ris3n's Apologetics Codex

Person

Thomas Aquinas

Thomas Aquinas was a Dominican friar, theologian, and philosopher. He brought Aristotle's philosophy together with Christian theology, and that fusion defined Western scholasticism. In ris3n's notes he is the most-cited philosopher (5 of 18 Philosophy and Logic notes). He shows up on truth as correspondence, scholastic predication, faith as a kind of knowledge, and the rational grounds of theological inquiry.

Themes

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  • Truth as correspondence. Aquinas's formula is the standard way Christian philosophers state the correspondence theory.
  • Faith and reason. Theological knowledge is rational. Revelation goes beyond natural reason but does not contradict it.
  • Predication and being. Aquinas builds Aristotle's categories into a full account of how words and thoughts map onto reality.
  • Evil as privation. Evil is not a positive thing. It is the absence of a good that should be there. So evil is not a real property in the way other properties are, and this is a classical reply to the Problem of Evil.

Mentions in Quick-Glance Reference Guide to Aquinas Five Ways (ris3n)

  • This source focuses on Aquinas. It walks through each of the Quinque Viae (Five Ways) from Summa Theologica I, q. 2, a. 3 as a clear syllogism with inference rule, modality, deeper metaphysical layer, objections and replies, definitions, the scriptural sed contra, and patristic and philosophical authorities.
  • The source follows the contemporary Thomist revival (Feser, Oderberg). It treats the Five Ways as live arguments, not historical leftovers.
  • Each Way ends in the classical-theist God under a different angle: pure act (Actus Purus), uncaused cause, necessary being, maximum being, and intelligent director. All converge on ipsum esse subsistens (Ipsum Esse Subsistens).
  • The source highlights the Thomistic toolkit the codex should make explicit: the Act and Potency distinction, Per Se vs Per Accidens Causation, Final Causality, and the doctrine of analogy.

Connection to codex concepts (added 2026-04-28 bulk extraction)

The 2026-04-28 §5.4 extraction built 99 new concept hubs. Many of them name Aquinas as the scholastic synthesizer across metaphysics, epistemology, free will, and Christology. Top references:

  • Theories of Truth, De Veritate Q.1: veritas est adaequatio rei et intellectus, "truth is the conforming of thing and intellect." The classical Christian statement of correspondence.
  • Necessary vs Contingent Being, Aquinas's Third Way (contingency) and the broader scholastic account. A "central plank of Christian metaphysics from Augustine through Anselm, Aquinas..."
  • Principle of Sufficient Reason, Anselm and Aquinas hold an implicit PSR in their cosmological arguments, though they do not state it as a general principle.
  • Foundationalism, moderate foundationalism in scholastic form. Sense experience plus self-evident principles (Aristotle's Posterior Analytics) form the foundation. Revealed truths are accepted on God's testimony.
  • Empiricism, Summa Theologiae I.84.6 adopts Aristotle's empirical principle while keeping the active intellect's role.
  • Rationalism, moderate empiricist who still defends rational demonstration.
  • Epistemology, moderate empiricism plus revelation. Set alongside Plantinga's warrant.
  • Substance Dualism, Summa Theologiae I.75-89: a hylomorphic-dualist view (the soul is the form of the body, but is also subsistent and immortal).
  • Property Dualism, hylomorphic dualism (Eleonore Stump, Feser) presented as a middle path between substance dualism and physicalism.
  • Final Causality, Aquinas as the Christian transmitter and developer of Aristotle's four-causes scheme. Foundation of the Fifth Way.
  • Modal Logic, the Thomist background for talk about divine attributes. Classical scholasticism uses modal categories.
  • Compatibilism, Aquinas on some readings. A voluntary act comes from the agent's own intellect and will, even though the intellect is drawn by the good it sees.
  • Libertarian Free Will, Aquinas listed (with Augustine, Arminius, Craig, Plantinga) on the libertarian side.
  • Predestination, Foreknowledge vs Causation, Aquinas takes the Boethian eternalist solution. Anselm picks it up too. It remains a leading contemporary Christian solution.
  • Molinism, Aquinas as comparison case. Bañezian / Thomist predestination is the Dominican counter-position to Molinism.
  • Penal Substitutionary Atonement, Aquinas joins Anselmian satisfaction to merit. The medieval Catholic mainstream framing.
  • Pantheism, Ipsum Esse Subsistens (Aquinas's account of God's being) explicitly set against pantheist identity-theism.
  • Materialism, Christian metaphysics is anti-materialist on the whole. Hylomorphic Thomism is a primary alternative.
  • Idealism, mainstream Christian metaphysics (Aquinas, Augustine, the Reformed tradition) holds to realism rather than Berkeleyan idealism.
  • Laws of Logic, classical theism (Augustine, Aquinas) holds that logic flows from God's eternal, rational nature.
  • Mosaic Authorship of the Pentateuch, listed (with Irenaeus, Origen, Jerome, Augustine, Luther, Calvin) as affirming Mosaic authorship as received tradition.
  • Critical Thinking Christian Framework, Summa Theologiae I, qq. 1-2 on the use of reason in theology.
  • Biblical Hope, Biblical Love, Biblical Forgiveness, Biblical Stewardship, Summa Theologiae II-II on charity (qq. 23-46), hope (qq. 17-22), penance (III, q. 86), and stewardship as Christian virtues.
  • Mary Sinless, Aquinas's middle position on the Immaculate Conception. Duns Scotus's preventive-redemption framework later resolved it.
  • Deductive Reasoning, Aquinas's Five Ways and Kalam are the standard deductive theistic arguments.
  • Presuppositionalism, Aquinas's natural-theological foundationalism is a contrast position to Van Tilian presuppositionalism.

