The Incoherence of the Philosophers

The Incoherence of the Philosophers (تهافت الفلاسفة Tahāfut al-Falāsifaʰ in Arabic) is the title of a landmark 11th-century work by the Persian theologian Al-Ghazali and a student of the Asharite school of Islamic theology criticizing the Avicennian school of early Islamic philosophy.Muslim philosophers such as Ibn Sina (Avicenna) and Al-Farabi (Alpharabius) are denounced in this book. The belief that all causal events and interactions are not the product of material conjunctions but rather the immediate and present Will of God, underlies the work. The text was dramatically successful, and marked a milestone in the ascendance of the Asharite school within Islamic philosophy and theological discourse.

This book was preceded by a summary of Muslim philosophical thought titled: Aims of the philosophers Maqasid al-falasifah. This book is the summary of Avicenna's philosophical doctrine.Al-Ghazali stated that one must be well versed in the ideas of the philosophers before setting out to refute their ideas.

Al-Ghazali also stated that he did not find other branches of philosophy including physics, logic, astronomy or mathematics problematic. His only dispute was with metaphysics, in which he claimed that the philosophers did not use the same tools, namely logic, which they used for other sciences.

The tahafut is organized into twenty chapters in which al-Ghazali attempts to refute Avicenna's doctrines.

He states that Avicenna and his followers have erred in seventeen points (each one of which he addresses in detail in a chapter, for a total of 17 chapters) by committing heresy. But in three other chapters, he accuses them of being utterly irreligious. Among the charges that he leveled against the philosophers is their inability to prove the existence of God and inability to prove the impossibility of the existence of two gods.

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