"Mythos" and "logos" are terms that evolved throughout classical Greek history. In the times of Homer and Hesiod (8th century BC) they were essentially synonyms, and contained the meaning of 'tale' or 'history'. Later came historians like Herodotus and Thucydides, as well as philosophers like Heraclitus and Parmenides and other Presocratics who introduced a distinction between both terms; mythos became more a "nonverifiable account", and logos a "rational account". It may seem that Plato, being a disciple of Socrates and a strong partisan of philosophy based on "logos", should have avoided the use of myth-telling. Instead he made an abundant use of it. This fact has produced analytical and interpretative work, in order to clarify the reasons and purposes for that use.