Ancient Greek philosophers initiated a dialogue about science and the nature of reality from about 600 BC. The texts written by Greek philosophers were copied and conserved by Orthodox Christians in libraries belonging to the Byzantine Empire prior to the fall of Alexandria in 642 AD. Islamic scholars translated these texts from Greek into Arabic. Orthodox Christians continued to study the texts in Greek up to the fall of Constantinople in 1453.
Catholic Europeans at first read texts translated from Arabic into Latin. When philosophical dialogue was taken up by theologians when universities were first founded in Europe during the 13th century, many of the Latin scholars were Averroeist and Avicenna followers. But Europe was to take its own direction different to that of these Arabic philosophers. The pivot point of this new direction was the work of Thomas Aquinas himself.
Thomas Aquinas accomplished the feat of summarizing all the relevant knowledge known up to his day (1250s – 1270s). He got to grips with the writings of ancient Greek philosophers especially Aristotle, Islamic philosophers such as Avicenna and Averroes, Church Fathers especially St Augustine (354-430 AD) as well as with his contemporary Scholastic scholars. He commented on every part of the Bible which he knew in its entirety. What he bequeathed to future generations was encyclopedic knowledge from the Ancient Greeks through to the Medieval Scholasticism of his day.