaphysics, instead, form is regarded as primary ousia within a hylomorphic account of physical realities. Unlike what happens in the Categories, substancehood and subjecthood are no longer straightforwardly equated in the Metaphysics (Metaph. 1029a7–b30). In the Metaphysics form is that which makes a composite substance what it is. Hence form can be seen as primary substance (Metaph. 1037a28–30), even if it is in matter and cannot exist apart from it. In turn, the Stoics identified ousia with the passive cosmic material and unqualified principle (Diogenes Laertius 7.134 [SVF I.85] and 150 [SVF I.87]). This was probably a polemical move against Plato and Aristotle’s previous identification of ousia with form: the very concept of eidos has no place in Stoic corporealist ontology.
It was necessary to recall this intricate background since late antique views on ousia can only be properly assessed against the previous tradition; and this is hardly surprising given the overall exegetical character of late antique philosophical debates. Plotinus’ tripartite treatise On the Genera of Being (VI.1–3[42–4]) laid the basis for subsequent accounts.3 In the first part of his treatise Plotinus provides a critical overview of the Peripatetic (Enn. VI.1[42].1–24) and Stoic (Enn. VI.1[42].25–30) theories of categories. The second part (Enn. VI.2[43]) contains an account of the intelligible genera (being, movement, rest, identity and difference), which illustrates Plotinus’ distinctive interpretation of Plato’s Sophist. The third part (Enn. VI.3[44]) focuses on genera in the sensible world and Plotinus’ discussion is again full of references and allusions to the previous tradition (in particular to Peripatetic theories). Plato, Aristotle and the Stoics, then, provide the background of Plotinus’ account, but further aspects should be considered. No philosopher later than Epicurus is mentioned in the Enneads, although Plotinus was fully aware of the post-Hellenistic debates on Plato and Aristotle. Porphyry (Plot. 14.4–14) reports that commentaries on Plato and Aristotle were read in Plotinus’ school and recent scholarship has increasingly shown that Plotinus’ views are based not only on Plato and Aristotle, but on the readings of Plato and Aristotle developed from the first century BCE onwards.
Simplicius connects Plotinus’ critical account of Aristotle’s categories with that of two previous interpreters: Lucius (a very enigmatic figure whose identity and chronology are still an open question) and Nicostratus (whom scholars from Praechter onwards have identified as the second-century Platonic philosopher mentioned in a Delphian inscription).4 At in Cat. 73.15–28, Simplicius says that Lucius, Nicostratus and Plotinus raised objections against Aristotle’s list of categories (genera), since it is unclear whether it is meant to apply to sensible objects alone, or to all beings.5 This remark is further expanded: either the intelligible and the sensible genera are the same, or they are partly the same and partly different. If the genera are different, Aristotle’s list is incomplete, for it omits intelligible beings; if instead the genera are the same, we should assume that intelligible and sensible items are synonymous (i.e. that they share the same name and essence: see Aristotle, Cat. 1a6–12). But this cannot be the case, for intelligible and sensible items form an ordered series where the intelligibles are prior (in so far as they serve as models), whereas the sensibles are posterior (in so far as they are copies). Members of such series do not share the same essence and therefore cannot be species under the same genus.6 Aristotle’s division, however, cannot be rescued by resorting to the other hypothesis either, for if the genera are homonymous (i.e. if they are applied to intelligible beings in a sense different from that which pertains to sensible objects), Aristotle’s division is incomplete, since he did not specifically address the question of the intelligibles. Furthermore, it would be odd to find genera such as paschein and pros ti in the intelligible world (for these genera appear to be incompatible with the distinctive mode of being of intelligible, per se existent and incorporeal beings). Perhaps only some genera in Aristotle’s list apply to both the intelligible and the sensible world, whereas others are peculiar to one ontic level – yet Aristotle did not make this distinction (Simplicius, in Cat. 73.26–7). Apart from some details, the lines from Simplicius just paraphrased closely correspond to Plotinus’ overture in Enn. VI.1[42].1, where after explaining that his discussion will be focusing on beings and their principal divisions, he addresses his general criticism to Aristotle’s list of categories (note however that Plotinus does not mention Aristotle, but refers to a group of philosophers: this might suggest that Plotinus’ target is Aristotle and his interpreters). The conclusion drawn by Plotinus is identical to that in Simplicius: his opponents’ list of genera cannot be seen as an exhaustive division of beings, for they omitted intelligible beings (Enn. VI.1[42].1.30: ta malista onta paraleloipasi).7
Ousia occurs both in Plotinus and in Simplicius (see Simplicius, in Cat. 73.20; Plot. Enn. VI.1[42].1.24, 26), but it is doubtful whether it refers to substance here. For this puzzle is not limited to ousia/substance as the primary kind of being, but rather refers to the essence or nature proper to items in each category (hence not only to substance, the primary genus, but also to quality, quantity, etc.). This broad sense of ousia should not be confused with its narrower sense as primary being. A rigid distinction between the two senses, however, would not be completely justified either. For when Plotinus argues that “it would be absurd for ousia to mean the same thing when applied to primary beings and those which come after them” (Enn. VI.1[41].1.26–7), his words can also easily be read as referring to ousia as primary being. Plotinus would then be suggesting that ousia (i.e. that which “is” primarily – see the remarks above) cannot be a unique genus that covers both intelligible and sensible items. In Ti. 27d Plato describes the sensible realm as that which becomes, but never is, and Platonists before Plotinus sometimes hesitated to apply the term ousia to the world of bodies: for ousia as such is intelligible (ousia noete: see Plut., Def. Orac. 428B–C) (see Dörrie & Baltes 1987–2008: vol. 4, sections 103.0a–103.4). As we shall see below, in the Genera of Being Plotinus develops this position and argues that ousia is only properly referred to intelligible being, whereas what is improperly called ousia in the sensible realm does not satisfy the requirements of primary being and hence is ousia only homonymously.8
Ousia refers unambiguously to Aristotle’s first genus/category in another puzzle that Simplicius ascribes to Nicostratus and Plotinus at in Cat. 76.13–17 (see VI.1[42].2.2–8). Again, both Nicostratus and Plotinus are said to raise an objection against the view that ousia is a single genus. For if ousia were a common genus over sensible and intelligible items, this genus would be prior to them and predicated of both. Hence ousia would be neither incorporeal nor corporeal, for otherwise what is corporeal would also be incorporeal and vice versa. The only way to make sense of this argument is to regard the highest genera as beings (i.e. the most general beings that comprise all existing items under them), and “corporeal” and “incorporeal” as mutually exclusive and jointly exhaustive properties of beings. Given these premises, a highest genus has to be either incorporeal or corporeal: tertium non datur. But this does not really suffice, because Nicostratus and Plotinus further suggest that an incorporeal genus cannot be predicated of sensible items and that a corporeal genus cannot be predicated of intelligible items. Hence ousia cannot be a single genus over intelligible and sensible entities. It is not easy to see why this should be the case, for qualities predicated of bodies were commonly regarded as incorporeal by both Platonic and Peripatetic philosophers (who diverged from the Stoics on this issue): accordingly, there would be nothing strange in predicating an incorporeal genus of a body. In order to rescue Nicostratus’ objection, we might perhaps suppose that the “incorporeal” versus “corporeal” dichotomy was a cursory way of referring to a more sophisticated alternative opposing separate incorporeal (i.e. intelligible) beings on the one side and both bodies and their immanent incorporeal features on the other side. The distinction between separate and immanent incorporeals is fully developed by Porphyry, but traces of it can also be found in the previous tradition; hence it could well be in the background of Nicostratus and Plotinus’ discussions.9 If sensible genera (those predicated of bodies) are conceived of as immanent incorporeals, whereas intelligible genera are regarded as separate incorporeals, then a highest genus predicated of both sensible and intelligible items should be neither a body (for according to Platonic and Peripatetic philosophers bodies are not predicated of anything), nor an immanent incorporeal (for immanent incorporeals are predicated of sensible items, but not of intelligible ones); nor should it be a separate incorporeal being (for separate incorporeals are not predicated of bodies), something which would be quite impossible. This interpretation would perhaps rescue Nicostratus and Plotinus’ objection, but it remains speculative.
