## 1. Historical Survey


### 1.1 Byzantine Culture and Education




One conspicuous feature of Byzantine literary culture in general, and
the study of philosophy in particular, is its relative continuity with
ancient Greek literary culture. In Byzantium, the treasures of this
culture never had to be discovered, as they were in the 9th-century
Arab East, or even rediscovered, as in the 12th-century Latin West. At
all times, Homer's *Iliad* remained the most important
textbook for secondary education. Still, this continuity is not
absolute: considerable parts of the literary heritage were pushed into
oblivion in periods of cultural decline, some of which were eventually
lost, whereas others survived to attract new attention during the
subsequent periods of intensified activity. The most important periods
of intensified activity, so far as the history of philosophy is
concerned, are: (1) the late Phrygian to early Macedonian
(842-959), when ancient philosophical texts were saved for
posterity by the production of new copies in minuscule script; (2) the
late Macedonian to early Komnenan (1042-1143); and (3) the early
Palaiologan (1259-1341). Each of these periods was ushered in by
the establishment of an Imperial School of Philosophy in
Constantinople. Apart from the Imperial Schools, private tutorial
played an important part in higher education, some teachers attaining
considerable fame, for example Nikephoros Blemmydes
(1197-c. 1269), Gregory of Cyprus (1241-1290), Nikephoros
Gregoras (1293/94-1360/61) and George Gemistos Plethon
(c. 1360-1452). In the Komnenan (1182-1204) and
Palaiologan (1259-1453) periods, the Patriarchal School loomed
large, at times existing side by side with the Imperial School, but
apparently specially designated for the education of the clergy.




There was never in Byzantium anything resembling the autonomous
universities of the Latin West. Higher education was designed to train
officials of the state and church, not masters of the arts and
sciences. The Greek-speaking world was small and decreasing, and there
was scarcely any demand in it for very specialized scholarship.
Moreover, theology never developed into the kind of systematic
discipline it became in the Latin West, and logic was never
acknowledged as an ancillary discipline (although it was taught at the
Patriarchal School, at least in the Palaiologan period). All this
contributed to the prevalence in Byzantine higher education of an
encyclopedic ideal, and to the preference of rhetorical over
philosophical studies.




There is reason to think that the task facing Leo the Mathematician,
as he was appointed to the chair of philosophy at the Magnaura School
in the mid-9th century, was to teach Aristotelian logic. In fact,
elementary Aristotelian logic and natural philosophy combined with
elementary mathematics would always form the standard philosophical
curriculum in Byzantium. Perhaps the range of courses was slightly
expanded in the late 1040s to the 1070s, when Michael Psellos and John
Italos were Consuls of the Philosophers, but the standard curriculum
was certainly back in force at the Imperial School under George
Akropolites in the 1260s and early 1270s. The logic texts usually
studied were Porphyry's *Isagoge* as well as
Aristotle's *Categories*, *De interpretatione*,
*Prior Analytics* 1.1-7 and *Sophistici elenchi*
1-7. Periodically, there seems to have been significant interest
also in the *Posterior Analytics*, since we have no fewer than
four extant Byzantine commentaries on the second book -- in
addition to the ancient paraphrase by Themistius and the commentary by
pseudo-Philoponus -- which probably were intended to supplement
Philoponus' commentary on the first book. In natural philosophy,
extracts from Aristotle's *Physics*, *De generatione
et corruptione* and *Meteorology* would be read, whereas
the mathematics course consisted mainly of Nicomachus'
*Introductio arithmetica* and the first six books of
Euclid's *Elements*. In many cases, students would replace
some or all of these texts with compendia such as the widely circulated
*Epitome logica* and *Epitome physica* by Nikephoros
Blemmydes, or the *Logic and Quadrivium* by the anonymous of
1007 ('Anonymus Heiberg')--or indeed John of
Damascus' *Dialectica*.




It deserves to be noted that before the 12th century, the whole
Byzantine output of Aristotelian commentaries dealt exclusively with
the works on logic. No doubt this reflects the needs of the
educational sector at the time. Natural philosophy in the
7th-11th centuries is only represented by elementary compendia
such as the ones by Symeon Seth (mid- to late-11th century). There is
a commentary on the
*Physics* attributed in some manuscripts (and in Benakis'
2008 edition) to Michael Psellos, but recent research has plausibly
suggested that this is really the work of the late-13th-century
scholar George Pachymeres (Golitsis 2007). If the range of subjects
covered by the Aristotelian commentaries produced in the two decades
after 1118 is much greater, this may be due to the initiative of the
princess Anna Komnene, who seems to have commissioned a number of
scholars to write commentaries on previously neglected works of
Aristotle. This was an exceptional enterprise: it would and could
hardly have been undertaken had it not been preceded by a period of
strong interest in philosophy; but it left very few traces in the
learned activities of the immediately following decades.




Obviously, there were other forums than the schools for philosophical
discourse. Photios seems to have hosted some kind of literary salon in
his home in the 850s or 860s, and similar gatherings,
so-called *theatra*, where philosophical and other essays were
read and discussed, constituted a central element in early Palaiologan
cultural life (see Gaul 2011).


### 1.2 Literary Forms of Byzantine Philosophy




Since Byzantine education was so preoccupied with rhetoric, it is
perhaps no wonder that we find a rather large diversity of literary
forms employed for philosophical purposes by Byzantine writers.
Obviously, this diversity to some extent reflects the various needs of
educational and scholarly practice. But there are many literary forms
that do not readily lend themselves to use in such contexts; these, then, will
have been cultivated for other reasons.




One such form is the dialogue. The philosophical dialogue endured
throughout the whole Byzantine era, even if perhaps it did not flourish
as abundantly as in the contemporary West. By and large, it seems
possible to divide the extant specimens into two subcategories: Plato
pastiche and Lucian pastiche. In the latter subcategory belongs the
early 12th-century satire *Timarion*, which offers some amusing
mockery of contemporary or near-contemporary philosophy professors like
Michael Psellos, John Italos, and Theodore of Smyrna. The elenctic
dialogue in Plato's style seems to have been considered
particularly useful for polemical purposes. Many dialogues in this
subcategory have a more theological than philosophical content, but
Theodore Prodromos' (c. 1100-1170) relatively good-humoured
*Xenedemus, or, Predicables*, and Nikephoros Gregoras'
(1293/94-1360/61) rather more virulent *Phlorentius, or, On
Wisdom* are two conspicuous exceptions. A particularly intriguing
example is *Hermippus, or, On Astrology*: this attempt at a
reconciliation between the belief in astral influence over the natural
world and the Christian doctrines of divine providence and human free
will is one of three anonymous dialogues, probably from the
early 14th century, which have been variously attributed to Nikephoros
Gregoras, John Aktouarios and John Katrones (or Katrarios) (Hohlweg
1995).




Philosophical treatises, vaguely defined as prose monologues on
particular themes arguing personal views, are found predominantly from
the three most philosophically productive periods (see section 1.1).
They were composed by numerous authors and for various purposes, some
of them, no doubt, strictly pedagogical or scholarly; but we will here
only mention two examples of a slightly more topical and literary
character. The philosophical essays (*Logoi*) of Nikephoros
Choumnos (c. 1250/55-1327) are written in a personal but hardly
original style--much in keeping with the views propounded in
them--which does not always correspond to the author's
professed ideal of clarity. Those of Theodore Metochites
(*Semeioseis gnomikai*, c. 1326) represent a
further move in the direction of essays in the strict and narrow sense.
Inspired by Plutarch and anticipating Montaigne, Metochites seems to
have conceived of them as adding up to a 'self-portrait as a
philosopher', theorizing about, and obviously trying to put into
practice, the proper style for philosophy.




