Thought

Apart from the preservation of the ancient texts, Arethas deals with various philosophical issues (metaphysics, anthropology). He is usually viewed as a Platonizing thinker, mainly because of the considerable editing and his extensive scholia on the Platonic dialogues (Westerink and Laourdas 1962; Brumbaugh 1961). The proof of his scholarly concern for Plato’s texts are the marginal notes to Plato’s works (Oxon. Bodl. Clarke ms.39). He has a certain ambivalence toward Plato, expressing sometimes criticism (Charmides 155D) and sometimes positive appreciation (Phaedo 114C). It is not sure whether he wrote a systematic explanation of Plato’s treatises or whether these are only personal notes to certain issues or subject notes made in connection with sources that were available at that moment.

From the philosophical point of view, Arethas revived interest in Aristotle in Byzantine thought (Oehler 1964). He is the author of detailed comments on the first five chapters of Aristotle’s Categories (up to 4b15) and on Porphyry’s Isagoge (entire text). Arethas’ text demonstrates dependence on earlier commentaries, though it became a supplement to the extant Neoplatonic commentaries (Kotzia-Panteli 1996). He wrote marginal notes in his text, which is the oldest surviving manuscript of Porphyry’s Isagoge (Vatic. Urb. 35). He opposes Porphyry’s critics and praises his clarity. Commenting on Porphyry, he identifies universals with genera and species, supposing that every difference, property, and accident is also a genus or a species (wisdom is an accident of Socrates but it is also a species of virtue). The commentary on the Categories shows that Arethas was using Aristotle’s text primarily to expound within its framework the Neoplatonic ontology. In general, Arethas’ scholia to Aristotle express ambiguities in his attitude toward the ancient philosopher; although in his Letter to Stephanus written about 907 (Westerink 1968, vol. 1, p. 325, line 15-27) he gives the impression of being close to Aristotle, his commentaries and some other letters (e. g. Letter to Niketas, written after 907) demonstrate Arethas’ criticism of Aristotle.

Arethas frequently involved scribes who excerpted and adapted material from earlier commentaries, particularly in the case of the logical treatises that were widely used in higher education in Byzantium. Although Arethas’ attitude to Aristotle and his logic is not very clear, he is a critic of Aristotle on doctrinal issues that are considered fundamental to Christian thought (the theory of soul, substance). On the other hand with the help of Porphyry and the Neoplatonic commentators, he understands the importance of Aristotle’s doctrine of categories.

Arethas’ Christian thought and his distance from Aristotle can be seen in his treatment of the notion of the rational soul. Arethas rejects the doctrine of rational soul, which he considers to be Aristotle’s, but which is actually never used by Aristotle himself. Arethas does not realize this mistake, which resulted from a misreading of The Nicomachean Ethics (Letter to Niketas). The expression logike psyche comes from Neoplatonic thought (Plotinus, Proclus) and was discussed by Arethas and other Christian thinkers. Arethas’ teaching on the rational soul is in agreement with the teachings of the Greek Fathers (Gregory of Nyssa) that the soul and the body are created simultaneously and their coexistence is definite from the very beginning. The rational soul does not have the attributes of the sperm or of the father of the rational being, but of God, because it is produced by God (Benakis 1972).

Arethas, just like many other Byzantine commentators after him (Psellos, Blemmydes, Sophonias, George Scholarios), raises the issue of the number of Aristotle’s categories. According to Arethas, the category of substance should be placed first, because substance is by nature prior to the other categories. The priority of substance is characterized by indestructibility (substance is not destroyed when other categories are, but with the destruction of substance all categories are destroyed), self-existence (substance is prior to what exists depending on other things), and singleness (substance is single, the accidents are many, and one always precedes many). Arethas analyzes, too, the order of the categories and he reverses Aristotle’s order to introduce the category of quality before the category of pros ti, which indicates the influence of Neoplatonic commentators (lerodiakonou 2005).

Moreover, Arethas’ scholium on Categories 2a11-19 provides him with the grounds to replace Aristotle’s distinction between the first and second substance with the Neoplatonic sixfold variety of the meanings of the notion of substance (Anton 1997). Arethas redefines substance in a theological way and he endeavors to incorporate the Plotinian theory of hypostatic beings. He thus moved away from his earlier Aristotelianizing Neoplatonic treatment of the Categories and tried to define substance as a genus of being in order to accommodate the divine being. He classified substances into simple substances, that is, souL, intellect, and God, and complex substances, that is, matter and species.

See also: > Aristotelianism in the Greek, Latin, Syriac, Arabic, and Hebrew Traditions > Philosophy, Byzantine > Photius of Constantinople > Platonism