Faith and reason

Theistic religions typically claim an authoritative source of revealed truth, and philosophers within them have asked what revelation adds to what reason can discover, and what to do when the two seem to disagree. In Baghdad al-Kindi welcomed Greek philosophy as truth “from wherever it comes”. Al-Ghazali and Averroes later argued over how far the philosophers’ demonstrations should govern the reading of the Qur’an. In the Latin West Augustine saw faith as seeking understanding, and Aquinas divided truths about God into those reason can prove and those only revelation can teach.

In India the question took a different shape. For the Vedānta thinkers Śaṅkara and Madhva, scripture itself gives knowledge that perception cannot reach, and the argument was over how it fits with perception and inference. Śaṅkara accepted nonduality on the authority of the Upaniṣads, while Madhva insisted that scripture be read in keeping with everyday experience.

In modern Europe Spinoza set faith and philosophy in separate spheres, Kant restricted knowledge “to make room for faith”, and Kierkegaard held that faith centres on a paradox that reason cannot understand, and that reason cannot fully justify it.

Through time

4th century CE

Augustine

354–430 CE · Western

Faith comes first in time but understanding ranks higher: “faith seeks, understanding finds”. Reason needs the authority of Scripture and the Creed to keep it from going astray, yet choosing whose authority to trust is itself a reasonable decision.

About 400 years later

8th century CE

Śaṅkara

fl. 700–800 CE · Indian

The nonduality of self and brahman can’t be proved by independent reasoning; Śaṅkara accepted it on the authority of the Upaniṣads alone. Reasoning still has work to do: making sense of the scriptures, harmonising their passages, defending their teaching and refuting rivals.

9th century CE

al-Kindi

c. 800 – c. 870 CE · Arabic and Islamic

Truth should be welcomed “from wherever it comes”, even from foreign peoples, so Greek philosophy is no threat to Islam. Al-Kindi used it to defend and explain Islamic teaching, reading Qur’anic verses on creation from nothing and on the heavens through philosophical argument.

11th century

al-Ghazali

c. 1056 – 1111 · Arabic and Islamic

A valid demonstration is never wrong, so where one disproves the literal sense of revelation, the text must be read allegorically. But the philosophers’ arguments for an eternal world and two other doctrines fell short of demonstration, so revelation stood, and teaching them was unbelief.

12th century

Averroes

1126–1198 · Arabic and Islamic

Philosophy belongs at the heart of religious reflection, because demonstration can’t disagree with the religious law: “truth does not oppose truth”. Philosophers alone can bring out scripture’s hidden meanings, while rhetoric and dialectic lead others to the same truth by other paths.

Drew on al-Ghazali

13th century

Thomas Aquinas

c. 1225 – 1274 · Western

Natural reason can prove that God exists, but not truths such as the Trinity and the incarnation, which had to be revealed for our salvation. The two can’t truly conflict: anything in philosophy contrary to the faith is “an abuse of philosophy, due to a failure of reason”.

Drew on Augustine and Averroes

Madhva

c. 1238 – c. 1317 · Indian

The Vedas reveal a realm beyond the senses, but we could not know even them unless perception and inference were valid in themselves. So scripture must be read in keeping with everyday experience, and it can’t teach that the self and brahman are one, which experience contradicts.

Drew on Śaṅkara

About 400 years later

17th century

Baruch Spinoza

1632–1677 · Western

Scripture teaches obedience, not knowledge, and the prophets were pious rather than gifted philosophers. Reason and faith occupy separate spheres, so the freedom to philosophise does no harm to true religion, and the Bible should be interpreted from itself, as nature is studied.

18th century

Immanuel Kant

1724–1804 · Western

Speculative reason can’t give us knowledge of God or immortality, since our knowledge reaches only appearances. “I had to deny knowledge in order to make room for faith”: belief in God, freedom and immortality is justified, but on strictly moral grounds.

19th century

Søren Kierkegaard

1813–1855 · Western

The incarnation, the “Absolute Paradox”, is something human reason can’t understand, so it confronts us with a choice between faith and offence. Neither can be fully justified by reason, though it is doubtful he meant that faith believes a logical contradiction.

Through time

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