Kalām

Islamic speculative theology: the use of reasoned argument to defend and explain religious belief.

Also: kalam, ilm al-kalam, Islamic speculative theology, kalām cosmological argument, mutakallimūn

What it means

Kalām is the tradition of rational theological argument in Islam; its practitioners are the mutakallimūn. The name echoes kalām Allāh, 'the word of God'. It began by defending Islam against other faiths and later borrowed Greek dialectical methods. Its schools disagreed sharply: the Muʿtazila gave reason independence from revelation and defended human free will, while the Ashʿariyya took a middle path closer to traditional Sunni belief. Kalām also gave its name to a famous argument for God's existence: whatever begins to exist has a cause, and the universe began, since an actually infinite past is impossible. Al-Ghazālī gave it a classic formulation, and William Lane Craig revived it in recent philosophy of religion.

The questions it belongs to

• 1.8 Natural TheologyCan argument alone settle whether God exists?
• 1.2.1 Origins and First CauseDid anything ever start, or has it always been running?

Thinkers

• al-Ghazālī
• John Philoponus
• Bonaventure
• William Lane Craig

Traditions

• Islamic
• Medieval Christian
• Analytic

To read

• Deliverance from Error — Al-Ghazali
• The Incoherence of the Philosophers — Abū Ḥāmid al-Ghazālī
• The Journey of the Mind into God — Bonaventure

Sources and further reading

• Kalām (Britannica)
• Cosmological Argument (Stanford Encyclopedia of Philosophy)

Written by the Coordinates of Thought editors and checked against the sources above on 29 October 2026. Not peer-reviewed. How we write and check.

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