BookAges 16–18
Summa Theologiae (selections)
St. Thomas Aquinas
Catholic
The five ways (Ia q.2), the treatise on the virtues (IIa-IIae). A good annotated edition is essential.
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Related quotes from the canon
“The existence of God can be proved in five ways.”
— St. Thomas Aquinas, Summa Theologiae, Ia, Question 2, Article 3