Metochites discussed philosophy in some of his orations
(*Logoi*) and some of his hexameter poetry. Dodecasyllabic verse
was also put to use, notably by John Tzetzes (c. 1110-1180), who
wrote a 1700-line paraphrase of Porphyry's *Isagoge*. The
Byzantines are also known for having enthusiastically cultivated the
art of writing letters, in which they occasionally dealt with
philosophical questions (e.g., Michael Psellos, *Letter to
Xiphilinos*; Theodore Prodromos, *On 'Great' and
'Small'*).




Turning to those literary forms that can be assumed to have had an
educational or scholarly purpose, the kind of texts that bring us most
closely into contact with the daily reality of philosophy classes are
undoubtedly the collections of questions and answers that have been
handed down from the 1040s to 1070s, the most well-known of which is
perhaps the *Quaestiones quodlibetales* by John Italos (c.
1025-after 1082).




A very well-represented philosophical genre is the compendium. Most of
these cover only a part of philosophy, like the logic compendium by
John Chortasmenos (c. 1370-1436/37), the *Quadrivium* by
George Pachymeres (1242-c. 1310), or the *Logic and
Quadrivium* by the anonymous of 1007 ('Anonymus
Heiberg'). Some of them attempt universality, like
Pachymeres' paraphrase-compendium of Aristotle's
philosophical writings (the *Philosophia*), or indeed Joseph
Rhakendytes' (died 1330) *Encyclopedia*, which also
included rhetoric and medicine. As to the question of why the
Byzantines produced compendia, there can be little doubt that they
mainly did so for educational purposes. Most of the compendia are
wholly or partly concerned with logic, the most basic subject in the
philosophical curriculum. They do not contain detailed comments for
people already initiated in the subtleties of Aristotelian logic;
rather, they are introductory texts that do not presuppose any
significant knowledge of the subject. 




A large proportion of the Byzantine philosophical texts consist of
commentaries on ancient authorities--in fact, almost invariably
Aristotle. The only Plato commentary from the period after c. 730 is
George Pachymeres' supplement to Proclus on the last 24 pages of
the *Parmenides*. These commentaries are not, however, all made
according to the same pattern. A few main categories can be discerned,
and even within some of these categories, there is considerable
variation. The most basic type of commentary is (a) simply a
collection of scholia or notes, usually transmitted in the margin of
the Aristotelian text. The individual scholia of such a collection may
be the work of an indeterminate number of scholars. An example is
Arethas' scholia on the *Isagoge*, which draws on many
earlier commentaries, some of which are now lost. It is Arethas'
commentary in the sense that he copied, and possibly collected and
edited, the scholia in his Aristotle manuscript; in terms of
authorship, however, it is a product of mass collaboration. Next, (b)
the collection may be provided with an introduction dealing with
preliminary questions. Rules for the composition of such introductions
were established by the Alexandrian commentators on Porphyry and
Aristotle in the 5th-7th centuries. The best examples in the
period after c. 730 of collections of scholia with introductions are
probably the commentaries on Porphyry's and Aristotle's
logical works by Leo Magentenos (late 12th or early to mid-13th
century). Further, (c) the notes can be integrated in a running
commentary, so as to form a quasi-independent whole, each new section
introduced by a lemma from the text. This is the standard type of
so-called 'exegetical commentary' typified by Alexander of
Aphrodisias and cultivated in Byzantine times by Michael of Ephesus
and Eustratios of Nicaea in the early 12th century. (d) The
Alexandrian 6th-7th-century commentaries are sometimes divided
into more or less even chunks (*praxeis*), each starting with a
lemma followed by a general explanation of its meaning
(*theoria*), and then proceeding to comments on particular
points (*lexis*). While there are no clear-cut examples of this
type of commentary from Middle or Late Byzantium, its influence can be
traced, for instance, in Eustratios' commentary on *Posterior
Analytics* 2. (e) An even more advanced form is represented by
George (Gennadios) Scholarios' commentaries, which, in the
manner of contemporary Latin works, are divided into
'lessons' (*anagnoseis =* *lectiones*),
each of which is subdivided into an introduction, a broad analysis of
the text into sections, a detailed analysis with interpretations of
particular points, and finally 'investigations'
(*zetemata = quaestiones*).




The genre of Aristotelian paraphrase, that is, adaptations in which
Aristotle's text is rephrased, reorganized, and amplified or
pruned, as need be, in order to make it more easily understood, was
allegedly invented by Themistius in the mid-4th century, revived by
Michael Psellos in the mid-11th century, and further developed by
Sophonias and others in the late 13th to early 14th centuries. It is a
curious fact that the only periods from which we have dated paraphrases
of Aristotelian works are precisely these three. In addition, there is
an Arabic paraphrase that may have been based on a lost Greek
paraphrase, which must in that case have been composed in the late 6th
or 7th century (D'Ancona 2001). Works of uncertain date include
the paraphrase of the *Nicomachean Ethics* printed in
*CAG* 19 as the work of Heliodorus of Prusa (perhaps mid-14th cent.: see
section 1.3). Sophonias consciously tried to blend elements of
'exegetical commentary' with his paraphrase of the *De
anima*, in order to be able to preserve more of Aristotle's
original wording. George Pachymeres effected another kind of hybrid
paraphrase by organizing his *Philosophia* like a compendium,
which deals with a given subject, rather than a commentary or a
paraphrase, which deals with a given text.




Not only Aristotle's works were paraphrased; there are
Christianizing paraphrases of Proclus' *Three Treatises
on Providence* (the latter have since been lost in the original
Greek) by Isaac Sebastokrator (1093-after 1152) and of
Epictetus' *Encheiridion* (no fewer than three of them,
all of uncertain date; one of them, composed and provided with a
commentary no later than 960, when the oldest manuscript was copied,
seems to have enjoyed considerable popularity in the 13th and 14th
centuries: Boter 1999, 197-256). One may also note a paraphrase
of Ptolemy's *Tetrabiblos* sometimes ascribed to Proclus,
written before the end of the 10th century (Byden 2003,
352).


### 1.3 People, Works, Currents




Our brief survey of the philosophical production in Byzantium starts
in the 9th century with the work of the patriarch of Constantinople,
**Photios** (c. 810-after 893), though there is
evidence of elementary teaching of logic and ethics in the 7th and 8th
centuries, during the period of Iconoclasm. The most important
philosophical work from this period is the *Dialectica*, the
first part of **John of Damascus**' (c.
675-749) widely influential *Source of Knowledge*, which
draws mainly on the late antique commentators on Porphyry's
*Isagoge* and Aristotle's logical works. Unfortunately, the
only surviving works by **Leo the Mathematician**
(c. 790-after 869), who taught Aristotelian logic at the
Magnaura School in Constantinople, established soon after the end of
Iconoclasm, are some notes in manuscripts containing Platonic
dialogues.




