The basic question must be briefly discussed—the relation of Prometheus to the new King of Heaven. Zeus is here described as a youthful tyrant, blind to all rights and interests save the security of his recent conquest. This cannot have been the picture presented by the whole trilogy. Not only is enough known of Æschylus’ religious views to make such a theory impossible; though the _Prometheus Unbound_ is lost we know the story in outline. Heracles in his wanderings came upon Prometheus, now released from Hades, but still chained to his rock and gnawed by the vulture. The hero slew the bird with an arrow, and procured the release of Prometheus by inducing the wounded Centaur Chiron to go down to death in his place, and by reconciling the Titan to Zeus, who promised to free him on hearing the secret of the fatal marriage.[229] Prometheus, to commemorate his captivity, assumed a ring of iron. The authority of the King of Gods was thus for ever established. It is only in a different atmosphere that any inconsistency can be felt. For Æschylus there was a progress in the history of Heaven as in the civilization of earth. Even Zeus in the early days of his dominion seeks to rule by might divorced from wisdom, a severance typified by his feud with Prometheus. He has his lesson to learn like all others; if he will not govern with the help of law, bowing to Fate, then the hope of the Universe is vain and the blind forces of unguided Nature, the half-quelled Titans, will bring chaos back. But youthful and harsh as he is, his will has a moral foundation, unlike theirs; and so perhaps it is that Prometheus cannot but exclaim “I sinned” in opposing that will. Upon the reconciliation between Zeus and his antagonist, Prometheus became a local Attic deity and no more. That eternal wisdom which he embodied is mysteriously assimilated into the soul of Zeus. This is the consummation; omnipotence and omniscience are at one. We arrive finally at the trilogy which bears the name ORESTEIA and which obtained the prize in 458 B.C. This is the only instance in which the whole series has survived; the satyric play, _Proteus_,[230] has perished. The name _Oresteia_ was applied to the whole tetralogy.