Metis ("counsel," "cunning intelligence") was an Oceanid, daughter of Oceanus and Tethys, and the first wife of Zeus. She was, in Hesiodic tradition, the wisest of all the gods and goddesses; it was Metis who gave Cronus the emetic by which he disgorged the swallowed Olympians, and so she was instrumental in the very foundation of Zeus's kingship. But it was prophesied that any child she bore would surpass its father in wisdom and might overthrow him; and Zeus, mindful of how he himself had overthrown his father, dealt with the problem by swallowing Metis whole when she was already pregnant. She continued to give him counsel from within (Zeus thereafter being the cleverest of gods, having Metis inside him); and when the time came for her child to be born, Zeus suffered such a headache that Hephaestus split his head with an axe — and Athena emerged in full armor, the daughter of Zeus and Metis, born from her father's head because her mother was already inside him.
The Metis-swallowing is one of the more striking episodes of theogonic violence in the Hesiodic tradition, and its symbolic point — that the sovereign god incorporates wisdom rather than being subject to it, and that the wise daughter Athena springs from the head of the father rather than from the womb of a separate mother — has not gone unnoticed by modern interpreters.