But it is undoubtedly with Photios that we first encounter in
Byzantine times a large-scale revival of the study of antiquity and a
profound interest in the texts of ancient philosophers. Photios is
famous mainly for his *Bibliotheke*, a vast compilation of
ancient Greek literature, and a *Lexicon*, in which he collected
notable words and expressions. He also taught Aristotelian logic and
wrote, for this purpose, a series of small essays on Aristotle's
*Categories*, which are included in the *Amphilochia*,
an unsystematic collection of texts on theological and philosophical
topics. In these and other essays, Photios engages in a critical
discussion of some of the most central theses in ancient philosophy,
such as Plato's conception of forms, whose capacity to function
as predicates he rejects, and Aristotle's distinction between
primary and secondary substances, which he thinks entails that
'substance' is an ambiguous term.




During this "first Byzantine Renaissance", as the period
has sometimes been characterized, the archbishop of
Caesarea, **Arethas** (c. 850-932/44) also
commented on Aristotle's *Categories* and
Porphyry's *Isagoge* (cf. section 1.2). He is better
known, however, for having been instrumental in the transmission of
ancient texts, in particular the Platonic corpus. He commissioned the
transcription of a complete copy of Plato's works to which he added
marginal notes; the first part of his Plato text is extant as the
famous Clarkianus 39 manuscript in the Bodleian Library of Oxford.




In the mid-11th to early 12th centuries, there is a significant
development from the widely humanistic character of Photios' and
Arethas' interests towards a new understanding of the
philosophical enterprise. The philosopher is now regarded as someone
with a hard-earned knowledge in all branches of learning, who forms his
own views on the philosophical topics discussed by the ancients, and
moreover as someone who is interested in applying the philosophical
categories to various problems in theology or in everyday affairs.



**Michael Psellos** (1018-1078) was one of
the most erudite and intriguing figures of the Byzantine Middle Ages.
He was given the title "Consul of the Philosophers" and
taught all branches of philosophy. He commented on and paraphrased
treatises from the Aristotelian *Organon* (*De
interpretatione*, *Prior Analytics*), and wrote a large
number of short treatises discussing particular philosophical issues
raised, in part at least, by his pupils: e.g., on the distinction
between homonyms and synonyms, on the characteristic of substance as
self-existent (*authuparktos*), on the Platonic forms, on the
unity of the soul and the body, on the problem of evil, on dreams. He
also compiled the *De omnifaria
doctrina*, a short encyclopedia in which various philosophical notions are explained in close dependence on Christian as well as pagan authors. His speeches are famous as examples of rhetorical style; there is also a collection of about five hundred of his letters. Although the amount of attention he paid to Aristotle's works was significant, there is no doubt that Psellos had a strong preference for Plato and the Neoplatonists. On this account he has often -- and not unreasonably -- been identified as a pivotal figure in the transmission of the Platonic heritage through the Middle Ages. His works show that he carefully read Plotinus, Porphyry, Iamblichus, and especially Proclus, whom he considered as an authority among ancient authors. In particular, he found in the *Elements of Theology* an elaborate metaphysical system open to adaptation to Christian theology. For although the Christian Trinity differed significantly from the Neoplatonic first principle, Psellos found that Proclus' view of the general structure of reality, descending from the first cause to intellect, soul nature, body, and matter, could be adopted with some modifications. However, in his attempts to advance
philosophical learning, he was often attacked concerning his
theological orthodoxy, with the result that he often had to be careful
to distance himself from heretical doctrines, e.g., in his writings on
the *Chaldaean Oracles*.



**John Italos** (c. 1025-after 1082) was a pupil
of Michael Psellos, and his successor in the Imperial School as
"Consul of the Philosophers", where he also taught all
branches of philosophy. Anna Komnene refers to him in the
*Alexiad*, the history she wrote of the events during the reign
of her father Alexios I (1081-1118), as an exceptional thinker
and an excellent logician who interpreted Aristotle better than anyone
else in his time. Indeed, Italos occupies a special place in the
history of Byzantine thought for having been put on trial and condemned
by the Church in 1082, on the charge of having advocated the systematic
use of philosophical analysis and logical reasoning in clarifying
theological issues. Regardless of the positions he defended on such
issues, positions some of which, after all, were not at all different
from those of other philosophers, notably from Psellos', what
seems to have been really unacceptable for the religious and the
political establishment at the time was his rationalist approach
towards doctrines which the Orthodox Church considered beyond
comprehension, as something Christians should simply accept on faith
and as something only the Church had the authority to judge. It is
telling that to this day, during the mass of the first Sunday in Lent,
the so-called *Synodikon* of the Greek Orthodox Church is read,
in which Italos is anathematized in eleven articles. What mainly
survives from his writings are the commentary on the second, third and
fourth book of the *Topics*; two small treatises on dialectic
and on the Aristotelian syllogisms together with a very brief synopsis
of rhetoric; and finally, the *Quaestiones quodlibetales*, a
collection of ninety-three answers to philosophical questions posed to
him by his students, among which were the emperor Michael VII (ruled
1071-1078) and his brother Andronikos Doukas. In these texts
Italos seems to question the supremacy of theology over philosophy and
even to overturn the established hierarchy. That is to say, Italos
obviously follows the ancient conception of philosophy, well known from
both the Platonic and the Aristotelian traditions, according to which
theology is part of philosophy, since philosophy culminates in the
attempt to understand the first principle of everything. It probably
was this supposedly arrogant attempt on his part to develop a natural
or philosophical theology that led to his trial and condemnation.




After John Italos, **Theodore of Smyrna** (mid-11th
century-after 1112) was appointed "Consul of the
Philosophers". His work *Epitome of All Things Pertaining to
Nature and to Natural Principles according to the Ancients* is
still unpublished. It was conceived as an introductory compendium in
four books (three of which survive) to the topics and terminology of
Aristotle's *Physics*. 




According to a widely accepted hypothesis, **Eustratios of
Nicaea** and **Michael of Ephesus** were two of
the contributors to a series of commentaries, initiated by the
princess and historian Anna Komnene, on previously neglected
Aristotelian works. Their commentaries, in which they followed ancient
models, some of which are now lost, but also added their own
insightful remarks, were partly translated into Latin and played a
role in the development of Western Aristotelianism in the 13th
century.




Eustratios was a pupil of John Italos and became the Metropolitan of
Nicaea at the beginning of the 12th century. Anna Komnene in the
*Alexiad* presents him as an extremely erudite scholar both of
religious and of secular literature as well as a master of dialectic.
He was also asked by the emperor Alexios I to participate in various
theological debates with the Latin Church, until he himself, just like
his teacher Italos, was finally condemned for heresy in 1117. The
reasons for his condemnation are a rather complicated matter involving
both theological and political issues. In this connection, however, it
is interesting to note that he was famous for his strong conviction of
the propriety of using Aristotle's syllogistic in theology; he even
stated that Christ himself had argued with the help of Aristotelian
syllogisms. What we have of his work as a commentator are his comments
on the first and sixth book of the *Nicomachean Ethics* and his
commentary on the second book of the *Posterior Analytics*. In
interpreting Aristotle, Eustratios clearly followed the late antique
Neoplatonic philosophers, though at certain places, like the issue
concerning the knowledge of first principles, he advocated theses
which seem closer in line with his Christian beliefs. For Eustratius,
contrary to Plato and Aristotle, did not claim that the human soul
regains pieces of knowledge that we possessed at some former time, nor
that it has only potential knowledge which then becomes actual. He
believed that the human soul, when created by God, is created perfect,
that is, it has full knowledge of the principles and self-evident
common concepts, but human beings lose sight of this knowledge and
understanding, because they are susceptible to the impulses generated
by their body.




