How the arguments fit together
Begin with being, act, potency, causality, and participation. Then follow those principles into anthropology, ethics, law, grace, Christology, and sacramental theology.
Argument map
Aquinas's Major Arguments
A routed study map for the most important arguments and doctrines in Aquinas, with each page connected to the works where the argument is most visible.
Arguments
20
Linked works
25
Reading method
Move from principle to source text
Primary works stay beside the arguments
Each argument page links to Aquinas's major works so the study path does not become a list of detached claims.
Go to St. Thomas' WritingsStudy the arguments
Natural theology
The Five Ways for God's existence
Five concise demonstrations from motion, efficient causality, contingency, degrees of perfection, and final order.
Study this argumentMetaphysics
Act and potency
Change is intelligible because a being can possess a real capacity that is brought into actuality.
Study this argumentMetaphysics
Essence and existence
In creatures, what a thing is and that it exists are distinct; in God they are identical.
Study this argumentDivine attributes
God as Pure Act
God has no unrealized potency, and so is not changeable, composite, dependent, or perfectible.
Study this argumentDivine attributes
Divine simplicity
God is not composed of parts, matter and form, essence and existence, substance and accident, or genus and difference.
Study this argumentTheological language
Analogy of being and language
Names such as good, wise, and being apply to God and creatures neither univocally nor merely equivocally, but analogically.
Study this argumentMetaphysics
Participation metaphysics
Creatures possess being, goodness, truth, and perfection by participation, while God possesses them essentially.
Study this argumentNatural philosophy
Final causality and teleology
Natural powers and actions are intelligible because they are ordered toward ends.
Study this argumentMoral theology
Natural law
Natural law is the rational creature's participation in eternal law, ordered by the first principle that good is to be pursued and evil avoided.
Study this argumentMoral theology
Virtue ethics and beatitude
Human fulfillment lies in happiness, ultimately the vision of God, and the virtues order powers toward that end.
Study this argumentMethod
Faith and reason
Reason can know some truths about God, while revelation gives truths beyond reason; genuine truth cannot contradict genuine truth.
Study this argumentAnthropology
The soul as form of the body
The human person is one substance composed of body and rational soul; the soul is subsistent but naturally united to the body.
Study this argumentAnthropology
Intellect and knowledge
Human knowledge begins in sense experience, while the intellect abstracts universal intelligible forms from particulars.
Study this argumentTheology and action
Free will and divine providence
God governs all things as universal cause, while human beings act freely as real secondary causes.
Study this argumentTheological anthropology
Grace and nature
Grace heals and elevates nature rather than destroying it, raising the person toward supernatural beatitude.
Study this argumentDogmatic theology
Christology
Christ is one divine person with two natures, divine and human, and the Incarnation is fitting for human salvation.
Study this argumentDogmatic theology
Sacramental theology
Sacraments are instrumental causes of grace, with the Eucharist receiving special treatment through transubstantiation.
Study this argumentMoral and political theology
Just war theory
War can be just only under conditions such as legitimate authority, just cause, and right intention.
Study this argumentPolitical theology
Political authority and the common good
Political life is natural to human beings, and law and authority should be ordered to the common good.
Study this argumentMoral and political theology
Property and economic justice
Private property is lawful and useful, but its use remains ordered to the common good and the needs of others.
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