He heard the Sphinx, however, as a riddle, setting him a problem. He heard with a heroic ear... For the mightiest man, an enigma becomes a problem to be solved, vanquished. Yet an ainigma... refers to 'all things with a second sense: symbols, oracles, Pythagorean wise-sayings.'
Hillman argues that Oedipus's heroic reduction of the Sphinx's ainigma to a solvable riddle exemplifies the ego's catastrophic failure to sustain polysemous, oracular meaning — transforming a symbol into a problem.
, Mythic Figures, 2007thesis