Whatever might be the case, Nicostratus and Plotinus’ overall approach is sufficiently clear: Aristotle’s general division of genera/categories, and Aristotle’s ousia as the primary genus in this division, are assessed against the Platonic metaphysical distinction between the intelligible and the sensible world. This critical approach can be seen as a predictable Platonic criticism that opposes Plato’s “two world theory” to Aristotle’s views on sensible substance and categories (see J. Barnes 2005: 43–8). This conclusion, however, requires further qualifications. It is worth noting that this critical approach is typical of the Platonists in the second century CE who debated on the harmony between Plato and Aristotle. What we know of the early Platonic-Pythagorean reception of Aristotle’s Categories in the first century BCE (e.g. from the testimonia on Eudorus of Alexandria in Simplicius, or from Pseudo-Archytas’ treatise on categories) points instead to a different direction. At that early stage, Aristotle’s categories were probably incorporated within a Platonic-Pythagorean doctrinal framework: some of Aristotle’s views were indeed criticized or adapted, but the distinction between intelligible and sensible beings was not used against his division. Rather, Pseudo-Archytas suggests that Aristotle’s first category was initially regarded as including both sensible objects and Ideas.10 Nicostratus’ and Plotinus’ remarks about how intelligible and sensible beings can be ranked under the same genera probably reflect a later phase in the reception of Aristotle’s philosophy.
Another aspect is worth noting. We know from Simplicius (in Cat. 82.6–7; 90.31–3) that according to Alexander of Aphrodisias, Aristotle’s account of primary and individual substance in the Categories can also be applied to the separate intelligible Form; that is, the prime mover (unlike Aristotle, Alexander regards the unmoved mover as a Form separate from matter) (see Guyomarc’h 2008). Thereby Alexander possibly aimed to counter Nicostratus’ objection that Aristotle neglected intelligible beings in his account of categories.11 This fact reveals how puzzling Plotinus’ remark that Aristotle omitted ta malista onta really is: for there are obviously intelligible substances in Aristotle’s philosophy (i.e. the unmoved movers, Alexander of Aphrodisias’ separate Forms) and it would seem misleading to reject Aristotle’s account of substance on the ground that it leaves out the intelligibles. Either Plotinus (and Nicostratus before him) deliberately ignored Aristotle’s account of intelligible beings, or Plotinus and Nicostratus did not regard Aristotle’s theory of intelligible ousia as capable of answering their criticism. Whatever we might think of Nicostratus, Plotinus was certainly familiar with Aristotle’s theology but, rather surprisingly, does not mention Aristotle’s intelligible movers in his treatise On the Genera of Being. Why so? Simplicius is again helpful in solving this predicament, for at in Cat. 73.19–21 he specifies that Lucius, Nicostratus and Plotinus argued that intelligible and sensible items cannot share the same ousia, since they form an ordered series where the intelligibles are paradigms whereas the sensibles are copies. Hence these Platonic opponents of Aristotle did not merely assess Aristotle’s division of genera against the distinction between intelligible and sensible beings (which would indeed leave the question of the intelligible movers open); rather, they assessed Aristotle’s account against a precise view of intelligible and sensible beings; that is, the Platonic view of the intelligibles as models and primary beings, according to which sensible objects are merely copies of the intelligible ousiai.
This approach is obviously misleading, since Aristotle did not omit Plato’s Ideas, but rejected this theory and developed a different account of ousia. Even Alexander of Aphrodisias, who held a strongly essentialist reading of Aristotle which converges with Platonism on several issues, rejected Plato’s separate Forms.12 In Nicostratus’ and Plotinus’ criticism as reported by Simplicius, Aristotle’s views on genera and substance are ultimately assessed against a Platonic philosophical background rejected by Aristotle and his followers. Aristotle is criticized for not being a Platonist. This ideological, rather than genuinely philosophical, criticism fits well into the second-century debate on the harmony between Plato and Aristotle and recalls Atticus’ vehement anti-Aristotelian polemics.13 Whatever might be the case with Lucius, it is extremely likely that Nicostratus shared Atticus’ anti-Aristotelian approach. Certainly, Plotinus took this criticism as the starting point of his enquiry about substance and categories and incorporated Nicostratus’ puzzles into his discussion. Yet, as we shall see in the next section, this schematic Platonic criticism is not Plotinus’ last word on this issue and his discussion of Aristotle’s ousia is actually far more sophisticated.
