Children take casual comments seriously. "Quit being' so stupid," a mother says to her young son. The child might conclude, "I AM a stupid boy." He may now associate the word "stupid" not with simply making mistakes (something we all do), but with his identity as a person (who he is). He doesn't just do stupid things. He believes he IS stupid. When we identify something we are, then we have created a truth for ourselves. Judgments of being replace judgments of behavior.