'Ancient philosophy' is the conventional title, in Europe and the English-speaking academy, for the philosophical activities of the thinkers of the Graeco-Roman world. It includes a succession of philosophers who operated over a 1,000-year period from the middle of the first millennium BC to the middle of the first millennium AD - from Thales and the earliest Pre-Socratics to late Neoplatonists and Aristotelian commentators, such as Simplicius and Philoponus. Later thinkers in Europe (e.g. Scotus Eriugena) are normally assigned to the category 'medieval', as are Arabic philosophers such as Avicenna and Averroës. Contemporary philosophers from other cultures (e.g. Confucius, Buddha) are also not included.