PLOTINUS
Plotinus’ account of Aristotle’s sensible substance in Enn. VI.1[42] ends with a general critical remark: his opponents’ view does not make clear the concept and the nature of substance (ten ennoian tes ousias kai tēn physin, Enn. VI.1[42].3.22). This remark can indeed be seen as a restatement of the criticisms already raised by Nicostratus and incorporated by Plotinus in the immediately preceding chapters. For a Platonist, the real nature of primary being coincides with that of Platonic paradigmatic intelligible beings. Since Aristotle did not focus on these, he did not explain what the nature and concept of substance really are. Plotinus, however, does not stop at that and most interestingly comes to this critical conclusion after a detailed scrutiny of some questions internal to the Peripatetic theory of sensible substance. This is a crucial move and one that characterizes Plotinus’ distinctive approach. The discussion starts at Enn. VI.1[42].2.8, where Plotinus, immediately after paraphrasing the objections raised by Nicostratus, says that he will now focus on “the substances here below themselves”. First he refers to the Peripatetic distinction between matter, form and composite within ousia, and asks what can be common to these (Enn. VI.1[42].2.8–10). Then he argues that according to his opponents these are all substances, but form is said to be substance more than matter is. Plotinus agrees, but adds that others (the Stoics?) would say that matter is more substance (Enn. VI.1[42].2.12). Another puzzle is connected to the distinction between primary and secondary substances: what can be common to them, if secondary substances derive their name of “substances” from primary ones (Enn. VI.1[42].2.12–15)? Then Plotinus claims that it is impossible to explain what ousia is (ti estin he ousia, Enn. VI.1[42].2.15). Invoking the proper characteristic of “being that which is one and numerically the same which is able to receive contraries” (Aristotle, Cat. 4a10–11, trans. Ackrill, adapted) does not suffice for this purpose (Enn. VI.1[42].2.16–18). Chapter 3 of Enn. VI.1[42] begins with a further remark: one might perhaps include all divisions of ousia (intelligible ousia, matter, form and composite) within the same genus by conceiving this genus not as a common synonymous predicate, but as a hierarchical unity of provenance from a single principle. Hence intelligible ousia would be a primary one, whereas the other things (ta alla) would be ousia to a secondary and lesser degree (ab uno relation): something like the genus of the Heraclids (Enn. VI.1[42].3.1–4) (for further details, see Chiaradonna 2002: 227–71). As we shall see below, this solution was actually adopted by later commentators in order to answer Nicostratus’ and Plotinus’ objections. Plotinus, however, is sceptical, for if this were the case, everything should be included in ousia, since all beings derive from substance (Enn. VI.1[42].3.5–7). Indeed, one might reply that there are two kinds of derivation: that within the genus of substance and that of other beings from substance (Enn. VI.1[42].3.7–8). But Plotinus further remarks that this does not solve the problem, if we do not grasp what is the most essential thing (to kyriōtaton) about substance, which enables other things to derive from it (Enn. VI.1[42].3.8–10). What Plotinus provides in the following lines is a succinct scrutiny of the ways in which Aristotle and his commentators attempted to grasp the genus of substance and clarify its nature. Plotinus mentions some standard Peripatetic ways of referring to sensible substances such as being a tode ti or being a primary subject (Enn. VI.1[42].3.12–16). Very interestingly, at Enn. VI.1[42].3.16–19 Plotinus paraphrases a Peripatetic argument according to which features that are constituent “parts” of their substantial subjects (in Plotinus’ example, Aristotle’s secondary substances) are themselves substances, whereas accidents such as “white” are predicated of (and inherent in) subjects independent of them (Alexander of Aphrodisias uses this argument in order to explain why form is not inherent in body as an accident).14 The conclusion mentioned above comes after this section. Plotinus argues that one might well say that those listed by his opponents are peculiar properties of substance that only demarcate substance by comparison with other things (pros ta alla, Enn. VI.1[42].3.20). This, however, is not yet enough to define ousia as one genus, nor does it make clear the concept and nature of substance in itself (Enn. VI.1[42].3.21–2).
Here, as elsewhere, Plotinus’ discussion is developed as an internal criticism of Aristotle.15 Plotinus argues that Aristotle’s account of ousia is not only incomplete (for one should supplement Aristotle’s sensible ousia with Plato’s separate substance), but also self-refuting: while Peripatetics claim that ousia has a primary status over what depends on it, they cannot ground this priority, as they are unable to conceive of ousia adequately and in itself.16 According to Plotinus, the only satisfying way to make sense of priority is the Platonic one, which makes ousia metaphysically separate from the whole structure of sensible being. Hence the ousia of x must not be something primary and essential in sensible particulars (i.e. something in sensible particulars which makes them what they are), but must rather be an extra-physical and self-subsisting principle which acts as an essential cause for that which it is the ousia of. While the Peripatetics recognize that ousia must be prior and separate, what they actually provide is instead a mere descriptive inventory of sensible items, in which some proper features are demarcated from all others and factually referred to substance. They do not give any genuine reason for this claim and do not provide any appropriate account of substance.17 Plotinus’ final remark that his opponents cannot make of ousia a genus is best understood against the background of his distinction between genera and categories (Enn. VI.1[42].1.15–18; VI.1[42].4.51–2; VI.1[42].9.25–32; VI.1[42].10.41). Plotinus’ point is that categories are mere factual collections of items bereft of any internal unifying principle (from this perspective, Plotinus’ critique is somewhat similar to Kant’s famous remark about the rhapsodic character of Aristotle’s list). A genus, by contrast, should collect the multiple items under it in a properly unified way; but according to Plotinus only real intelligible and paradigmatic genera can ground this kind of unity (for they are both genera and principles: see Enn. VI.2[43].2.10–14). The Peripatetic list of proper features of substance does not satisfy this requirement and does not allow us to grasp what ousia is in itself. Hence, Plotinus’ criticism leads to the conclusion that in order to ground Aristotle’s ontic distinctions sufficiently, one should transgress the boundaries of Aristotle’s philosophy and endorse another view, that of Platonic intelligible beings.
