pre-socratic

Soul (ψυχή) often equated with life-force or breath.

"all things are full of gods" Aristotle, De Anima 411a7, quoting Thales

Heraclitus: the soul has a deep, unexplored structure and needs to be “kindled” like fire to become wise

Pythagoreans: soul is immortal and transmigrates (metempsychosis).

Empedocles and Anaxagoras introduce NOUS (mind) as a soul-like power.

No strict separation yet between physical and spiritual dimensions.

Care for the soul

Socrates says:

ΤΟ ΕΠΙΜΕΛΕΙΣΘΑΙ ΕΑΥΤΟΥ ΕΣΤΙΝ ΕΠΙΜΕΛΕΙΣΘΑΙ ΤΗΣ ΨΥΧΗΣ / To care for oneself is to care for the soul.

ΟΥ ΤΑ ΧΡΗΜΑΤΑ ΥΜΑΣ ΠΟΙΕΙΝ ΑΛΛΑ ΤΗΝ ΨΥΧΗΝ ΩΣ ΑΡΙΣΤΗΝ ΕΙΝΑΙ / Care not for your bodies or your wealth so much as for the best possible state of your soul.

the concept of EPIMELESTHAI ("care for one's self / care for the soul) is key concept of classical philosophical tradition

Soul as immortal charioteer

"Of the nature of the soul, though her true form be ever a theme of large and more than mortal discourse, let me speak briefly, and in a figure. And let the figure be composite—a pair of winged horses and a charioteer. Now the winged horses and the charioteers of the gods are all of them noble and of noble descent, but those of other races are mixed; the human charioteer drives his in a pair; and one of them is noble and of noble breed, and the other is ignoble and of ignoble breed; and the driving of them of necessity gives a great deal of trouble to him..." (Plato, Phaedros)

Soul as mover of the body

"... I will endeavour to explain to you in what way the mortal differs from the immortal creature. The soul in her totality has the care of inanimate being everywhere, and traverses the whole heaven in divers forms appearing—when perfect and fully winged she soars upward, and orders the whole world; whereas the imperfect soul, losing her wings and drooping in her flight at last settles on the solid ground—there, finding a home, she receives an earthly frame which appears to be self-moved, but is really moved by her power; and this composition of soul and body is called a living and mortal creature." (Plato, Phaedros)

Aristotle :: Soul as form

Aristotle’s theory of soul is grounded in hylomorphism, the idea that all living beings are composites of matter (hyle) and form (morphe).

The body is the matter, the potentiality.
The soul is the form, the actuality of a living body.
The soul is not a separate substance, but the essence that gives life and organization to the body.

The soul is the actuality of a body that has life potentially.” (De Anima, II.1)

Hierarchical model of the soul

Nutritive Soul (Vegetative Soul):: Found in plants :: Nutrition / Growth / Reproduction :: most basic type of soul

Found in animals. :: Includes all the capabilities of the nutritive soul, plus: Sensation (sight, hearing, etc.) / Appetite and desire / Locomotion (movement)

Rational Soul :: Unique to humans, able to universals and is capable of theoretical knowledge. Includes both the nutritive and sensitive capacities, and Reason (logos) / Abstract thinking / Deliberation and choice

+ intellect (NOUS) composed of passive intellect (NOUS PATHETIKOS) and active intellect (NOUS POIETIKOS)

Hellenistic

Epicureans: soul is material, composed of fine atoms.

No afterlife: soul dissolves at death—no reason to fear it.

Stoics: soul is PNEUMA, a fiery breath pervading the body.

Soul contains HEGEMONIKON (governing principle) in the heart.

Ethics grounded in cultivating (EPIMELESTHAI) rational soul in accordance with nature.

Neoplatonism

Neoplatonism is a philosophical school of late antiquity (3rd - 6th century AD). Neoplatonists position the soul in the middle of a strict metaphysical hierarchy:

Soul is a lower emanation from Nous (divine Intellect), which in turn comes from the One (the ineffable source).

Soul is the mediator between the intelligible world (Nous, Forms) and the sensible world.

Soul is partly divine but also linked to matter, and some souls descend too far and forget their origin.

The ultimate aim is the return (epistrophē) to the One via inner purification, contemplation, and ascent.

Islamic Philosophy

Soul (نَفْس, *nafs*) is a spiritual, immaterial substance.