Summa Theologiae I qq. 27-29, the Trinitarian framework (added 2026-05-01)

The ingest of Scholastic Answers, IRREFUTABLE The Holy Trinity (clipped) highlights Aquinas's systematic treatment of the Trinity in ST I qq. 27-43. This treatment is the structural template for all Latin-Thomist Trinitarian theology and for much of classical Reformed and contemporary Catholic systematics.

The ladder of qq. 27-30 follows the metaphysical order of explanation:

  • q. 27, On the procession of divine Persons. God has two faculties capable of immanent action, intellect and will. Each one grounds a procession: the intellectual generation of the Word, and the volitional spiration of Love.
  • q. 28, On the divine relations. Each procession grounds two relations (subject-to-terminus, terminus-to-subject), giving four real relations: paternity, filiation, active spiration, and passive spiration. Aquinas argues that relation, alone among the categorical accidents, can be predicated of God properly and not just by analogy. The reason: relation's propria ratio (esse ad, "order to another") does not modify its subject.
  • q. 29, On the divine Persons. Following Boethius's definition (naturae rationalis individua substantia), Aquinas defines a divine Person as a subsistent relation in the divine nature. Personhood is the incommunicability of an individual rational nature, not self-consciousness.
  • q. 30, Plurality of Persons in God. The four relations make up three Persons, not four. Active spiration is not relatively opposed to paternity or filiation, and only relative opposition produces real distinction.
  • q. 32 a. 1, Aquinas explicitly denies that the Trinity can be proved from natural reason. It is a revealed mystery. Natural theology can show it is coherent, but cannot generate it. This is the methodological rule all Latin-Thomist Trinitarian work follows.
  • q. 36, On the procession of the Holy Spirit. Aquinas's defense of the Filioque (see Filioque) by relative opposition. Without the Son being the subject of active spiration, there would be no way to distinguish the terminus of intellection from the terminus of volition.

This framework carries the weight of Relation (Thomist Metaphysics), Filioque, Trinity Coherence Defense (Latin-Thomist), and the Latin side of Trinity. The contemporary Latin-Thomist tradition continues to develop these qq. (Eleonore Stump, Brian Davies, Edward Feser, Gilles Emery's The Trinitarian Theology of St Thomas Aquinas).

See also