Very interestingly, the previous debate within the Peripatetic tradition could suggest Plotinus’ conclusions. As noted above, two different accounts of substances are present in Aristotle’s corpus. We know from Simplicius (in Cat. 78.4–20) that Boethus of Sidon, one of the early commentators of Aristotle in the first century BCE, relied on the account of the Categories (where substance is conceived of as a primary subject) and assessed the distinction between matter, form and composite, which Aristotle presents “elsewhere”, against the background of that account. Boethus’ conclusion was very clear: whereas matter and composite satisfy the criteria for substancehood established in the Categories, form cannot do so and lies outside substance, since it is inherent “in matter”, which is a substantial subject different from form.18 Alexander of Aphrodisias’ later essentialist view of substance was at least partially developed as a response to the earlier rival Peripatetic ontology set out by Boethus (this interpretation is developed extensively in Rashed 2007). Alexander did not reject the account of substance in the Categories, but attempted to make it compatible with the ontic priority of essential form established in works such as Metaphysics and On the Soul. As noted above, Alexander emphasized that form is not in matter “as in a subject” (i.e. form is not inherent in body in the same way as an accident such as “white” inheres in its substantial subject) but is rather a constituent part of the substantial subject. Since it is a constituent part of substance, form is itself ousia. This status is shared by all sensible essential features, most notably by the specific differentia whose status Alexander (rather problematically) equates to that of form.19 Plotinus is familiar with the “parts of substance” argument (see above), but Alexander’s response would not be sufficient according to him: for claiming that some features of sensible objects have substantial priority over all others does not suffice to adequately ground this priority. The question remains open of how a selection of substantial features can be made within a Peripatetic philosophical view: for example, how we can select those qualities of sensible objects which are constituent differentiae. Plotinus’ answer would be that such selection lacks any proper ground within a Peripatetic approach, since both differentiae and accidental qualities are qualitative features of sensible objects, which share the same status and therefore cannot be sufficiently distinguished. Accordingly, Plotinus argues in Enn. VI.2[43].14.18–19 that constituent features of sensible and qualified ousia do not apply to substance “as such” (holōs).20 Furthermore, Plotinus raises the same kind of criticism against the Stoics at Enn. VI.1[42].25–30. He argues that their corporealist view makes it impossible to really distinguish God as the active principle from ousia/matter. God would in fact be nothing but “matter in a certain state” (hylē pōs echousa, Enn. VI.1[42].27.7) and the only way out of this predicament would be to regard God as an incorporeal and formal principle metaphysically distinct from matter (Enn. VI.1[42].26.10–15).
Claiming that Aristotle’s ousia cannot have any primary ontic status leaves the question open of how to grasp ousia adequately and in itself. Plotinus tackles this problem in the second part of the Genera of Being, where he focuses on genera in the intelligible world. In the first chapter, Plotinus recalls what he takes to be Plato’s view on being. He thus opposes real paradigmatic and intelligible being to what others think is being, but should instead be called “becoming” or even “not being” (Enn. VI.2[43].1.20, 24). Plotinus’ agenda is set out at Enn. VI.2[43].1.30–33: first he shall enquire on true being “on the assumption that it is not one”;21 afterwards he shall say something “about becoming and what comes to be and the universe perceived by the senses” (see Enn. VI.3[44]). True being is the perfectly unified and interconnected world of Forms, which Plotinus famously conceives of as thought-activities of the non-discursive divine Intellect. Plotinus’ programme of grasping what ousia is in itself entails, then, that we understand the nature of the intelligible paradigmatic being appropriately and without applying to it categories only appropriate for the sensible world. This is what Plotinus actually says in Enn. VI.2[43].4, where he opposes the nature of bodies and that of intelligible substance as two mutually exclusive domains. The investigation of intelligible substance and its genera entails that we remove all features that belong to bodies (Enn. VI.2[43].4.12–17).
This programme takes it for granted that we can get an adequate understanding of the essence proper to divine, intelligible being. This is the positive side of the approach negatively set out in Enn. VI.1[42].3, where Plotinus claims that Aristotle and his followers do not make clear what the nature and concept of substance really are. As Plotinus argues in Enn. VI.5[23].1–2, our soul should grasp intelligible beings through the principles appropriate to them and without making use of principles only appropriate for understanding the nature of bodies. Plotinus’ metaphysics may thus be viewed as an over-ambitious science of divine being “as such” (see Chiaradonna 2011). In fact, both bodies and intelligible beings entail multiplicity, but according to Plotinus of two radically different kinds: for bodies are made of quantitative and extensional parts which are one outside the other, whereas intelligible beings make a perfectly interpenetrated whole where parts are neither quantitative nor mutually external.22 The crucial point raised by Plotinus in Enn. VI.2[43] and Enn. VI.5[23] is that we cannot grasp the intelligible kind of multiplicity by taking the corporeal kind of multiplicity as a starting point (hence Plotinus’ infrequent use of the via analogiae in the treatises On the Genera of Being). The theory of supreme genera developed in Enn. VI.2[43] is in fact Plotinus’ most sophisticated attempt to outline how the distinctively intelligible non-discursive kind of multiplicity is structured (esp. Enn. VI.2[43].7–8 and 19–22).
One might indeed ask how we come to this science of intelligible being, since our soul’s discursive cognitive activity is ordinarily directed to “external” sensible objects (Enn. V.3[49].4.15–16), and these cannot be used as a starting point for our knowledge of intelligible substance. The answer lies in Plotinus’ view of our self: for our self is not only embodied, but is directly connected with the eternal, non-discursive and intelligible Intellect through the highest part of our soul.23 Accordingly, our soul is always acquainted with true being, although we are ordinarily not conscious of this fact. This approach emerges in Enn. VI.2[43].5–7, where Plotinus argues that we come to grasp genera in real being by focusing on the soul and how it is structured. His point is that there is a set of concepts, such as substance and life (Enn. VI.2[43].7.2), which we discover in our soul and grasp appropriately when we turn our cognitive power away from bodies. It is crucial that these concepts pertain primarily to the intelligible realm. Hence they are not predicates of the sensible world, which we apply analogically to the intelligible one; rather, they are aspects that characterize intelligible being in itself and are only derivatively (homonymously) applied to the sensible world (Enn. VI.3[44].2.2). It is by reflecting on these concepts proper to the intelligible that we “discover” the five supreme genera that, as noted by Remes (2007: 145), are “the necessary condition of Intellect’s life and act of thinking”. Therefore, Plotinus’ notion of substance in itself is toto caelo different from that which the Peripatetics refer to bodies and their constituent features. Plotinus’ substance coincides in fact with the incorporeal and non-discursive nature of the Intellect that we discover within us by removing all categories appropriate to bodies and by reflecting on how our intelligible soul is structured.
