“Experts can sound pretty impressive, of course, especially when they bolster their claims by citing their years of training and experience in a field. Yet hundreds of studies have shown that, compared to predictions based on actuarial data, predictions based on an expert's years of training and personal experience are rarely better than chance. But when an expert is wrong, the centerpiece of his or her professional identity is threatened. Therefore, dissonance theory predicts that the more self-confident and famous experts are, the less likely they will be to admit mistakes. And that is just what Tetlock found. Experts reduced the dissonance caused by their failed forecasts by coming up with explanations of why they would have been right "if only" - if only that improbable calamity had not intervened; if only the timing of events had been different; if only blah-blah-blah.”