About Michael of Ephesus' life next to nothing is known. On
the other hand, it is perfectly clear that his breadth as an
Aristotelian commentator is remarkable. Indeed, Michael has been
compared to Alexander of Aphrodisias in respect both of his mode of
exposition and method of interpretation. He wrote commentaries not only
on the fifth, ninth, and tenth books of the *Nicomachean
Ethics*, but also on *Metaphysics* 6-14 and on the
*Sophistical Refutations* (both wrongly attributed to
Alexander), on the *Generation of Animals* (wrongly attributed
to Philoponus), on the *Parva naturalia*, on the *Parts of
Animals*, on the *Movement of Animals*, on the
*Progression of Animals*; furthermore, he wrote comments on the
pseudo-Aristotelian treatise *De coloribus*, and on
the *Politics*, the latter of which have only partly
survived.



**Theodore Prodromos** (c. 1100-c. 1170) continued
the tradition of writing extensive commentaries on Aristotle's works
by authoring a still unedited commentary on the second book of
Aristotle's *Posterior Analytics*, heavily influenced by
Eustratios'. A couple of his minor works are also worth
mentioning. His *Xenedemus* is a short Plato-style elenctic
dialogue on themes from Porphyry's
*Isagoge*. He also wrote a small essay, *On
'Great' and 'Small'*, which contains a
series of arguments against Aristotle's doctrine in the sixth
chapter of the *Categories* that 'great' and
'small' are not quantities but relatives, and not
contraries.




Nevertheless, not all Byzantine philosophers at the time were in
favor of harmonizing ancient wisdom with the Christian doctrines. In
fact, since Proclus seems to have represented the ancient philosopher
*par excellence*, being so much admired by Psellos and his
pupils, he understandably became the target of **Nicholas of
Methone** (early 12th century-c. 1160/66), who wrote a
detailed refutation of the *Elements of Theology*.
Nicholas' aim clearly was to provide the pious readers with the
necessary arguments against the Neoplatonic influences on Christian
dogmas, influences that on his view could lead the believers away from
the true faith. For instance, Nicholas systematically argues against
those of Proclus' propositions which try to establish that the
underlying principle of the universe is pure unity, because he
considers them contrary to the Christian belief in the Holy
Trinity.




The capture of Constantinople by the Crusaders in 1204 dealt a
severe blow to the Byzantine institutions of education and learning.
Many teachers and scholars fled the city to find a haven in Nicaea,
where the Laskarid dynasty had settled. Education and learning were
matters of great concern to the Laskarid emperors; one of them,
**Theodore II Doukas Laskaris** (ruled 1254-1258),
was himself the author of two works on natural
philosophy, *Kosmike delosis* (*Cosmic
Exposition*) and *Peri phusikes koinonias*
(*On Physical Community*), in which he brought simple
mathematical schemes to bear on elemental theory and cosmology. In
1261 Constantinople was recaptured by Michael VIII Palaiologos, and
the period of cultural prosperity that followed is sometimes referred
to as the "Palaiologan renaissance".




The most important philosophy teacher and scholar in the period
leading up to this "renaissance" was
undoubtedly **Nikephoros Blemmydes**
(1197-c. 1269). Through his students - who included Doukas
Laskaris as well as the historian George Akropolites
(1217-1282), later charged by Michael VIII with the
headmastership of the Imperial School in Constantinople - and
through his widely read compendia on logic and natural philosophy (see
sect. 1.2), Blemmydes exerted an influence that is clearly discernible
in many later philosophical works although it has never been
systematically measured. In a prefatory note to his compendium on
logic, the first version of which was apparently composed in 1237 at
the behest of Emperor John III Batatzes, he somewhat unexpectedly
emphasizes the utility of logic for theology. Indeed,
Blemmydes' services were employed on more than one occasion to
defend the Orthodox dogma of the procession of the Holy Ghost in
official debates with papal legates. The relation to the Catholic
Church was the dominating political and religious issue for most of
the 13th century. A reunion was negotiated at the Second Council of
Lyons in 1274, but it lacked popular support, and after the death of
Michael VIII in 1282, the new emperor and his patriarch pulled out of
the deal. Encounters with Dominican and Franciscan theologians may
have helped fuel the interest in logic in Byzantium during this time.
The Greek translations of Boethius' *De hypotheticis
syllogismis* and *De topicis differentiis*
by **Manuel Holobolos**, who taught logic at the
Patriarchal School between 1265 and 1273, must be seen against this
background. Other Latin philosophical and theological works were
translated by **Maximos Planoudes**
(1260-c. 1310). They do not seem to have had any discernible
impact until the mid-14th century, when Augustine's
"cogito" appears as one of several arguments against
Scepticism in a pamphlet by **Nicholas Kabasilas
Chamaetos** (c. 1322/3-after 1391); it reappears in a
similar work of unknown date, transmitted as chapter 3 of a miscellany
attributed in the (late) manuscripts to
one **Herennius**.




On the other hand, the development of Aristotelian natural
philosophy at the hands of Western masters may have encouraged their
Greek-speaking colleagues to a more intense study of the relevant
texts. As noted in section 1.2, a great number of commentaries,
paraphrases and compendia of Aristotle's works, mainly but
not exclusively on logic and natural philosophy, were produced in the
13th and early 14th centuries.




Blemmydes' compendia draw for the most part on Aristotle and
his late antique commentators, but occasionally other influences are in
evidence, such as that of John of Damascus in the *Epitome
logica* and that of the Stoic cosmologist Cleomedes in the
*Epitome physica*. Besides these two compendia, Blemmydes
composed two anthropological works, *De* *anima* and
*De corpore*, and two short treatises on a much-discussed
question of both theological and philosophical import, *Against the
Predetermination of the Terminus of Life*, in which he defends
the causal connection between moral choice and life span, although he
proceeds mostly by appeal to authority.




The historian **George Pachymeres** (1242-c.
1310), who also taught at the Patriarchal School, wrote a voluminous
Aristotelian paraphrase-compendium covering not only logic and natural
philosophy but also metaphysics and ethics, the *Philosophia*.
In addition, he wrote a textbook on the four mathematical disciplines
(the *Quadrivium*) and, more importantly,
"exegetical" commentaries on four Aristotelian works, or
groups of works, namely the *Organon*, the *Physics*,
the *Metaphysics* and the *Nicomachean Ethics*, as well
as the only Late Byzantine commentary on Plato, a continuation of
Proclus' incompletely transmitted commentary on
the *Parmenides*, which contrasts starkly with its ancient
predecessor by applying a "logical" (i.e.,
non-metaphysical) method of interpretation and a paraphrastic mode of
exposition. A growing body of evidence shows that Pachymeres was
deeply engaged in collecting, transcribing, and editing manuscripts of
philosophical authors.




Pachymeres' concern with Plato was not coincidental. If the
boom in Aristotelian studies in this period was partly a response to
the challenge of Western philosophy and theology, it seems reasonable
to think that a similar cause may be found for the rising popularity of
Plato, who was much less known than Aristotle in the West. Ever since
Late Antiquity Aristotelian logic and natural philosophy had been
commonly regarded as propaedeutic to Platonic metaphysics, and the
hierarchical relation between the two philosophers was now increasingly
stressed, sometimes (as in Nikephoros Gregoras'
*Phlorentius*) in the context of open criticism of the
Aristotelian inclinations of Latin philosophy. Platonic metaphysics
was, however, a theologically precarious field, and it is hardly
surprising if those who plowed it were not at all times equally
outspoken about the fruits of their labor. Still, in the 1260s, George
Akropolites willingly admitted that his interpretations of Church
Fathers were informed by the divinely inspired Plato, Proclus,
Iamblichus and Plotinus; and towards the end of our period George
Gemistos Plethon went so far as completely to discard Christianity in
favor of Neoplatonic polytheism.