This position entails several problems and the question of how we can grasp directly and adequately the nature of divine, intelligible being is certainly a crux in Plotinus’ philosophy. Here I will not focus on this issue, but will recall another set of problems which pertain to Plotinus’ account of substance. If the nature of substance coincides with intelligible being, the status of sensible particulars becomes difficult to assess (on Plotinus’ account of sensible particulars, see Remes 2007: 35–55). As noted above, Plotinus refrains from describing sensible objects as ousiai in Enn. VI.2[43].1. Substance can neither be a body nor something “in bodies” like Aristotle’s essential and enmattered forms. But this leaves open the question of how to regard sensible particulars. If their ousia is a self-subsisting principle external to them, the conclusion can hardly be avoided that sensible particulars are in themselves mere unstructured wholes in which nothing is essential. In Enn. VI.3[44].8 Plotinus actually seems to reject the Peripatetic view that some features are constituent of bodies, for they make each body the (kind of) entity which it is, whereas other features are merely extrinsic accidents. The Peripatetic distinction between differentiae and accidents tends to vanish in Plotinus’ physical world and sensible particulars emerge as mere “conglomerations of qualities” which the causal activity of the logos (their intelligible forming principle) produces in matter (Enn. VI.3[44].8.27–37; VI.3[44].15.24–38; see Kalligas 2011). Elsewhere, however, Plotinus appears to hold a different position, since he establishes a hierarchy between constituent and accidental properties within sensible particulars and maintains that constituent features are activities that derive from the logos, whereas accidents have a different origin (which Plotinus however does not specify) (see esp. Enn. II.6[17].2.20–26). While some ingenious attempts have recently been made to reconcile Plotinus’ accounts of the status of sensible particulars, I am inclined to think that the question must remain open (see Karamanolis 2009). It is difficult to avoid the impression that Plotinus’ accounts reveal an internal tension, for either he is conceiving of sensible particulars as endowed with an internal structure, which corresponds to a hierarchical order among their properties (but this comes too close to the notion of “essential property”, and according to Plotinus sensible particulars are not endowed with essences), or he is conceiving of sensible particulars as integrally unstructured and qualitative wholes, where “completing” and “extrinsic” properties cannot be opposed (but this apparently jeopardizes an adequate explanation of sensible particulars, and Plotinus does not appear willing to abandon the idea that some properties are more “important” than others).24
PORPHYRY AND LATER NEOPLATONISTS
As noted above, Plotinus’ account of substance laid the ground for later Neoplatonic discussions. This, however, does not mean that Plotinus was unanimously followed. Certainly some crucial features of his approach were preserved: this holds for his discussion of Aristotle’s ontology against the background of Platonic metaphysics and for his in-depth first-hand reading of both Aristotle’s treatises and the previous commentators (in particular Alexander of Aphrodisias). From this perspective, Plotinus can really be seen as the founder of Neoplatonism. Plotinus’ most distinctive ideas (e.g. his internal criticism of Aristotle and the non-analogical account of intelligible ousia), however, had a difficult reception from Porphyry onward. In his extant works on the Categories, Porphyry never overtly criticizes Plotinus, but his overall programme of harmonizing Aristotle with Plato can hardly be seen as a prosecution of Plotinus’ distinctive approach.25 What emerges from Porphyry’s short commentary on the Categories, from the testimonia on his extensive lost commentary ad Gedalium in seven books and from other texts is a different overall view.26 Unlike Plotinus, Porphyry has no hesitation in incorporating Peripatetic theses within his Platonic philosophy. This was possibly part of Porphyry’s overall project of establishing a unitary Hellenic tradition of thought in opposition to the Christians. Indeed, Porphyry’s attitude was not unprecedented, and Platonists before Plotinus had already incorporated Aristotle’s views within their philosophy. While Plotinus can be seen as building on the anti-Aristotelian position of Nicostratus, Porphyry is closer to such Aristotelizing Middle Platonists as Alcinous (see Zambon 2002: 295–338). This is only part of the story, however, for Plotinus uses Nicostratus’ criticism as a starting point, but develops his discussion of Aristotle in a highly distinctive way, and Porphyry does not merely incorporate Aristotelian tenets within his philosophy, but engages in extensive commentary work on Aristotle’s treatises, drawing from previous Peripatetic commentators such as Boethus, Herminus and Alexander. Porphyry, therefore, was not merely an Aristotelizing Platonist: in addition to that, he was the first Platonic commentator of Aristotle (see Karamanolis 2004).
In his commentaries on the Categories, Porphyry follows the standard Peripatetic interpretation according to which the “object” (prothesis, skopos) of Aristotles’ treatise is not things/beings as such, but words that “signify” things (pragmata: in Cat. 58.18–20; 59.17–18).27 Plotinus is not mentioned, but Porphyry’s distinction between the enquiry carried out in the Categories and that on being and its genera certainly appears un-Plotinian, if not anti-Plotinian (in Cat. 59.30–33). Since the Categories deal with words that signify things, and not with things as such, it is inappropriate to assess Aristotle’s list as if it were a complete division of beings and their fundamental kinds. It has been argued that Porphyry aimed to separate logic from metaphysics and discussed the former as a metaphysically (or even philosophically) neutral subject.28 This is only partially true, however, since ontology is far from being absent in Porphyry’s logical works. Still, what we find in Porphyry’s works on the categories is not his fully developed Platonic ontology; rather, it is a simplified and partial ontology limited to sensible particulars and their immanent features. For Porphyry conceives of categories as words that signify things, and our language in his view refers primarily to the sensible world (in Cat. 91.7–12, 91.19–25). Not only that, but words are “messengers of things” and derive their basic mutual differences from the latter (in Cat. 58.23–9). Hence the division of categories reflects the basic ontic distinctions of (sensible) things. This isomorphism between language and sensible objects explains why beings are (at least indirectly) included in the enquiry in question. Porphyry’s discussion of ousia is part of this approach. From both his short commentary and what we know of his longer one the following picture emerges: Porphyry basically followed the Peripatetic account of sensible ousia as developed by Alexander of Aphrodisias. Significantly, Simplicius (in Cat. 78.20–24 = frag. 58 [Smith]) reports that Porphyry criticized Boethus’ equation of the immanent form with the non-substantial categories. Hence Porphyry regards both sensible particulars and their constituent features, such as specific differentiae, as substances (in Cat. 95.31–96.1). Aristotle’s view that sensible particulars are primary substances is explained by the subject matter of the Categories: for sensible particulars are the primary object of our language and are then regarded as primary substances, even if Aristotle himself elsewhere takes intelligible substances as primary (in Cat. 91.14–26).
