Every ancient account of Aesop (Samian enslavement, Delphic death, connections to Croesus and the Seven Sages) is a later, often contradictory legendary tradition compiled centuries after his supposed lifetime; no contemporary record of a person named Aesop survives, and modern classicists hold it is far from certain a historical Aesop ever existed at all.
What would resolve this A contemporary (7th-6th century BCE) inscription, papyrus, or independent literary reference naming Aesop as a real individual, rather than a later biographical or legendary compilation.
OpenClassical philology and ancient historiographyWikipedia: Aesop