Another early Palaiologan compendium extends its ambit to cover
rhetoric and medicine as well as the whole of philosophy. This is
the *Encyclopedia* of **Joseph Rhakendytes**
(aka Joseph the Philosopher, died 1330). Joseph drew heavily on the
works of his Byzantine predecessors. His part on logic reproduces
Blemmydes' *Epitome logica* with some additions; his part
on natural philosophy combines works by Blemmydes with works by
Pachymeres and Michael of Ephesus; his part on the quadrivial
disciplines is identical with the *Logic and Quadrivium* by
the anonymous of 1007.




A contemporary of Pachymeres was **Sophonias**, a
Constantinopolitan monk and later Catholic convert, whose hybrid
paraphrase of Aristotle's *De anima* was mentioned in
section 1.2. On stylistic grounds the anonymously transmitted
paraphrases of the *Categories*, the *Prior
Analytics*, the *Sophistici elenchi*, and the *Parva
naturalia* edited in *CAG* 23 and 5 may also be attributed
to Sophonias. Even though these works are in themselves of limited
philosophical interest, it has been shown that Sophonias draws on John
Philoponus' lost commentary on book 3 of the *De
anima* (Van Riet 1965).




Of more interest is the mostly anonymously transmitted paraphrase of
the *Nicomachean Ethics* edited in *CAG* 19 as the work
of **Heliodorus of Prusa.** This attribution is clearly a
hoax; in fact the only thing we know about the circumstances under
which the work was composed is that it must have been before 1366,
when the earliest manuscript is dated, and after the composition of
Eustratios' commentary, on which it draws. It has recently been
argued (by Trizio 2011) that it originated in the milieu around the
former emperor John Kantakouzenos (abdicated 1354).




Not all Late Byzantine philosophical authors were content to write
compendia, paraphrases, and commentaries on the classical authors. One
who decided to write essays on natural philosophy in order to
investigate the relevant questions independently of Aristotle and
Plato was **Nikephoros Choumnos**
(c. 1250/55-1327), a leading figure at the court of
Andronikos II in the 1290s and 1300s. Choumnos' main concern was
with elemental theory, cosmology, and psychology. Many of his essays
seem to have been composed on the occasion of literary gatherings
(*theatra*), some of which were presided over by the
emperor.




It is typical of Choumnos' approach that he seeks to argue
philosophically, that is by valid inference from principles and
definitions that are universally accepted, for views that are already
theologically established. Thus he attempts to refute
Aristotle's theory that the heavens are composed of a fifth,
naturally ungenerable and imperishable body, not by simply appealing
to the Christian doctrine that the world was created at the beginning
of time and persists only through the grace of its creator, but by
pointing out that Aristotle's attempt to deduce his theory from the
fact that the heavens have a circular movement fails, inasmuch as he
has only secured the premise that all simple bodies have simple
movements, not that all simple movements belong to simple bodies,
which is what his argument requires. Likewise, Choumnos argues by
elimination against the theory of pre-existing matter (which is how
he, following Aristotle, interprets the *chora* of
Plato's *Timaeus*), and insists against the theory of
separate forms that if forms do not allow self-predication, they are
not participated in by individuals; but if they do, they are not
universal and eternal, but individual and perishable. The bottom line
is that matter and form are inseparable and simultaneously
created. Another time he attacks the theory of recollection, which he
takes to entail the pre-existence of the soul, by flatly denying that
knowledge can suffer destruction or, obviously, be revived, and
stressing the fact that this follows from Plotinus' (whom he
considers to be his main opponent) view that the activities of the
soul are immortal. He even prides himself on having proved the
doctrine of the resurrection of the body on the basis of Plato's
views on the migration of souls.




Originality of thought and expression was also striven for by
Choumnos' rival and adversary at court, **Theodore
Metochites** (1270-1332). It is perhaps most clearly
attained in his *Semeioseis gnomikai*
(*Sententious Notes*), a collection of 120 essays on subjects as
diverse as the reasons for Aristotle's obscurity and for
Plato's use of the dialogue form, the interrelations between
different faculties of soul, and the pros and cons of different
political constitutions. A significant part of the essays are taken up
by meditations on the transience of human life, not
infrequently bearing on the vicissitudes of Metochites' own
life and career. He also lingered over many of these themes in his
orations, notably *On Education*.




In a more traditional vein, Metochites wrote paraphrases of all of
Aristotle's writings on natural philosophy; his proudest
accomplishment, however, was his monumental *Introduction* to
the study of Ptolemaic astronomy. The superiority of mathematics
(including astronomy) to natural philosophy is in Metochites'
view warranted by the higher degree of reality of mathematical objects,
which he seems (especially in his hexameter poem *On
Mathematics*) to have conceived of as being ultimately derived by
procession from intelligible objects, even if he sometimes speaks of
them as the products of abstraction from sensibles. The two conceptions
are probably intended to be complementary, as indeed they are in many
Neoplatonic writers.




Metochites' student and intellectual heir, **Nikephoros
Gregoras** (1293/94-1360/61), began his career as an
astronomer and ended it as a theological controversialist. Some of his
letters and a few passages of his *Roman History* touch upon
philosophical subjects: especially noteworthy is the vehement criticism
of Aristotle in the dialogue *Phlorentius*, ostensibly an
account of the author's debate with **Barlaam of
Calabria** (c. 1290-1348) in 1331-1332. As Gregoras
notes with disdain, Barlaam was well-versed in contemporary Latin
scholasticism; but it was his knowledge in ancient Greek philosophy and
mathematics (including astronomy) that aroused both admiration and
hostility when he arrived at Constantinople in the 1320s. In his
*Solutions* for George Lapithes he is largely concerned with
defending Aristotle against accusations of inconsistency with Plato as
well as with himself. In so doing he addresses issues of more profound
importance than Gregoras does in his *Solutions* for Helena
Palaiologina, which deal principally with problems of natural
philosophy; but the Neoplatonic epistemology in Barlaam's
*Solution* 4 and especially his *First Greek Letter*,
according to which scientific knowledge rests on innate
"substantial principles" in our souls, which reflect the
creative principles in the Divine Intellect, and thus indicate the
true causes of the nature of things, is curiously inconsistent with
the theory expounded in his *Anti-Latin Treatises*, which
states that the universal principles in our souls, on which
demonstrative arguments are based, are completely derived from the
experience of particulars.




Barlaam and Gregoras were both on the losing side in the Hesychast
strife, which raged between c. 1337 and 1351 and revolved around the
question of theological method. The winner was **Gregory
Palamas** (1296-1359), famous for his claim that even
though God's substance (*ousia*) is necessarily concealed
to us, we can have direct experience of his activities
(*energeiai*). The first 29 of Palamas' *150
Chapters* attempt to put natural philosophy on a more secure
footing by placing facts about the world as a whole--in contrast
to particular facts, such as astronomical phenomena--in the same
epistemological category as facts about God and Man, which are only
knowable through the teaching of the spirit. Thus Palamas expends
considerable energy on denouncing the erroneous views of the Greek
natural philosophers, Platonists as well as Aristotelians.




