among their soundest sciences. If this is the extent of their disagreement in it, how much greater must their disagreement be in natural philosophy or logic? And what, then, of metaphysics?

Consider, in this connection, what the authors of works on doctrines report about their mathematical and natural sciences, as related by al-Ashʿar in his book on the doctrines of non-Muslims, and by Qādī Abū Bakr in his book al-Daqāʾiq (Subtleties). These works record many times more disagreements among them than al-Shahrastānī and others who recount their doctrines mention. Their disagreements concerning mathematics—the soundest of their rational sciences—are almost beyond counting. Even the book accepted by the majority of them, Ptolemy’s Almagest, contains many propositions unsupported by sound proof, others that are disputed by other thinkers, and still others based on astronomical observations transmitted from others, which are open to error and falsehood.

The same applies to their discussions of the body in natural philosophy: is it composed of matter and form, of indivisible parts, or of neither?

Many accomplished speculative thinkers have been perplexed by these questions. Even the most acute minds among the various schools, such as Abū al-Husayn al-Basrī, Abū al-Maʿālī al-Juwaynī, and Abū ʿAbd Allāh ibn al-Khatīb, were perplexed by the question of the indivisible atom. At times they suspended judgment on it, though at other times they might adopt a definite position. Indeed, one of them may sometimes assert two contradictory positions with certainty in two books or in a book