Philosophy

Plethon is a Platonist, inspired in his interpretation of Plato mainly by Plutarch (first century CE), Numenius, Atticus (second century CE), Plotinus (third century), and Proclus (fifth century). Plethon maintains the agreement of Zoroastrian, Pythagorean, and Platonic philosophy (Book of Laws III.43, 252-6), which is reminiscent of Numenius’ claim about the diffusion of truth to ancient sages (fr. 1 Des Places; cf. Laws III.43, 253-256), and considers the Persian Magi to be disciples of Zoroaster and interpreters of his thought in the Chaldean Oracles, which explains his fascination with them (Athanassiadi 2002). Like Numenius and Plotinus, Plethon maintains the hierarchical structure of intelligible reality, while he also relates metaphysical principles with pagan gods and shows a tendency for religious prescriptions, which is characteristic of Proclus.

Plethon’s most important philosophical works are the De differentiis and the Book of Laws. More comprehensive is the Book of Laws, which must have been written over A long period of Plethon’s life. It is a loose and repetitive composition divided into three books, none of which focuses on a single theme; chapters on ethics and politics appear in books I and III, chapters on metaphysics occur in books I and II, while some chapters such as II.6, on fate, were probably independent treatises (Hladky 2007: 198-209). In the first chapter, Plethon argues that his work aims to present the laws and the best constitution according to which intelligent people should live in order to achieve happiness (LawsIII.43,248). Plethon maintains that human happiness cannot be determined unless one inquires first into the nature of human beings and the nature of the universe, where man lives (Laws I.1, 22), a view he also defends in his treatise On Virtues (A2, p. 3 Tambrun-Krasker). Accordingly, Plethon suggests that ethics depends on physics, and physics depends on theology.

Plethon maintains the Platonist division of reality into intelligible and sensible realms and argues for its hierarchical order. He adopts a Pythagorean and Plato-nist distinction of three kinds of essences. The first is the father or originator of everything else (Laws III.15, 96), which Plethon identifies with Zeus (Laws III.15, 96) and apparently also with the Form of the Good (III.35, 222) which is beyond being (Republic 509b), as can be inferred from his description according to which the first god is supremely one and simple (Laws III.15, 100), pre-eternal (propator, Laws III.35, 204), being itself (autoon; III.34, 132), good itself (autoagathos; Laws III.34, 132), and beyond being (hyperousios; I.5, 46). Noticeably, Plethon uses vocabulary found in Numenius (frs. 16, 17, 21 Des Places) and the Chaldean Oracles (XXXI-II). Like Numenius and Plotinus, Plethon maintains that the first god brings about a second entity, an image of himself (Laws III.15, 96-98), through whom the first god creates the universe (De differentiis X.336.20-23). This is the realm of the intelligible Forms, which is characterized by multiplicity (De differentiis X.337.7-13; Laws I.5, 56). The Forms are the immediate causes of the things in the sensible world (De differentiis X.341.39-342.1), yet God or Zeus is the ultimate cause of everything (Laws III.15, 102). Plethon identifies the Forms with the supra-celestial gods, who are divided into two kinds, the Olympian and the Titans (Laws I.5, 46-52). The final kind of essence is the soul, which is identified with the subcelestial gods (Laws I.5, 52-54). Each kind of essence generates an ontologically inferior entity (Laws III.15, 94-96, 102): the first God generates the intellect and the Forms, identifiable with a certain class of gods, they in turn generate lower gods, until we reach the demons and the mortal beings (Laws I.5, 52).

Plethon is a determinist, maintaining two axioms that ‘‘whatever occurs must necessarily do so from some cause’’ and that ‘‘every cause must produce whatever effect it may have in both a necessary and a determinate way’’ (De differentiis VIII, 332.24-334.4). Plethon relates the effect of the causes with the activity of the gods, arguing that the gods are the causes of everything that happens (Laws II.6, 64-66), with the first god, Zeus, in particular to be the source of necessity, as he is unchangeable (Laws II.6, 67). Plethon claims that the rejection of determinism leads to atheism (Laws II.6, 66), of which he accuses Aristotle (De differentiis VIII). Being confronted with the question of human freedom that his position entails, Plethon takes a view similar to that of the Stoics, arguing that man is free in his most rational part, yet this does not mean absence of necessity. This is imposed by the gods and the first god in particular, but it is always for the good since the first god is absolute goodness; man, being rational, can always decide to side with the divine necessity and live a good life, or not and be miserable (Laws II.6, 67, 72-74; Letter to Bessarion, Mohler 1942:I.462; Bargeliotes 1975; Hladky 2007:117-120). Accused by Bessarion that this is a Stoic view (Letter to Plethon II, Mohler 1942:III.464), Plethon refers to the role of the soul in Epinomis (Letter to Bessarion II, Mohler 1942:III.466).

