Three thinkers of the Islamic world stand out as important interpreters of Greek thought, and therefore, as a bridge between ancient philosophy and the Scholasticism of the Middle Ages: their Latin names are Avennasar, Averroës, and Avicenna.

Avennasar (c. 878–950), who studied with Christian Aristotelians in Baghdad (Iraq), proved so adept at applying the teachings of Aristotle (384–322 B.C.) to Muslim thought that he became known as “the second Aristotle” or the “second teacher.” He posited that philosophy and religion are not in conflict with each other; rather, they parallel one another. Also known for his work in interpreting the great Aristotle for the Muslim world, Avicenna (980–1037) is sometimes referred to as the “third teacher.” He was also the first to expand the distinction between essence and existence. Averroës (1126–1198) also was no stranger to Aristotle, writing commentaries on him as well as Plato (specifically, the Republic); he also wrote on religious law and philosophy as well as religion and logic.