The Incoherence of the Philosophers

Al-Ghazali (c. 1058-1111), known in the Latin West as Algazel and honoured in Islam as Hujjat al-Islam, "the Proof of Islam," is among the most consequential thinkers in the history of the faith. His most famous philosophical work, the Tahafut al-falasifa ("The Incoherence of the Philosophers"), is a searching critique of the Islamic Aristotelians, above all al-Farabi and Avicenna (Ibn Sina), whose Neoplatonised philosophy he judged to have overstepped the bounds of reason and religion. He argued that on twenty points the philosophers had failed to demonstrate their claims, and that on three they had fallen into outright unbelief: holding the world to be eternal rather than created, denying God's knowledge of particulars, and denying the bodily resurrection.

Notably, Ghazali attacked not by rejecting logic but by using it, and his discussion of causality, questioning whether the "necessary connection" between cause and effect is anything more than God's habitual ordering, is one of the classic statements of theological occasionalism and drew a celebrated reply from Averroes (the Incoherence of the Incoherence).