You have to be willing to make mistakes regularly; there is nothing wrong with it. Michael taught me about making your best judgment, being wrong, making your next best judgment, being wrong, making your third best judgment, and then doubling your money.
I'm mentioning all this -- I'm mentioning all this because I think this is not merely a personal problem; you may think I'm wrong in this, but I think we live in an age when our lives are regularly punctuated by career crises, by moments when what we thought we knew -- about our lives, about our careers -- comes into contact with a threatening sort of reality.