The introduction of Greek philosophy and science into the culture of the Latin West in the Middle Ages was an event that transformed the intellectual life of Western Europe. It consisted of the discovery of many original works, such as those written by Aristotle in the classical period, commentaries by Hellenistic philosophers written in late Antiquity, and commentaries from early Muslim philosophers in the Arab world, or Muslim world, written during the Islamic Golden Age from the ninth to twelfth centuries.