Oedipus paid no attention to this news; for he little suspected that the old man whom he had killed was the king, whom everybody loved, and for whom they now mourned with noisy grief.

He was, however, deeply interested in the story of the Sphinx; and he was so sure that he could guess the riddle, that he immediately set out to find the monster. He walked boldly along the road until stopped by the Sphinx, which told him to answer this riddle if he wished to live: “What creature walks upon four feet in the morning, upon two at noon, and upon three at night?”