Final answer:
Iocaste tries to prove to Oedipus that prophecies are unreliable, using the example of Laius's believed death by robbers, contrary to the prophecy of death at his son's hands.
Step-by-step explanation:
In the play Oedipus the King by Sophocles, Iocaste (or Jocasta) attempts to prove to Oedipus that prophecies are not reliable. To support this claim, she tells Oedipus about an old prophecy which said that her son would kill his father, Laius. Yet, she believes Laius was actually killed by robbers at a crossroad, not by their son. This seems to quell Oedipus's fears momentarily until the revelation that Oedipus himself had killed a man at a crossroad, aligning with the prophecy he sought to avoid. The shepherd's confirmation of Oedipus's birth and the subsequent revelation that Oedipus had indeed fulfilled the prophecy about killing his father and marrying his mother lead to the tragic resolution of the play.