For the historian of ideas, interest in medieval Islamic philosophy is not something new. But this interest has been intensified with the growth of a fuller awareness of the impact this philosophy has had on the development of European thought. Overemphasis of this influence, however, can distract from treating the Islamic philosophers in their own right, that is, as philosophers who have developed ideas of their own that are intrinsic in value. The approach of these studies is thus to probe and analyze what these thinkers actually said.

The first part is devoted to Ibn Sina (Avicenna), noted for his refining the distinction between essence and existence, which constitutes the basis for his proof of God's existence and for his significant theory of universals. The second part is devoted to Avicenna's theologian-critic, Ghazali, noted for his argument that a necessary causal connection between natural events can be proven neither logically nor empirically. The third part pertains to various central themes in Islamic philosophy and includes discussions of the thought of such philosophers as Kindi, Razi, Ibn Tufayl, and Ibn Rushd (Averroes). It concludes with a discussion of the issues that divided the Islamic theologians, namely whether the value of a moral act is intrinsic to it or whether it is solely derived from the religious law.