Written by al-Ghazali (1058-1111), The Incoherence of the Philosophers (Tahafut al falasifa) has long been recognized as a classic of Islamic thought. In it, al-Ghazali launches a vigorous attack against twenty philosophical doctrines that he sees as threatening to the Islamic faith. These doctrines include metaphysical claims about the nature and attributes of God, the nature of the world, and the possibility of miracles as well as epistemological assertions about which of these doctrines can and cannot be rationally demonstrated.
Al-Ghazali condemns seventeen of these twenty doctrines as "heretical innovations" and the remaining three as being in total opposition to Islamic belief. These three are the doctrines that the world is eternal and hence needs no creator; that God does not know particulars but only their universal characteristics—and hence does not know us as individual persons; and that bodily resurrection is impossible. While refuting rational arguments both for and against revealed doctrines, he affirms that such doctrines must be accepted on faith. For al-Ghazali, The Incoherence is more than a speculative discussion of timeless theological questions and philosophical theories, it is a defense and preservation of his religion and a voice of warning to those who have been misled by reliance on (and sometimes misunderstanding of) these philosophical doctrines.