The Greeks learnt much from the Celts, including philosophy - Aristotle considered the Druids to be the inventors of philosophy and were the world's greatest scholars with mathematical skills greater than those of Pythagoras who learnt his skills from them. Druids studied for twenty years, learning geography, history, astronomy, physics and theology and spoke Latin, Greek and Hebrew. It is also thought the made human sacrifice to placate the gods. Druids had an oral teaching and wrote nothing down so we have no first hand knowledge of them. They were bards, prophets and priests. Druid is a word that orginates, it is thought, from the Gaulish or Greek words for 'oak' and 'knowledge'.
