Prejudice

is an affective feeling toward a person or group member based solely on their group membership. The word is often used to refer to preconceived, usually unfavorable, feelings toward people or a person because of their gender, beliefs, values, social class, age, disability, religion, sexuality, race/ethnicity, language, nationality, beauty, occupation, education, criminality, sport team affiliation or other personal characteristics. In this case, it refers to a positive or negative evaluation of another person based on their perceived group membership.

Prejudice can also refer to unfounded beliefs and may include "any unreasonable attitude that is unusually resistant to rational influence".Gordon Allport defined prejudice as a "feeling, favorable or unfavorable, toward a person or thing, prior to, or not based on, actual experience". For the Evolutionary Psychology perspective, see Prejudice from an evolutionary perspective.

The first psychological research conducted on prejudice occurred in the 1920s. This research attempted to prove white supremacy. One article from 1925 reviewing 73 studies on race concluded that the studies seemed "to indicate the mental superiority of the white race". These studies, along with other research, led many psychologists to view prejudice as a natural response to inferior races.

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