After enough cognitive therapy sessions, I have come to believe that introspection itself is the problem. There's inherent flaws in the medium of introspection that cognitive therapy tries to correct. For example, it's cognitively easier to just tell yourself, "you're a failure" than it is to flesh out an accurate reflection: "I made a mistake filling out paperwork yesterday, and that's the second mistake this week. Although it doesn't appear to be part of a larger pattern, it happened twice, and people may start to notice. I won't get fired unless I really screw up, but I should keep on my toes, especially in this economy."

But since we don't have the capacity to say those kind of spiels to ourselves in our head, the next easiest thing is to be perpetually skeptical of our inner monologues.