The difference from Plotinus’ critical discussion of Aristotle’s sensible ousia could not be greater. Porphyry actually regarded Aristotle’s account of the sensible world as incomplete (since it had to be supplemented with Plato’s separate and paradigmatic principles: see Simplicius, in Ph. 10.32–5 = frag. 120 [Smith]), but not as inconsistent. In Porphyry’s view, Aristotle and his followers provide a satisfying account of sensible ousia, which can be fully incorporated within Platonism since it is the lower part of a larger metaphysical framework that includes Plato’s transcendental principles at its top.29 In this way, Aristotle’s ousia becomes part of Porphyry’s concordant Platonism. This holds for the Stoic views on substance and quality too, which Porphyry attempted to adapt and incorporate within his Aristotelian–Platonic framework (see Simplicius, in Cat. 48.11–15 = frag. 55 [Smith]). It is difficult to avoid the impression that Porphyry’s approach is philosophically less interesting than Plotinus’ critical discussion of Aristotle. Porphyry’s programme, however, is both subtle and very interesting from a historical point of view. Through his commentaries on Aristotle, Porphyry in fact established a central aspect of late antique philosophy, and his view of the harmony between Plato and Aristotle was shared (to different extents) by all subsequent Neoplatonists. The influence on posterity of Porphyry’s programme was thus immense and, rather ironically, his interpretation of Aristotle’s Categories was crucially important for Christian late antique and Medieval authors (see Erismann 2011).
Iamblichus, the second great Neoplatonic commentator, developed Porphyry’s programme in a distinctive way. Iamblichus’ commentary is lost, but a good deal of information about it is provided by Dexippus (a disciple of Iamblichus: Simplicius, in Cat. 2.25–9) and Simplicius, who rely on their predecessor.30 Simplicius (in Cat. 2.9–14 [Kalbfleisch]) says that Iamblichus followed Porphyry closely, but, unlike Porphyry, applied his “intellective theory (noera theōria)” on all levels. This expression refers to the metaphysical account of intelligible beings, which had a key position in Iamblichus’ exegesis (Dillon 1997; Taormina 1999). In addition to that, Simplicius says that Iamblichus took Aristotle’s Categories to be inspired by Archytas’ Pythagorean teaching (i.e. by Archytas’ apocryphal treatise on categories, which Iamblichus thought to be authentic).31 As far as we can judge, this attitude was different from that of Porphyry, who basically followed Peripatetic views when interpreting Aristotle. For example, Iamblichus, unlike Porphyry, interpreted Aristotle’s theory of substantial predication from the perspective of the Neoplatonic theory of derivation, thus regarding substantial predication as the logical expression of the metaphysical relation in virtue of which physical objects partake in separate ante rem forms (see Simplicius, in Cat. 52.9–18; Chiaradonna 2007b). Iamblichus pushed his reading of Aristotle along Platonic–Pythagorean lines so far that (as David/Elias, in Cat. 123.2–3 reports) he did not refrain from assuming that Aristotle was not opposed to Plato on the theory of Ideas. This was indeed an extreme interpretation and one that remained isolated: even Athenian Neoplatonists did not follow Iamblichus on this issue.32
Simplicius’ response to Nicostratus and Plotinus at in Cat. 76–7 is a good example of Iamblichus’ approach. Against Nicostratus and Plotinus’ critique, Simplicius first retorts that it is not correct to assess Aristotle’s view against the background of intelligible substances, for Aristotle did not intend to focus on the intelligibles in the Categories, and Archytas (the Pythagorean archegete of the teaching on categories) confirms this interpretation (Simplicius, in Cat. 76.19–23). This is the first part of Simplicius’ reply, but he soon provides a much more metaphysical response which aims to show that Aristotle’s view on ousia is actually perfectly compatible with the Platonic–Pythagorean teaching, for ousia is an intelligible genus/principle from which metaphysically lower ousiai derive (Simplicius, in Cat. 76.25–77.4). Simplicius (in Cat. 77.4–13) takes Aristotle’s division of ousiai in Metaph. 1069a30–b2 to confirm this view and, again, the Pythagorean Archytas is mentioned in support of Aristotle. Hence Aristotle’s account of ousia is ultimately rescued by regarding ousia as a hierarchical unity of derivation, which conforms to Platonic metaphysics (Simplicius, in Cat. 77.14–15). This is a very impressive response, but it is worth noting that Plotinus’ main objections against Aristotle remain unanswered: for example, Simplicius/Iamblichus does not explain why this hierarchical genus does not also include all other items that derive from substance. Furthermore, the main requirement set out by Plotinus – that of grasping what intelligible being is in itself – is in no way fulfilled by Iamblichus/Simplicius, who argues instead that Aristotle’s account of ousia and categories makes it analogically possible to grasp what intelligible beings are (Simplicius, in Cat. 74.22–75.9). Dexippus (in Cat. 41.25–7) claims that intelligible beings are incomprehensible to us and “ineffable” in themselves. Hence we apply the name ousia to them metaphorically, based on what is familiar to sense-perception. Plotinus’ account of ousia is thus completely reversed.
1. This translation raises some puzzles which I will not go into here: see Arpe (1941). The term ousia is probably impossible to translate adequately and all solutions are ultimately unsatisfying: see M. Frede & Patzig (1988: vol. 2, 16–17). Faute de mieux, here I will make a rather free use of “substance” and “essence”, and will often transliterate the Greek word.
2. See Kahn (1976: 333, repr. in 2009: 72). It has been suggested (with different emphases) that a distinctive notion of “existence” or “act of being” can be found among late antique philosophers (e.g. in Plotinus’ account of energeia as the hypostasis of the One at VI.8[39].20.9–15, in “Porphyry”’s view that einai is prior to on and ousia at in Prm. XII.21–35 and in the late Neoplatonic use of hyparxis). See the accounts in P. Hadot (1973, repr. in 1999: 71–88); Gerson (1994: 3–14); Corrigan (1996b). For further qualification, see Chiaradonna (2012a).