In the last years of the Byzantine Empire, philosophical writers
tended indeed to identify themselves as either Platonists or
Aristotelians, and to emphasize the disagreements existing between the
two ancient authorities. This approach was very different from the
harmonizing endeavors of the late antique commentators, and it was left
as a legacy to Renaissance and early modern Aristotelianism and
Platonism. Its roots are to be found in the anti-Aristotelian
sentiments of 14th-century authors such as Metochites and Gregoras, but
it came into full blossom in the great controversy which started in
1439, when **George Gemistos Plethon** (c.
1360-1452) published his pamphlet *De differentiis*, and
ground to a halt after the Latin version of Cardinal
**Bessarion's** (1403-1472) *In
calumniatorem Platonis* was printed thirty years later.




Plethon's pamphlet purported to show how inferior Aristotle was
to Plato, in spite of being more admired especially in the Latin
West. Like Metochites before him, Plethon seems to have drawn on the
Middle Platonist Atticus for his criticisms, which cover every part of
Aristotle's philosophy and end with a refutation of
Aristotle's objections to the Theory of Forms. Aristotle was
duly assisted by **George (Gennadios) Scholarios** (c.
1405-after 1472), whose *Contra Plethonem* bears
testimony to a philosophical education that was clearly more Latin
than Greek. Of paramount concern to Gennadios was the repudiation of
Plethon's claim that Aristotle's God is not creator of the
world. This is achieved *inter alia* by recourse to the
time-honored hypothesis of eternal creation. As his sobriquet
suggests, Gennadios was an extremely erudite man, who prided himself
on being a better Aristotelian commentator than his Byzantine
forerunners precisely on account of his vast knowledge of the Latin
literature, including translations of Avicenna and Averroes. His
commentaries on Porphyry's *Isagoge* and
Aristotle's *Categories* and *De interpretatione*
are the most extensive Byzantine ones on these works, and owe a great
deal, with respect to their content and form, to earlier and
contemporary works in Latin. Especially strong is the influence of
Thomas Aquinas, many of whose works Gennadios also translated, thus
continuing the efforts of
**Demetrios** (c. 1323/26-c. 1397/98) and
**Prochoros** (c. 1333/34-c. 1370/71)
**Kydones** in the preceding century.




The controversy dragged on with new contributions on Plato's
behalf by Plethon and **Michael Apostoles**; and on
Aristotle's by **Theodore of Gaza, Andronikos
Kallistos**, and **George of Trebizond**. All
these men were native Greek speakers; and except for Trebizond, they
all wrote in their mother tongue. The importance of the controversy
for Renaissance philosophy is largely due to Bessarion, who tried, in
the work already mentioned, to give a fair hearing to both
philosophers (thus reverting to the traditional approach of
harmonization), and whose systematic account of Platonism was
unprecedented in the Latin literature.




A few years after his appointment as patriarch in 1454 (thus after the
fall of Constantinople), Scholarios gave orders for all existing
copies of Plethon's *Book of Laws* to be destroyed. It is clear
from the remaining fragments that this work constituted Plethon's
prescription for a happy life for humankind, advocating an ethics and
a politics inspired by Plato himself as well as by Middle Platonic,
Neoplatonic, and Stoic writers, and propagating a philosophically
refined form of the old Olympian religion. It has been claimed (by
Tambrun 2007 and Siniossoglou 2011) that Plethon rejected the
transcendence of the highest god (Zeus), and that his theology
therefore, in contrast to both the Christian and the Neoplatonic
consensus, was entirely positive, but this appears dubious (see
Hladky 2014). One surviving chapter of the *Book of
Laws* (*De fato*) argues, both from the nature of causation
and from the assumption that the gods have foreknowledge, that all
events are determined by fate. According to Plethon, this is
compatible with freedom, not in the sense that human beings are not
ruled by anything, but in the sense that they are ruled by their own
intellect: being free is simply submitting to the decree of Zeus.
Divine punishment is justified as a method for teaching human beings
to become free. A combination of Platonic and Stoic influences is also
manifest in another short treatise by Plethon, *On
Virtues*.


## 2. Topics


### 2.1 The Immortality of the Soul




The question of the immortality of the soul is a potential point of
conflict between Orthodox Christian doctrine and Byzantine natural
philosophy. Byzantine natural philosophy, like its late antique
predecessor, was largely based on the works of Aristotle. In Book 2 of
the *De anima*, Aristotle defines the soul as "the first
actuality of a natural body which potentially has life." He
himself draws the conclusion that the soul must be inseparable from the
body. It seems clear, too, that on this view the soul cannot survive
the moment of the body's death. Still, Aristotle leaves open the
possibility that there may be some part of the soul that is not the
actuality of a body, and therefore may be separable. As he explains in
Book 3 of the *De anima*, the mental faculty by which we think
and form beliefs, *nous*, variously translated as
"mind" or "intellect", in fact lacks a bodily
organ. In one of the most intriguing and hotly debated passages of
ancient philosophy, *De anima* Book 3, chapter 5, Aristotle
introduces the notion of a kind of intellect that he describes as
productive and active, and this kind of intellect, according to him, is
not only separable from the body but is "alone immortal and
eternal." The question, then, is whether the eternal life of this
productive and active intellect is enough to ensure survival after
death for the individual human soul.




Aristotle's definition of the soul presented a formidable
challenge to Byzantine Christians and late antique pagan philosophers
alike. As Theodore Metochites explained in his *Semeioseis
gnomikai* (3.6-7),



> 
> 
> those who have commented upon Aristotle's writings are even
> unable to conclude from them whether the man thinks that the soul is
> immortal or not. Some of them are of the opinion that he does not allow
> any possibility for the soul to exist without the body, and they easily
> convince the multitude that this is so. They refer to those texts in
> which Aristotle defines the soul as dependent on the body, ruling that
> it is "the actuality of an organic body by nature endowed with
> life," without distinguishing any unique and incorporeal part of
> it, and consequently also thinking that it is destined to pass away
> with the body. Others have the opposite view.
> 
> 




Among the ancient authors who held the view that Aristotle denied
any kind of immortality for the individual human soul we find Alexander
of Aphrodisias, who famously identified the productive intellect of
*De anima* 3.5 with the first mover. Christian authors such as
Hippolytus of Rome, Tatian, Ps.-Justin Martyr, Gregory of Nyssa, and
Theodoret also claimed that Aristotle believed the soul to be wholly
mortal, and they all condemned him for it. Perhaps it is not so
surprising that the fiercely anti-Aristotelian 2nd-century Platonist
Atticus did the same; but Aristotle's definition was also
criticized by Plotinus and Porphyry, since it seemed to suggest that
the soul was not a separable substance.




One may presume that Metochites' attribution of this view to
"the multitude" expresses contempt. In fact he seems to
have sided with "the opposite view", namely,



> 
> 
> that [Aristotle] does in fact define soul as immortal and assign to
> it a unique and incorporeal mode of being. [Those who hold this view] refer
> to those texts in which he considers intellect as functioning
> separately and possessing an activity which does not require the body;
> and [they say that] both in the *De anima* and especially in
> *Physics* 7-8 he compares the intellect in the body to the
> pilot of a ship: on the one hand it governs the body, but on the other
> it is carried along with it, although it still has a separate being and
> is destined to abandon the body but not itself.
> 
> 




This was the standard view. Among those who maintained that
Aristotle did assign immortality to at least some part of the
individual soul are all the late antique commentators whose
commentaries on the *De anima* are extant.