Influenced by Aristotle, Neoplatonism, and Qur’anic revelation.

Avicenna: soul is simple, incorporeal, and individuated at creation.

Soul progresses through stages: vegetative, animal, rational.

Mystical traditions (e.g., Sufism) focus on purification of the soul.

Philosophical arguments for immortality and resurrection abound.

Christian Theology

Soul is created by God and infused at conception.

Augustine: soul seeks rest in God; image of God within the soul.

Soul is immortal, destined for salvation or damnation.

Soul's faculties: memory, understanding, will (trinitarian analogy).

Union with God is possible through grace and charity.

Body-soul dualism often influenced by Platonic models.

Scholasticism

Thomas Aquinas: soul is the form of the body (via Aristotle).

Soul has vegetative, sensitive, and rational powers.

Immortality of the rational soul is demonstrable by reason.

The soul subsists independently and survives bodily death.

Heavily influenced by Aristotle and Christian doctrine.

Debates on when and how the soul is infused in the embryo.

Renaissance & Early Modern

Renewed interest in Platonism and Hermetic soul cosmologies.

Descartes: radical dualism—soul (res cogitans) and body (res extensa).

Human soul seen as seat of reason, will, and self-consciousness.

Debates emerge over animal souls and mechanistic bodies.

Mystical and esoteric views on soul persisted alongside rationalism.

Soul increasingly tied to the concept of personhood.

Cogito ergo sum

"Accordingly, seeing that our senses sometimes deceive us, I was willing to suppose that there existed nothing really such as they presented to us; And because some men err in reasoning, and fall into Paralogisms, even on the simplest matters of Geometry, I, convinced that I was as open to error as any other, rejected as false all the reasonings I had hitherto taken for Demonstrations; And finally, when I considered that the very same thoughts (presentations) which we experience when awake may also be experienced when we are asleep, while there is at that time not one of them true, I supposed that all the objects (presentations) that had ever entered into my mind when awake, had in them no more truth than the illusions of my dreams. But immediately upon this I observed that, whilst I thus wished to think that all was false, it was absolutely necessary that I, who thus thought, should be something; And as I observed that this truth, I think, therefore I am, was so certain and of such evidence that no ground of doubt, however extravagant, could be alleged by the Sceptics capable of shaking it, I concluded that I might, without scruple, accept it as the first principle of the philosophy of which I was in search."

(Rene Descartes, Discourse on the Method, 1637)

Empiricism and Materialism

Soul increasingly reduced to observable mental or bodily processes.

Locke: denies innate ideas—soul as tabula rasa, a passive receiver.

Hume: rejects a persistent self; mind is a bundle of perceptions.

La Mettrie: human soul is an effect of bodily mechanisms (*L'homme machine*).

Diderot and French materialists view soul as an illusion of matter in motion.

Mind-body dualism increasingly replaced by monist materialism.

L'homme machine

The human body is a machine which winds its own springs. It is the living image of perpetual movement. Without food, the soul pines away, goes mad, and dies exhausted. ...[H]eavy food makes a dull and heavy mind whose usual traits are laziness and indolence. ... everything depends on the way our machine is running.

(Julien Offray de La Mettrie, 1747)

Associationism

Soul or mind functions through the association of ideas.

David Hartley: vibrations in nerves correspond to mental associations.

Mind explained through natural laws, not metaphysical substances.

Emphasizes memory, habit, and experience over rational soul.

Bridge between empiricism and early psychology.

Shift from soul as essence to mind as structure of learned relations.

German Idealism & Romanticism

Soul is active, not passive—central to constructing experience.

Kant: we can never know "soul" as a thing-in-itself.

Fichte: ego (Ich) posits itself—soul as dynamic self-consciousness.

Schelling: soul and nature are aspects of the Absolute unfolding.

Hegel: soul partakes in Spirit (Geist), unfolding historically and dialectically.

Emphasis on development of the soul through culture and reason.

Panpsychism

All matter possesses some form of experience or consciousness.

William James: stream of consciousness is continuous, plural, and lived.

Rejects both materialism and soul-substance dualism.

Radical empiricism: consciousness is a basic feature of reality.

Panpsychism redefines soul not as a separate entity, but as pervasive sentience.

Mind is not isolated; world is interwoven with subjectivity.