The Greek fabulist Aesop or Esop (pronounced /ˈeɪsɒp/ ay-sop or /ˈiːsəp/ ee-səp, Greek: Αἴσωπος, Aisōpos) is given the dates c. 620-564 BCE and was by tradition born a slave (δοῦλος). Although known for the fables ascribed to him, Aesop's existence remains uncertain and no writings by him survive. Numerous fables appearing under his name were gathered across the centuries and in many languages in a storytelling tradition that continues to this day. In many of these tales animals speak and have human characteristics.