A good word for self doubt

There's so much literature out there telling everybody to feel good that we have no idea how to feel bad. For once, I read something that acknowledged this problem.  Richard Friedman, a professor of psychiatry at Weill Cornell Medical College, writes in the NYTimes today, "The challenge of maintaining one’s self-esteem without recognition or reward is daunting. Chances are that if you are impervious to self-doubt and go on feeling good about yourself in the face of failure, you have either won the temperamental sweepstakes or you have a real problem tolerating bad news."