Key Ideas
The Five Ways to God.
God as subsistent being itself.
Natural law and the four kinds of law.
The virtues — cardinal and theological.
Just war and the principle of double effect.
Written as a textbook “for beginners” (!), the Summa has three parts: the First Part on God and creation; the Second Part (in two sections) on human action, virtue, law and grace — the return of rational creatures to God; and the Third Part on Christ and the sacraments, left unfinished when Aquinas stopped writing in 1273.
Each article follows the same pattern: the question; objections (usually three) against Aquinas’s view; sed contra (“on the contrary”), an authority; respondeo (“I answer that”), the body; and replies to each objection. The structure forces the reader to see the strongest case against the conclusion. See Thomas Aquinas and Scholasticism.
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related by shared connectionsScholasticism
The method and philosophy of the medieval universities — rigorous disputation, the reconciliation of faith and reason, and the absorption of Aristotle into Christian, Jewish and Islamic thought.
Averroes (Ibn Rushd)
Andalusian judge and philosopher — “the Commentator” on Aristotle — who defended philosophy against al-Ghazālī and argued that reason and revelation cannot contradict each other.
Dayānanda Sarasvatī
The Gujarati ascetic (1824–1883) who founded the Ārya Samāj with the cry “Back to the Vedas!” — rejecting idol-worship, caste by birth, and the Purāṇas, and calling for a rational Vedic religion, education for women and the reconversion of those who had left Hinduism.
Raja Rammohun Roy
The Bengali reformer (1772–1833) called the “father of modern India” — translator of the Upaniṣads as rational monotheism, founder of the Brahmo Samāj, campaigner against satī, and champion of modern education and a free press.
Candide
Voltaire’s comic philosophical tale, in which a naïve young man and his optimist tutor suffer every disaster the eighteenth century could offer — ending with “we must cultivate our garden”.
Critique of Pure Reason
Kant’s masterwork, asking what reason can know without experience — and answering that it can know the forms of all possible experience, but nothing beyond.