Personality is the collection of characteristic thoughts, feelings, and behaviors that are associated with a person. Personality traits are characteristic behaviors and feelings that are consistent and long lasting.
The ancient Greeks believed that people’s personalities depended on the kind of humor, or fluid, most prevalent in their bodies. The ancient Greeks identified four humors—blood, phlegm, black bile, and yellow bile—and categorized people’s personalities to correspond as follows:
The Greek theory of personality remained influential well into the eighteenth century.
Like the ancient Greeks, modern researchers believe in the existence of a few basic personality traits. Combinations of these basic traits, they believe, form other traits. Psychologist Raymond Cattell used a statistical procedure called factor analysis to identify basic personality traits from a very long list of English words that identified traits. Factor analysis allowed Cattell to cluster these traits into groups according to their similarities. He found that personality is made up of sixteen basic dimensions.