And so presuming that perhaps not everyone is familiar with the myth of Oedipus the King, I'll direct you here for a brief summary of the plot.
Now there are a variety of interpretations as to Oedipus's tragic flaw - his pride, his ignorance of his own background, his disregard for the prophesy of the oracle.
But I'd like to propose a slightly different interpretation - not mine own, and I can't recall who precisely shared it with me, but it begins with the riddle posed by the Sphinx: "Which creature has one voice and yet becomes four-footed and two-footed and three-footed?", to which Oedipus answered: "Man—who crawls on all fours as a baby, then walks on two feet as an adult, and then uses a walking stick in old age.".
Now Oedipus's answer is, strictly speaking, correct, but he errs in his answer by saying "Man" - the answer should be "Myself". And in answering it in the general - as opposed to the specific, he is distancing himself from his own humanity, in a way placing himself above it. The Sphinx, riddle answered, has no choice but to destroy herself, and Oedipus is free to proceed, but in his refusal to acknowledge his own humanity, mortality and place in the world he fulfills the prophesy in the most heinous way possible - Pride, therefore, is the undoing of Oedipus.