Psychology

Another potential conflict between Aristotelian natural philosophy and Christianity is created by Aristotle’s definition of the soul as ‘‘the first actuality of a natural body,’’ which seems to rule out the possibility of its being immortal. To a large extent this conflict was suppressed by the Neoplatonic exegesis of Aristotle. Especially Philoponus’ commentary on the De anima was studied throughout the Greek Middle Ages, although virtually unknown in the Latin West. Philoponus thought that what Aristotle meant to say was that the vegetative soul is wholly inseparable from the body, whereas the irrational soul is separable from the gross body, though inseparable from the pneuma, and thus mortal, and the rational soul (which Philoponus equates with the intellect), the substance of which transcends all body, but some of whose activities are bound up with the human body, is wholly separable and thus immortal. This interpretation was adopted by numerous writers, including Theodore Metochites in his commentary on the De anima (c. 1320), where he explained that Aristotle’s famous query of whether the soul is analogous to a sailor on a ship was meant to suggest that some part of the soul may per se be wholly separable from the body, even though it is inseparable qua the actuality of that body, in the same way that the sailor is inseparable qua sailor. Metochites also claimed in his Semeioseis gnomikai that Aristotle’s cosmological argument in Physics 7 and 8 for the existence of an unmoved mover entails the existence of a self-moved soul a la Plato, and that the latter must necessarily exist forever. The inferences are astonishing and apparently fallacious, but can at least be partly defended on the assumption that Aristotle’s ban on self-movement is only applicable to physical change.

Metochites was aware that Aristotle had been taken by some interpreters to deny the immortality of the soul, but so entrenched was the Neoplatonic reading that even George Gemistos Plethon, who tried his best in his De differentiis (1439) to document the inferiority of Aristotelian to Platonic doctrine, conceded that Aristotle made the human intellect immortal. He did, however, think that the Stagirite was inconsistent in affirming, on the one hand (in De gen. an. 2.3), that the intellect exists prior to the body, and denying, on the other hand, that learning can be called “recollection”. In his reply, George (Gennadios) Scholarios explained that Aristotle’s view should be understood in terms of a transition from potentiality to actuality: the soul is the fulfilment of the body, and the intellect is its only immortal part. It is prior to the body in substance, not in time. Plethon retorted that on Scholarios’ and Aristotle’s own showing (De caelo 1.12) an immortal intellect must be ungenerated. Anyone, he contended, who regards the human soul as immortal must admit that it is uncreated in time as well as subject to reincarnation. Otherwise, something which according to Aristotle’s arguments in Physics 3.5 is impossible will follow: there will be an infinite number of simultaneously existing souls. This objection had been previously raised by Philoponus (In De anima 3, 38.90-96).

See also: > Aristotelianism in the Greek, Latin, Syriac, Arabic, and Hebrew Traditions > Aristotle, Arabic: Physics

>  Change and Motion > De caelo, Commentaries on Aristotle’s > De generatione et corruptione, Commentaries on Aristotle’s > George Gemistus Plethon > George Pachymeres > Gregory Palamas > John Philoponus

>  Medicine, Byzantine > Metaphysics, Byzantine

>  Michael Psellos > Natural Philosophy > Natural Philosophy, Arabic > Natural Philosophy, Jewish

>  Nikephoros Blemmydes > Nikephoros Choumnos

>  Nikephoros Gregoras > Parva naturalia, Commentaries on Aristotle’s > Philosophical Psychology, Byzantine

>  Philosophy, Byzantine > Theodore Metochites > Time