theory was extended to provide the basis for an explanation for psychological defence mechanisms; Plutchik proposed that eight defense mechanisms were manifestations of the eight core emotions. Publications Plutchik contributed the "Emotions" article to the encyclopedia, World Book Millennium 2000. Notes References External links The Nature of Emotions, a model that describes the relations among emotion concepts. Plutchik's Theory of Emotions The Nature of Emotions (American Scientist Vol. 89, No. 4 (July–August 2001), pp. 344–350) 20th-century American psychologists Emotion psychologists 1927 births 2006 deaths Columbia University alumni University of South Florida faculty Yeshiva University faculty