You're So Stupid

Scott Adams is going into depth with the many ways to show how stupid someone is on the internet. He leaves out a few, like the blanket assertion. "You're stupid, everyone knows that." He also forgets the appeal to authority, "You're stupid, because I have a PhD in this very subject." That one is especially great because it is impossible to check the qualifications of an anonymous poster. Oh and of course "You made a minor grammar/spelling error, therefore you are stupid."