Raymond Cattell
Raymond Cattell, a British and American psychologist, proposed that there are16 personality factors: warmth, intellect, emotional stability, aggressiveness, liveliness, dutifulness, social assertiveness, sensitivity, paranoia, abstractness, introversion, anxiety, open-mindedness, independence, perfectionism, and tension. Through factor analysis, Cattell was able to pinpoint the 16 primary trait constructs. These traits were identified by Cattell as common among all individuals which can me measured through the 16 PF Questionnaire. Hence, each person exhibits each of the traits to a specific degree.