Some words have fangs. Among the sharpest are those classified as negative labeling. Negative labels come in the form of adjectives: "You're lazy, selfish, unreasonable, insensitive, etc.," and also in nouns: "You're a loser, slut, bitch, bad boy, etc."
Sometimes tone of voice grows fangs on otherwise benign words. "I love you," can imply with nefarious inflection that no one else could, because you are pretty much unlovable.
In addition to the fact that negative labeling implies unchangeable characteristics of personality rather than negotiable behavior, negative labels virtually guarantee that you'll get more of the behavior you're condemning. After all, what do "lazy" people do? Well, they don't help around the house. What do "bad" kids do?
Once negatively labeled, it is never clear how many good things you have to do not to be bad anymore or how much work you have to finish to no longer be considered lazy. Early in my career I worked with a 12 year-old who had blown several foster care placements with stunts like putting out light bulbs in the middle of the night with paper clip missiles launched by a rubber band. He complained in his first session that all his life people told him he was a bad kid. "So why don't they just back the (bleep) off and let me do my job?"

