Of the Neoplatonists, John Philoponus, whose commentary was highly
influential throughout the Greek Middle Ages though virtually unknown
in the Latin West, held that Aristotle agreed with Plato that of the
three kinds of soul (1) the vegetative soul alone is wholly
inseparable from the body; (2) the irrational soul (comprising the
faculties of imagination and sense-perception as well as appetite and
desire) is separable from the gross body, though inseparable from
the *pneuma*, and thus mortal; and (3) the rational soul, the
substance of which transcends all body, but some of whose activities
are bound up with the human body (as those of the pilot are bound up
with the ship), is wholly separable and thus immortal. It seems clear
that "rational soul" in this context is synonymous with
"intellect" in the Aristotelian texts. Ps.-Simplicius (=
?Priscian) takes a similar view, but in Ps.-Philoponus' (=
?Stephanus') commentary, the scheme is altered so as to allow
immortality even to the two perishable kinds of soul ("for they
perish not in their capacity of soul but in their capacity of being in
a body"). Thus Plato's dictum that "all soul is
immortal" (*Phdr*. 245c6) according to Ps.-Philoponus
holds true, even though intellect is the only part of soul which is
immortal *and eternal*, as Aristotle says. The interpretation
of *Phaedrus* 245c6 as referring to "both rational,
irrational and vegetative" soul is ascribed to Numenius (f. 47)
and repudiated by Philoponus (*In DA* 9.35-10.1). What
all the Neoplatonic commentators took for granted is that the
productive intellect introduced in *De anima* 3.5 is part of
the individual human soul. This must be so, since in their view
the *De anima* is a treatise on the human soul.




The interpretative tradition of the Neoplatonic commentators
stretches well beyond the 11th century, when John Italos defended what
he took to be Aristotle's position, namely that rational
soul alone is immortal, against Ps.-Philoponus' interpretation of
the above-mentioned Platonic dictum (*quaestiones* nos. 36;
50). This is also what Sophonias argued at the turn of the
14th century in his paraphrase of *De anima* 3.2. Thus both he
and Italos conformed to the same scheme as Philoponus and
Ps.-Simplicius. In the same vein, Nikephoros Blemmydes, in his *De
anima* (c. 1263), made extensive use of the analogy of the pilot of
a ship as interpreted by the Neoplatonists. First he used
it to show that Aristotle thought the rational soul was separable and
immortal; then he developed it into an image of the turmoil experienced
by the rational soul as long as it is connected with the body. And in
the early 12th century, Michael of Ephesus pointed out, when commenting
on Aristotle's dictum that the activity of the better part of us
is more serious, that the intellect which is part of us comes into its
own only after being separated from the body, which shows, he says,
"that those who claim that Aristotle was of the opinion that the
soul is mortal were fundamentally wrong" (*In NE* 10,
576.25-33).




Having thus briefly summarized the arguments both of those who claim
that Aristotle did not believe in the immortality of the soul and of
those who maintain that he did, Metochites adds an observation of his
own in support of the latter's view:



> 
> 
> And the fact is that he himself says the same thing as them in these
> very books, where he shows (following Plato, although he tries to
> conceal this) that there is one part of the self-moved thing that can
> only be moved but not cause movement, and another part which can only
> cause movement but not *per se* be moved, although it can be
> moved *per accidens* (namely, when it is moved along with the
> thing that it itself moves). From this it will follow, then, that what
> is moved by something else will also cease to be so; whereas what moves
> itself will consequently not cease to do so, and will not abandon
> itself (its essence being exactly to move itself); since it can under
> no circumstances abandon itself, it is also clear that it is part of
> its essence to exist forever and not cease from its movement, i.e. from
> its very essence and life.
> 
> 




In this passage Metochites seems to contend that Aristotle's
argument against self-movement in *Physics* 7.1 and 8.5 entails
the proposition that "what moves itself will not cease to do
so," which is used as one of the premises of an argument for the
immortality of the soul. This latter argument is apparently strongly
inspired by the first part of the proof of immortality in
Socrates' palinode in Plato's *Phaedrus*
(245c5-8). It seems to be an "ontological" kind of
argument. That is to say, it attempts to show that the (eternal)
existence of the soul follows from its nature. The soul's nature
is defined precisely as its movement, whereby it moves itself. The idea
is obviously that since the mover and the moved thing, if they are
identical, cannot be disconnected, there will always be sufficient
reason that the moved thing is moved (because there will always be a
mover connected with it) and that the mover causes movement (because
there will always be something there for it to move). Now, what seems
to be the other premise of this argument, namely the proposition that
the soul moves itself, is refuted by Aristotle in *De anima*
1.3-4 on the strength of the very proposition established in
*Physics* 7.1 and 8.5 and cited by Metochites in the preceding
paragraph, namely that movement is necessarily an irreflexive relation.
The question is, then: what reason, if any, can Metochites have for
thinking that the proposition that self-movement is eternal follows
from (an argument containing) the proposition that self-movement does
not exist?




It may be noted that Metochites deduces this proposition in two
steps. First he says that it follows from Aristotle's
view--namely, (A) that movement is an asymmetrical relation
between two contiguous entities, one of which causes movement and one
of which is moved--(1) that for any movement, if the moving and
the moved parts are disconnected, the movement will cease. Then he adds
the further inference (2) that if the moving and the moved parts are
identical, the moving part will not cease to cause movement. Since (2)
clearly does not follow either from (A) or from (1), but does seem to
follow from the converse of (1)--that for any movement,
*only* if the moving and the moved parts are disconnected, the
movement will cease--one may wonder whether Metochites may have
fallen prey to the *fallacia consequentis*: if (if *p*
then *q*) then (if not-*p* then not-*q*).




Even if we cannot definitively clear him of this charge, we may be
able to point to extenuating circumstances. The Neoplatonic
commentators, too, espouse the ontological argument for the immortality
of the soul. They also accept Aristotle's analysis of movement as
necessarily an irreflexive relation; they believe, however, that
"movement" in this context refers exclusively to physical
movement, and thus that the analysis does not concern the self-movement
of the soul. That is to say, they affirm the compatibility of the
premises of the ontological argument with Aristotle's analysis of
movement. They do not try to deduce the former from the latter. That is
why it is interesting to find in Proclus' *Elements of
Theology* (14, 16.15-23) an attempt to deduce the existence
of a self-moved soul a la Plato from that of an unmoved
intellect a la Aristotle. It is not clear that it is a
successful attempt; but it may still have predisposed some of
Proclus' readers to understand Aristotle's cosmological
argument in *Physics* 8.5 as a proof of the existence of both an
unmoved mover and (by implication) a self-moved soul. At any rate, if
this is how Metochites understood it, his suggestion that the premises
of the ontological argument for the immortality of the soul are implied
by Aristotle's analysis of movement may seem less
far-fetched.


### 2.2 Metaphysics: Universals




There is plenty of textual evidence that the attempt of Neoplatonist
commentators of Late Antiquity to reconcile the doctrines of Plato and
Aristotle on the issue of universals was closely followed in Byzantium
by prominent thinkers like John Italos, Eustratios of Nicaea,
Nikephoros Blemmydes, Nikephoros Choumnos and George (Gennadios)
Scholarios. More specifically, Byzantine philosophers as a rule adopted
the Neoplatonist commentators' three ways of understanding genera
(and species) terms as referring to:


1. the genera before the particulars (*pro ton pollon*),
which are generally identified with the Platonic Ideas in God's
mind;
2. the genera in the particulars (*en tois pollois*), which
are supposed to correspond to Aristotle's immanent forms;
and
3. the genera after the particulars (*epi tois pollois / meta tous
pollous*), which are concepts in human minds.




