A prediction that becomes false as a consequence of having been made. A frequently cited example is the unexpected hanging paradox, but the prediction in that paradox is not actually self-defeating, although it appears to be. A more natural and less paradoxical example is the following: a doctor may discover that a particular patient has a strong genetic predisposition to breast cancer and may predict that she will develop the disease; but the patient may respond to the prediction by having a double mastectomy, eliminating the possibility of developing breast cancer. Also called a self-defeating prediction. See also Oedipus effect. Compare self-fulfilling prophecy.