Tynnichus of Chalcis, a poet, mentioned in Plato's Ion:

And Tynnichus the Chalcidian affords a striking instance of what I am saying: he wrote nothing that any one would care to remember but the famous paean which is in every one's mouth, one of the finest poems ever written, simply an invention of the Muses, as he himself says. For in this way the God would seem to indicate to us and not allow us to doubt that these beautiful poems are not human, or the work of man, but divine and the work of God; and that the poets are only the interpreters of the Gods by whom they are severally possessed.

Ancient Greeks