A part of the answer may lie in what’s called implicit social cognition, which involves the deep-rooted assumptions we all carry around and even act on without realizing it. Harvard University psychologist Mahzarin Banaji is a leader in implicit social cognition research. She excavates the hidden beliefs people hold by measuring how fast they make value judgments when shown a rapid-fire succession of stimuli, such as photographs of faces.
Scientific American - Birth of a Notion
Incredibly fascinating stuff.
