“What creature,” the Sphinx asked him, “goes on four feet in the morning, on two at noonday, on three in the evening?”

The answer Oedipus gives, in Part Five, Chapter II, is “[m]an.” As a baby, man crawls; in maturity, he walks upright on his two feet; near the end of his life, he walks with a cane. Answering this riddle, Oedipus saves the city of Thebes from the curse of the Sphinx, who kills herself. Oedipus does not, however, realize the implications the riddle has for his own life.

At this point, Oedipus is chronologically between the two major criminal acts that make up his tragedy, though he commits them unknowingly. He has just killed his father, Laius, and he is about to—again unwittingly—marry his mother Jocasta. These actions divide Oedipus’s life into three stages of its own. First is the early part of his life in which he grows up as the adopted son of Polybus, from whom he flees in order to avoid fulfilling an oracle’s prophecy and committing patricide. Second is his triumphal stage, as he becomes king of Thebes and marries its widowed queen, Jocasta, after defeating the Sphinx. Third is his blinded stage, as it is revealed that Jocasta is his mother and that he has inadvertently slain his true father, Laius, on his flight from Polybus. We see that Oedipus’s life itself corresponds to the Sphinx’s riddle. At his birth, his true parents abandon him because of another prophecy, and he is forced to rely on the kindness of Polybus. At the second stage, when man stands erect, Oedipus finds himself on top of the Theban world, glorified as a hero, deemed a king, and married with children. The last stage, when man needs a cane to aid his lameness in walking, corresponds to Oedipus’s self-inflicted blindness, when he is disappointed and impaired but still alive to continue the last leg of his journey.