Aion

The book draws extensively on the Gnostic-Neoplatonic tradition (Valentinus, the Pleroma) and the Renaissance Neoplatonic hermetic tradition, which Jung reads as preserving psychological material orthodox Christianity excluded.

"The Gnostics had a feel for the totality of the psychic phenomena — for what we should now call the wholeness of the Self. The orthodox tradition lost this and never fully recovered it." (Aion, ch. 13)

Alchemy — the principal subject of Jung's late work — is treated as a symbolic articulation of the individuation process, and Aion devotes its central chapters to the symbolism of the lapis and the alchemical opus.

"The alchemical opus is the work of self-knowledge; the lapis is the symbol of the Self." (Aion, ch. 14)

Jung engages the Catholic theological tradition with depth — particularly the dogma of the Assumption of Mary (declared 1950, while Jung was writing) — though he reads its symbolism in his own depth-psychological terms.

"The recent declaration of the Assumption is, for the psychologist, the most important religious event since the Reformation — a real movement of the unconscious into the canon of dogma." (Aion, ch. 7)

The Christ-symbol Jung analyses is the patristic-and-eastern Christ as much as the Western one — Jung found Eastern Orthodox theology more open to the symbolic-mythopoetic dimension.

"The Eastern Christian tradition has preserved a richer sense of the symbolic Christ than the rationalised West." (Aion, ch. 5)

The treatment of archetypes as objective psychic structures discernible across history is a form of Platonist-idealist psychology — the archetypes are real, not nominalist constructions.

"The archetypes are not concepts but irrepresentable structures of the psyche — they manifest in symbols that are themselves never the archetype but only its trace." (Aion, ch. 3)

The descriptive method — close attention to symbolic phenomena across Gnostic, alchemical, dream, and astrological sources — is phenomenological in the broad sense.

"We must take the symbolic material as it presents itself, without prematurely subjecting it to a theoretical framework." (Aion, ch. 4)

Jung is a psychological realist about archetypes — they are not mere social-constructions but features of the species's collective unconscious.

"The collective unconscious is as real as the body; the archetypes are as objective as instincts." (Aion, ch. 1)

Gnostic tradition — Jung draws extensively on Valentinian and Sethian sources.