and Aristotle" and on "The object before Plato and Aristotle." In essays "Against Galen" and "Against John Philoponus" he criticised the views of those commentators, and endeavoured to defend the orthodoxy of Aristotle by making them responsible for apparent discrepancies with the teaching of revelation. He was interested also in the occult sciences, as appears from his treatises "On geomancy," "On the Jinn," and "On dreams." His chemical treatise called kimiya t-Tabish, "the chemistry of things heated," has been classed as a work on natural science and also as a treatise on magic; this was the unfortunate direction which Arabic chemistry was taking. He also wrote several works on music. (Cf. Schmölders: Documenta Philos. Arab. Bonn., 1836, for Latin versions of select treatises).
As we have already noted, his primary importance was as a teacher of logic. A great deal of what he has written is simply a reproduction of the outlines of the Aristotelian logic and an exposition of its principles, but De Vaux (Avicenne, pp. 94–97) has drawn attention to evidences of original thought in his "Letter in reply to certain questions."
Like al-Kindi he accepted the Theology as a genuine work of Aristotle, and shows very clear traces of its influences. In his treatise "On the intelligence" he makes a careful analysis of the way in which the term 'aql (reason, intelligence, spirit) is employed in general speech and in philosophical enquiry. In common language "a man of intelligence" denotes a man of