Regarding cognition, Plethon argues that reason is the best and most divine criterion by means of which we can attain truth and achieve happiness (Laws I.2, 34). Also divine are the common notions by means of which we think, which Plethon apparently identified with the intelligible Forms, as can be inferred from the fact that in De differentiis X he argues that the Forms solve the problem of how man cognizes the essences of things. These forms or common notions are sown into the souls by the divine intellect, and this is how each soul has acquired reasons of things (Magian Oracles XVI; Hladky 2007:45).

Being a Platonist, Plethon defends the immortality of the soul and criticizes Aristotle for rejecting the Platonist position (De differentiis IX-X). Plethon adopts the Platonic view that man consists in a mortal and in an immortal part, which correspond to our animal and divine nature (Laws III.43, 246-8), and argues that man is the bond between the mortal and the immortal part of the universe (Laws III.43, 246, Summary of the Doctrines of Zoroaster and Plato, Alexandre Traite des Lois, 1858, 267). He argues that the soul uses an ethereal body as a means for moving into an actual body (Reply to Scholarios XXIX.474.25-30, Magian Oracles XV). Plethon adds some new arguments in support of the Platonic thesis in his two funeral orations on the empresses Cleope and Helen. He points out that this is an ancient belief widely accepted (On Cleope 171.7-172.8), and also claims that the desire on the part of humans for immortality suggests that this can be satisfied. Plethon further argues that humans would not be prepared to kill themselves, unless the human soul would survive, because no animal seeks its own destruction (On Cleope 173.9-174.4). Being the boundary (methorion) between the mortal and immortal world, man connects the two and contributes to the universal harmony (Laws III.43, 258-60; Hladky 2007:109).

Plethon’s view that man is composite of a mortal and an immortal part shapes also his ethics. Assuming that man is a creature of god and akin to its creator by virtue of reason (Laws III.34, 148), he claims that man can become like god, who is perfectly good (On Virtues A2:3), defending the view of the Theaetetus 176b that happiness consists in attaining assimilation to god (On Virtues A1, Laws II.6, 74, III.34, 144). Virtue is defined as ‘‘the disposition (hexis) according to which we are good’’ (On Virtues A1:1). Like Plotinus and later Neoplatonists, Plethon appears to distinguish between civic virtues, which benefit society (A11:12), and dianoetic virtues, pertaining to man’s immortal part. In the first category, he distinguishes four cardinal virtues in hierarchical order, prudence, justice, courage, and temperance. In order to acquire virtue, we must have a perfect understanding oF it as well as practice and training (A14:14). Yet the most eminent activity by means of which man comes close to the divine is contemplation (Laws III.43, 246-248).

Plethon’s political views are outlined in the Book of Laws and in his advisory orations to the emperor Manuel and the Despot of Mystras, Theodore. In the political orations and in his two funeral orations on the empresses Cleope and Helen, Plethon uses historical and mythological examples and talks about the Byzantines in a historical perspective, linking them with the Romans and the ancient Greeks. In his addresses to the imperial court, Plethon proposed economic, administrative, and military reforms in the organization of Peloponnese. Inspired by the Republic, Plethon argues for a three-tiered social structure, the ruling class (the imperial court), the service providers (e. g., merchants, retailers), and the laborers (e. g., farmers), while in his oration to Theodore, Plethon distinguishes three kinds of constitution, monarchy, oligarchy, and democracy, himself leaning towards an enlightened monarchy, that is, a ruler assisted with good counselors and relying on good laws. This appears to be at odds with the ideal constitution of the Republic, but perhaps Plethon considered the ruler and his advisors as the ruling class (Hladky 2007:10-12).

Plethon also had scientific, historical, and theological interests; he was the author of a geographical treatise (Diller 1937), of an astronomical manual (Tihon-Mercier), of a historical work on the aftermath of the battle of Mantineia (Maltese 1989), and of a theological treatise about the procession of the Holy Spirit, in which he defended the Byzantine position (Alexandre Traite des Lois 300-311). Scholarios’ accusations of Plethon for attachment to Proclus (Letter to the Exarch Joseph, Opera IV.153.23-24), commitment to, and diffusion of paganism, distort the profile of the complex thinker and should be resisted (Monfasani 1992, against Masai 1956; Woodhouse 1986). Plethon had an impact on Byzantines and Italian humanists. He probably introduced to Italy Strabo’s Geography, studied also by Christopher Columbus (Woodhouse 1986:183), and was responsible for the diffusion of the Chaldean Oracles to Ficino’s circle (Wilson 1992:91-92; Tambrun-Krasker 2006:9-33), who mentions Plethon in the preface of his translation of Plotinus’ Enneads.

See also: > Basil Bessarion > Demetrios Kydones