"Our ability to categorize and evaluate is an important part of human intelligence," says Banaji. "Without it, we couldn't survive." But stereotypes are too much of a good thing. In the course of stereotyping, a useful category—say, women—becomes freighted with additional associations, usually negative. "Stereotypes are categories that have gone too far," says John Bargh, Ph.D., of New York University. "When we use stereotypes, we take in the gender, the age, the color of the skin of the person