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Summa Argument Builder

Master the art of the medieval disputatio

St. Thomas Aquinas structured every article of his Summa Theologiae like a formal debate: first the objections against his position, then a counter-argument (sed contra), then his own answer (respondeo), and finally replies to each objection. It's one of the most rigorous — and beautiful — ways to argue ever devised. Here you can learn the structure, test yourself, and build your own Summa-style arguments on fun modern topics.

1. The Question

Quaestio — "Whether..."

Every article begins with a question, always phrased as "Whether..." (Utrum). Aquinas frames it so that his own position is the affirmative answer. For example: "Whether God exists?" — Aquinas will argue yes.

2. Objections

Objectiones — "It seems that..."

Next come the objections — arguments against the position Aquinas will defend. He states these fairly and forcefully. Each begins with "It seems that..." (Videtur quod). These are the strongest arguments of his opponents, presented honestly. Usually 2–5 objections.

3. On the Contrary

Sed contra — "On the contrary..."

A brief counter-argument, usually citing Scripture, a Church Father, or Aristotle. This signals which side Aquinas will take. It's like a thesis statement backed by authority.

4. I Answer That

Respondeo — "I answer that..."

The heart of the article. Here Aquinas gives his own reasoned argument. This is where the philosophical and theological heavy lifting happens. It's his positive case.

5. Replies to Objections

Ad primum, Ad secundum... — "To the first, I reply..."

Finally, Aquinas goes back and answers each objection one by one. He never ignores an objection — he either shows why it's wrong, or explains how it's compatible with his position after all. This is intellectual charity at its finest.

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Example: Summa Theologiae I, Q.2, Art.3 — Whether God exists?

Objection 1: It seems that God does not exist; because if one of two contraries be infinite, the other would be altogether destroyed. But the word "God" means that He is infinite goodness. If, therefore, God existed, there would be no evil discoverable; but there is evil in the world. Therefore God does not exist.

Sed contra: It is said in the person of God: "I am Who am." (Exodus 3:14)

Respondeo: The existence of God can be proved in five ways. The first and more manifest way is the argument from motion...

Reply to Objection 1: As Augustine says: "Since God is the highest good, He would not allow any evil to exist in His works, unless His omnipotence and goodness were such as to bring good even out of evil."

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