3. On Plotinus’ Genera of Being, see Wurm (1973); Strange (1987); A. C. Lloyd (1990: 85–97); Gerson (1994: 79–103); Horn (1995a); Corrigan (1996a); de Haas (2001); Chiaradonna (2002, with a status quaestionis at pp. 15–40). Two annotated translations are Isnardi Parente (1994) and Brisson (2008). There are several recent overviews of the Neoplatonic debate on the categories. See, in particular, Sorabji (2004: vol. 3, 56–127), with a very useful selection of sources, and Tuominen (2009: 202–17).
4. On Lucius and Nicostratus, see Moraux (1984: 528–63) and the collection of testimonia in Gioè (2002). The pre-Plotinian debates on the Categories are now extensively discussed in Griffin (forthcoming).
5. This ontic interpretation of Aristotle’s categories as (the highest and non-reducible) genera that are intended to account for all beings can be seen as problematic and influenced by Plato’s metaphysics. Note, however, that Aristotle regards ousia and categories as genera or “kinds” in APo. A 1.402a23–5; B 1.412a6. In his commentary on Metaph. 1003b21, Alexander of Aphrodisias describes Aristotle’s categories as “genera of being” (in Metaph. 245.34–5).
6. Simplicius, in Cat. 73.19–21: καὶ πῶς ἔσται κοινωνία τῆς αὐτῆς οὐσίας, ἐν οἷς τὸ πρότερον ἔστιν καὶ τὸ ὕστερον, καὶ τὸ μὲν παράδειγμα, τὸ δὲ εἰκών; That items forming an ordered series cannot be under the same genus is an Academic argument used by Aristotle against Plato (Aristotle, Metaph. 999a6–13; Eth. Nic. A4, 1096a17–23; Eth. Eud. A8, 1218a1). See A. C. Lloyd (1962). Here Nicostratus and Plotinus turn this argument against Aristotle.
7. Translations from Plotinus are taken from Armstrong (1966–88), with some slight changes. The Greek text is that of Henry & Schwyzer (1964–82).
8. These remarks can be compared with what Slaveva-Griffin (2009: 98–9) notes about the difficulties residing in the concept of “number” (Enn. V.5[7].4–5; VI.6[34]). On the one hand, “number” is a genus concept whose species are the substantial (intelligible and non-quantitative) and the monadic (quantitative) number. On the other hand, number is primarily substantial number, whereas monadic number imitates substantial number as its ontological paradigm.
9. Porphyry, Sent. 19 and 42. See Chiaradonna (2007a). In his reply to Nicostratus and Plotinus, Simplicius mentions the distinction between two kinds of asōmata (in Cat. 77.28–30). The distinction is actually present in some sections from the Enneads: see e.g. Enn. IV.2[4].1.33–41.
10. See “Arch.” Cat. 30.23–31.1 [Thesleff]. On this early debate, see Chiaradonna (2009a).
11. This would not be an isolated case. The recently discovered Categories commentary in the Archimedes Palimpsest (most probably, a long section from Porphyry’s ad Gedalium) shows that Alexander’s famous view on universals as accidents of definable natures was occasioned by the response to a puzzle raised by Nicostratus (Chiaradonna et al. 2013).
12. On Alexander’s approach to Plato’s Forms, see Lefebvre (2008). On Alexander’s essentialism, see Rashed (2007).
13. On Atticus’ polemics, see Moraux (1984: 564–82). Predictably enough, Atticus argued that Aristotle’s ten categories have no pertinence to Plato’s philosophy (Eusebius, PE XV.iv.19 = frag. 2 [des Places]). See J. Barnes (2003: 336 [“Additional Note [G]: Platonists and Aristotle’s ‘categories’”]).
14. See Alexander of Aphrodisias, Quaest. I.8.17.17–22; I.17.30.10–16; I.26.42.24–5; Mant. 122.4–12. Plotinus mentions the “parts of substance” argument in Enn. VI.3[44].5.10–25 too (see Chiaradonna 2008a). On this argument in Alexander, see Rashed (2007: 42–52).
15. Some interpreters are inclined to read Plotinus’ account of categories as a dialectical discussion whose aim is to incorporate (rather than reject) Aristotle’s theory: see (with different emphases) Strange (1987); Horn (1995a); de Haas (2001). According to such interpretations, Plotinus’ and Porphyry’s approaches would be basically similar. For a criticism of this view, see e.g. J. Barnes (2008).
16. Schiaparelli (2010) provides an in-depth account of Plotinus’ criticism of Aristotle’s views on form and definition in Enn. II.7[37].3 and VI.7[38].2. She argues that according to Plotinus, “the Aristotelian doctrine about real definitions is not wrong, but it is incomplete. It is likely that Plotinus wants to add that in some cases, namely when we want to explain how things are at the level of the sensible world, we cannot simply refer to something like definitions that indicate the essence” (ibid.: 488). I agree with this reading and would only suggest a different nuance. As I would put it, according to Plotinus Aristotle’s doctrine is ultimately wrong and self-refuting precisely because it is incomplete: for it is impossible to make sense of things in the sensible world if one omits their essential and intelligible causes.
17. Aristotle’s concept of natural priority in the Metaphysics has recently been interpreted as involving priority in “what is” something (A is prior to B if and only if A can be what it is independently of B being what it is, while the converse is not the case: see Peramatzis 2008). Plotinus would probably argue that we cannot establish a hierarchy of items like this within the sensible realm. His discussion of Aristotle’s soul (Enn. IV.7[2].85; IV.3[27].20–21) is revealing, for Plotinus claims that the distinction between soul and body cannot be grounded adequately, if the soul is conceived of as a hylomorphic form. The same holds with Plotinus’ discussion of Aristotle’s constituent differentia, for (a) the selection of those predicates of sensible ousiai which can count as differentiae lacks any adequate ground (Enn. VI.3[44].8.27–37, 10.12–28); and (b) these predicates could in no way qualify “substance as such” (i.e. intelligible substance: see Enn. VI.2[43].14.18–19, discussed below).
18. Simplicius’ passage is translated with a commentary in Sharples (2010: 77–8, 86–8). On Boethus’ ontology, see now Rashed (2013).
19. For a discussion, see again Rashed (2007: 53–79, 104–17 [with a commented French translation of Alexander’s texts on specific differentia preserved in Arabic]).
