* You quit arguing and compare your opponent to the Nazis.  See Godwin’s law; also Reductio ad Hitlerum.

* You quit trying to make your point and attack your opponent’s biography. See any and all politicians ever.

* You cry fowl and blame the media for taking sides.  The media, already scared of being labeled unfair, takes it easy on you  See John McCain.

* You claim a special form of knowledge that the other person couldn’t possibly hope to attain.  See any and every religion ever.