On the Trinity
De Trinitate — Augustine's mature systematic theology of the triune God, in fifteen books
Tradition: Latin Christianity / Augustinian theology
The Trinity in itself, the Trinity in the human mind — the most sustained patristic analysis of God as three persons, one being
On the Trinity is Augustine's most ambitious systematic theological work, composed in stages from c. 399 to c. 419. The first seven books expound the Nicene Trinitarian doctrine through close reading of Scripture and response to Arian and modalist heresies. The second half (books 8–15) develops the famous "psychological analogies" — the image of the Trinity in the human mind (memory, understanding, will) — that shape every later Western Trinitarian theology. The work is the principal Latin source for the doctrine of the divine simplicity, the procession of the Holy Spirit (the filioque controversy), and the relation between divine being and the human mind. Aquinas's Trinitarian theology (Summa I.27–43) is in continuous dialogue with this work.
Author
Editions cited
- The Trinity (Edmund Hill, OP; New City Press, 2nd ed. 2015 — Works of Saint Augustine)
- On the Trinity (Stephen McKenna, Catholic University of America, 1963)
School Embodiments
On the Trinity is one of the principal Latin patristic sources of the Catholic Trinitarian tradition. Aquinas's questions on the Trinity in the Summa work systematically through Augustine's arguments.
"Without the Trinity nothing can be known about the Trinity." (De Trinitate XV.7.10)
Calvin's Trinitarian theology (Institutes I.13) reads De Trinitate carefully. The Western filioque doctrine and the psychological analogies shape Reformed orthodoxy.
"He who knows how to love himself loves God." (De Trinitate XIV.14.18)
Luther, as an Augustinian friar, treats On the Trinity as authoritative for the doctrine of God. The Lutheran confessions reflect Augustinian Trinitarian theology.
"The Father loves the Son with the same Spirit with which the Son loves the Father." (De Trinitate XV.27.50, paraphrasing)
The psychological analogies and the doctrine of divine simplicity reflect Augustine's sustained engagement with Plotinian metaphysics. The Father-Son-Spirit hierarchy has structural affinities with the One-Nous-Soul.
"What is more certain than that we are, know that we are, and love this being and knowing?" (De Trinitate XIV.4.6, anticipating Descartes)
A conversation partner rather than a full embodiment: Orthodox theology contests the Augustinian psychological analogies and the filioque doctrine but engages De Trinitate as a major Western theological text.
"The Holy Spirit is principally from the Father, and yet from the Son as well." (De Trinitate XV.17.29, the filioque-supporting passage)
The psychological analogy of the Trinity as memory, understanding, and love became the philosophical core of later Christian personalism: the human person as imago Trinitatis.
"There is, then, this trinity of mind, knowledge, and love." (De Trinitate IX.12.18)
Augustine's argument from self-evident inner certainty ("si fallor sum" — if I am mistaken, I exist) is the explicit precursor of Descartes's cogito.
"Si enim fallor, sum" — "If I am mistaken, I am." (De Trinitate XV.12.21)
Augustinian tradition.
Internal Tensions
The Augustinian psychological analogies have been criticised by Orthodox theologians (especially in the twentieth-century retrieval through Lossky and Zizioulas) as anthropocentric and as the philosophical root of the filioque controversy that split the Eastern and Western churches. Modern Catholic theology has engaged this critique seriously (Rahner's Rule, the social-Trinitarian movement).
I. Time
God is eternal in the Boethian sense (anticipated here); created time runs linearly toward the eschaton. The Trinity is timeless in itself; its operations in creation are temporal.
Attributes
II. Space
God is everywhere by essence, presence, and power without being spatially located. Standard Christian-cosmological background.
Attributes
III. Matter
Created good. Not the focus of the treatise.
Attributes
IV. Observer
The human mind is the image of the Trinity. Embodied, plural, both active (in reasoning toward God) and passive (in receiving illumination). Knowledge of the Trinity is partial in this life, total in the beatific vision.
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V. Energy
Standard medieval doctrine of God's continuous sustenance.
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VI. Information
God's knowledge is total and personal. The inscribed record of every creature is in the divine mind. Personal information is conserved across death.
Attributes
Personas that cite this work
Personas with the nearest attribute fingerprint
Historical figures whose own classification on the same six-dimensional grid lands closest to this work's. Computed by attribute-agreement on coordinates both address.
Computed school proximity
The work's attribute fingerprint scored against all schools using the same quiz scorer. Useful as a sanity check on the hand-curated embodiments above.
How On the Trinity resolves each dilemma
51 resolved positions across 4 dimensions, including 10 distinctive where the majority of schools go the other way · 6 unaligned.
Each dimension is sorted so minority positions come first. Mainstream positions are folded into an expandable list.
Time · 9 dilemmas · 3 distinctive
Persistence, the future, and the direction of becoming.
6 mainstream positions
Matter · 7 dilemmas, all mainstream
Observer · 37 dilemmas · 5 distinctive
Mind, agency, and the knower's relation to the known.