20. See Enn. VI.2[43].14.18–22: Νῦν δὲ λέγομεν οὐκ οὐσίας ὅλως εἶναι συμπληρωτικὰ τὰ τῆς τινὸς οὐσίας· οὐ γὰρ οὐσίας προσθήκη γίνεται τῷ ἀνθρώπῳ καθὸ ἄνθρωπος εἰς οὐσίαν· ἀλλ’ ἔστιν οὐσία ἄνωθεν, πρὶν ἐπὶ τὴν διαφορὰν ἐλθεῖν, ὥσπερ καὶ ζῷον ἤδη, πρὶν ἐπὶ τὸ λογικὸν ἥκειν. These lines are difficult and my previous account in Chiaradonna (2002: 137–42) stands in need of revision. Here Plotinus is probably suggesting that the properties of a particular (sensible and qualified) substance are not constituent of substance as such (οὐσίας ὅλως), i.e. of intelligible substance. See Lavaud (2008: 101 [“la substance considérée absolument”]) and Helmig (2006: 266 n. 30 [“die Substanz schlechthin”]), who provide the correct reading of ὅλως as going together with οὐσίας (cf. the similar expression ἡκίνησις ᾗ ὅλως κίνησις at Enn. VI.1[42].16.16–17, where Plotinus refers to motion as an actual intelligible principle of corporeal extensional and quantitative motion). However, I do not agree with other aspects of Lavaud’s interpretation and would still take τὰ τῆς τινὸς οὐσίας at Enn. VI.2[43].14.19 to refer to the properties of sensible and qualified substances (see Enn. VI.2[43].15.1–2). The remarks in Lavaud (2008: 102 n.1) do not seem persuasive to me. Instead, I agree with the reading provided by Helmig (2006: 265–6). I would argue that when Plotinus says that the properties of sensible and particular substances are not constituent of substance as such, he is not suggesting that there are other properties, different from the sensible ones, which are constituent of intelligible ousia. Rather, he is suggesting that the subject/property distinction is in itself incapable of accounting for how the perfectly unified intelligible being is structured (Enn. VI.2[43].15). From this perspective, the very distinction between constituent and accidental qualities is irrelevant, and Plotinus’ megista gene cannot in any way be seen as predicates of intelligible being (for they are neither essential nor accidental predicates). Hence motion is neither something accidental to substance nor something which contributes to its completion: rather, it is “substance itself” (Enn. VI.2[43].15.10). I would like to thank Stephen Menn for his comments on my previous interpretation of this passage.
21. The One is above being and is bereft of any kind of multiplicity (even that of intelligible genera). Plotinus distinguishes the status of the One from that of genera: see Enn. VI.2[43].10.20–23.
22. On Plotinus’ talk of the “non-quantitative” dimensions of substance, see e.g. Enn. IV.4[28].16.22, diastēma adiastaton and Enn. VI.6[34].17.24–5, aschēmatista schēmata. See on this the discussion in Slaveva-Griffin (2009: 95–103). A challenging account of Plotinus’ views on extension and bodies can now be found in De Risi (2012). The reference work for Plotinus’ theory of the non-discursive Intellect is Emilsson (2007).
23. On Plotinus’ dual theory of the self, see Remes (2007). It is controversial whether according to Plotinus our soul has a direct cognitive access to the world of intelligible Forms, independently of sense-perception. I tried to develop the interpretation set out here in Chiaradonna (2011, 2012b). For a different account, see Gerson (1994: 177–80).
24. I would now qualify what I wrote in Chiaradonna (2002), and would be more prudent in describing the radical anti-essentialism in Enn. VI.3[44].8 as Plotinus’ last word on the status of sensible objects.
25. For a different account, see the contributions mentioned above, note 15.
26. On Porphyry’s interpretation of Aristotle, see Evangeliou (1988) and Karamanolis (2006: 243–330). Porphyry’s extant short commentary on the Categories has been newly re-edited after Busse’s classical C.A.G. edition: see Bodéüs (2008). The testimonia on Porphyry’s great commentary ad Gedalium in seven books (see Simplicius, in Cat. 2.5–9) are collected in A. Smith (1993 [45T-74F]). A substantial section from this work (corresponding to the commentary on Cat. 1a20–b24) is probably preserved in the Archimedes Palimpsest: see Chiaradonna et al. (2013).
27. For an English translation of Porphyry’s commentary, see Strange (1992). On Porphyry’s semantics, see A. C. Lloyd (1990: 36–75); Van den Berg (2008); Griffin (2012).
28. This reading has been developed in different ways by Ebbesen (1990) and J. Barnes (2003). Criticism in Chiaradonna (2008b).
29. I developed this reading in Chiaradonna (2007a, 2007b).
30. Fragments in Dalsgaard Larsen (1972). The relation between Dexippus and Simplicius’ sources is intricate. P. Hadot (1974, repr. in 1999: 355–82) argued that Dexippus follows Porphyry’s ad Gedalium rather than Iamblichus, but this conclusion has been questioned by Dillon (1990: 75 n. 13) and Luna (2001: 774). Be that as it may, Dexippus did not entirely follow his master’s Pythagorizing interpretation. On Dexippus see now J. Barnes (2009). Several studies and translations have recently been devoted to Simplicius’ in Cat. Luna (2001) is fundamental.
31. See above, note 10.
32. Here I can only sketchily outline Proclus’ position. Some recent works have shown that Proclus attempted to incorporate and adapt elements of Aristotle’s hylomorphism within his own physics and metaphysics (see Opsomer 2009). However, Proclus was far from unreservedly positive in his overall assessment of Aristotle. In particular, in his commentary on the Timaeus Proclus regards Aristotle’s causal explanation of the physical world as inferior to that of Plato, on account of the fact that Aristotle confined his research to “subservient” physical causes, i.e. matter and enmattered forms, leaving out the most fundamental causes that transcend the physical world, i.e. the efficient and productive cause (the Demiurge), the paradigmatic cause (Ideas) and the final cause (the Idea of the Good) (see on this Steel 2003). Despite their very different emphases (critical vs. concordant), Proclus’ position is, from this perspective, closer to that of Porphyry than to that of Plotinus, for Proclus does not reject the view that Aristotle’s causal theory may be applied to the physical world (although it must be supplemented with Plato’s superior causes): hence, we find no trace in his writings of Plotinus’ internal criticism of Aristotle. On Proclus’ account of enmattered essential form, see esp. in Ti. II.25.6–9 [Diehl] with the discussion in Helmig (2006). On the different meanings of ousia in Proclus’ commentary on the Timaeus, see Baltzly (2007: 37 n. 3).