Summa Theologica

What Is the Summa Theologica About?

Aquinas designed the Summa as a comprehensive guide for theology students. It's organized into three parts: God and creation, the moral life (virtues and vices), and Christ and the sacraments.

Each section uses a rigorous format: Aquinas states a question, presents objections to his position, gives his answer ("I answer that..."), and then replies to each objection. This dialectical method — reminiscent of Plato and built on Aristotle — makes the Summa a masterclass in careful reasoning.

Among its most famous arguments: the Five Ways (five proofs for God's existence), the nature of law (natural law, human law, divine law), and the analysis of virtues that builds directly on Aristotle's Nicomachean Ethics.

Why the Summa Theologica Still Matters

• Faith and reason: Aquinas demonstrated that philosophy and theology are complementary, not contradictory — a claim still debated today.
• Natural law: His theory of natural law influenced the Declaration of Independence, the U.S. Constitution, and modern human rights discourse.
• The Five Ways: Aquinas' arguments for God's existence remain the starting point for philosophical theology.
• Intellectual method: The Summa models how to argue fairly — always presenting the strongest version of opposing views before responding.

Why Classical Schools Teach It

Selections from the Summa are read in advanced Great Books programs. At Saints Classical Academy, Aquinas is studied in the rhetoric stage as the culmination of medieval thought.

• Synthesizes the classical tradition — Plato, Aristotle, Augustine — with Christian revelation
• Develops rigorous skills in logical argumentation and dialectic
• Essential for understanding natural law, virtue ethics, and Western political philosophy
• Pairs with Dante's Divine Comedy as the intellectual summit of the medieval curriculum