I get offended and argumentative with my negative self-talker. That and putting up obvious reasons why it's wrong and making fun of it. Make it give examples (or give your own of the opposite) or make fun of it for being so vague. "I am stupid" -- what is meant by that? You can't be stupid and wandering through school with your peers, they're not all stupid are they? "Challenge" your negative self-talker to be "smart"/intelligent and use bigger, more precise words. It will shut up! LOL