These three types of genera are the ones first introduced by the
5th-century Neoplatonist Ammonius in his commentary on Porphyry's
*Isagoge*; they are also discussed in Elias' and
David's commentaries on the same work, in Olympiodorus'
*Prolegomena*, and in Philoponus' commentary on
Aristotle's *Categories*. And it is the same three ways of
understanding genera (and species) terms that are discussed by Arethas
in his commentary on Porphyry's *Isagoge*, but are also
hinted at in Photios' treatise *Various Questions for
Discussion on Genera and Species* (= *Amphil*. 77) as well
as in Psellos' paraphrase of Aristotle's *De
interpretatione*.




This attempt to bring together the three ways of understanding
genera (and species) terms has been labeled as "conceptual"
or "moderate realism" (Benakis 1982), but it has also been
presented as a nominalist or conceptualist position (Joannou 1954;
Lloyd 1990). In view of this disagreement, it may be interesting to
take a closer look at the position the Byzantines advocated and to
compare it with that propounded by the Neoplatonist commentators. In
particular, it is important to focus on John Italos' views on
genera, since he repeatedly discusses them at great length in his
*Quaestiones quodlibetales* and there seems to be no earlier
indications of any more vivid or systematic interest in this issue.




In *quaestio* 5, for instance, Italos talks about the same
three types of genera in the same order, but a certain detail of his
account proves to be quite intriguing. Italos, too, regards the genera
before the particulars as the causes and paradigms of perceptible
individuals, which are not predicates, are separate from them, and
exist in God's mind, perfectly accommodating in this way the
requirements of Christian dogma. But then he presents the genera in the
particulars and the genera after the particulars in a manner which
seems to differ from Ammonius' account, for he seems to treat
them as two subdivisions of one class of genera, which is distinguished
from the genera before the particulars by being later-born
(*hysterogene*) than the perceptible individuals, capable
of being predicated of them, inseparable from them, and acquired by our
mind by abstraction. What makes the genera in the particulars differ
from the genera after the particulars, according to Italos, is the fact
that they are inseparable from the particulars in which they are: they
are not predicated of many particulars, but only of the one particular
which participates in them. The animal in Socrates is not the same as
the animal in Plato. On the other hand, the genera after the
particulars are predicated of many particulars, and it is one and the
same genus that is predicated both of all the particulars together and
of every single one of them separately.




Does this mean that Italos understands the genera in the particulars
as referring to forms which are particular? In other words, does this
mean that he interprets Aristotle's immanent forms as particular
rather than universal? The pedigree of such an interpretation is not
negligible; both Proclus in his *Elements of Theology* as well
as his teacher Syrianus in his commentary on Aristotle's
*Metaphysics* viewed the immanent forms as particulars, without
implying in any way that on this point they disagreed with Aristotle.
And although Ammonius is not clear on this subject, there is no reason
to believe that he was not here in agreement with these other
Neoplatonists. This, of course, does not mean that such an
interpretation of Aristotle's theory has to be the right one. But
it is reasonable to think that, by Italos' time, treating
Aristotle's immanent forms as particulars was an acceptable, if
not the standard, interpretation.




Most importantly, though, the point on which Italos seems to differ
from Ammonius' account of the three types of genera is that he
considers not only the genera after the particulars as acquired by our
mind by abstraction but also the genera in the particulars as such. For
it seems that the genera after the particulars are acquired by our mind
by abstraction of the common characteristics of perceptible
individuals, just like in Ammonius' commentary, while the genera
in the particulars are acquired by our mind by abstraction of the
particular form from the matter involved in each particular. Therefore,
the genera in the particulars do seem to represent, on Italos'
view, what they represent for Proclus and Syrianus, namely immanent
forms that are particular.




But if both the genera after the particulars and the genera in the
particulars are acquired by our mind by abstraction, does this mean
that, for Italos, they are not beings? On the contrary, Italos offers a
whole series of arguments to support the thesis that the genera are
beings (*quaestiones* 3, 19, 31). For this purpose he draws what
he takes to be Aristotle's distinction between two senses of
something's being incorporeal (*quaestio* 8):


1. Something is incorporeal *per se*, truly, and strictly speaking,
when it does not need a body for subsisting.
2. Something is incorporeal *per accidens* and by abstraction, when
it depends on a body for subsisting.




Thus, according to Italos' interpretation of Aristotle, the
genera are incorporeal in a weak sense, since they are not strictly
speaking incorporeal but depend on a body for subsisting. Indeed, this
is the sense that Italos himself adopts in his understanding of the
genera as incorporeal; genera are incorporeal *per accidens* and
not *per se*, because they are incorporeal insofar as they are
in the human soul, while at the same time they are corporeal by
participation (*kata methexin*) insofar as they subsist in the
particulars. And the genera that he has in mind in such contexts are
obviously the genera in the particulars and the genera after the
particulars.




But if the genera are incorporeal beings, is there a special sense
in which they are said to be beings? Italos often makes use of another
distinction, which is a commonplace in Platonic texts from Plotinus to
Simplicius, but seems to have its origins even earlier; namely, the
distinction between something subsisting and something depending on
mere thought. According to Italos (*quaestio* 19), things that
do not subsist (*anupostata*) but depend on mere thought are not
beings. As for things that subsist, he distinguishes between two
different kinds of beings; namely, between beings that subsist *per
se*, which he calls subsistences (*hupostaseis*), and beings
that subsist in something else (*enupostata*). Subsistences are
prior by perception, they are particulars and are for the most part
bodies, whereas beings that subsist in something else are prior by
knowledge, they are incorporeal, they are predicates shared by many
things, and they are thoughts (*noemata* /
*dianoemata*). Italos' terminology here clearly shows
the influence of the Christian Fathers, and in particular of John of
Damascus, who in his *Dialectica* draws just this distinction
between subsistences, things that subsist in something else, and things
that do not subsist. According to Italos, therefore, both subsistences
and beings that subsist in something else are beings, and thus do not
depend on mere thought. Italos distinguishes these two kinds of beings
from the standard examples of things that do not subsist, i.e.,
goat-stags and centaurs, as well as from his own examples of many-eyed
men and four-headed horses; for all these are, on his view, nothing but
fabrications of the human mind and products of our imagination
(*phantasmata*). On the other hand, it also is important not to
overlook the difference between subsistences and beings that subsist in
something else. Although the first subsist *per se*, the latter
are thoughts that subsist in something else.




Hence, Italos' position on the three types of genera could be
summarized as follows: All types of genera are incorporeal beings, the
genera before the particulars are subsistences whereas the genera in
the particulars as well as the genera after the particulars are beings
that subsist in something else. That is to say, although only God,
God's thoughts, and the perceptible individuals exist in the
strong sense as subsistences, all types of genera are beings; they may
be beings in a different sense, but they all are beings and not
constructions of our mind devoid of reality. For this reason, it would
perhaps be misleading to label Italos as a "nominalist",
since he does not defend the view that the *in rebus* and
*post res* genera are mere expressions, but it would also be
misleading to label him as a "realist", since he does not
think that the *in rebus* and *post res* genera are
subsistences. Presumably, it is this difficulty of pinning down
Italos' position that has led to the introduction of intermediate
labels such as "conceptualist" and "conceptual"
or "moderate realist".