Critolaus (/kraɪtoʊˈleɪəs/; Greek: Κριτόλαος Kritolaos; c. 200 – c. 118 BC)[1] of Phaselis was a Greek philosopher of the Peripatetic school. He was one of three philosophers sent to Rome in 155 BC (the other two being Carneades and Diogenes of Babylon), where their doctrines fascinated the citizens, but frightened the more conservative statesmen. None of his writings survive. He was interested in rhetoric and ethics, and considered pleasure to be an evil. He maintained the Aristotelian doctrine of the eternity of the world, and of the human race in general, directing his arguments against the Stoics.