The 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. Like colors, primary emotions can be expressed at different intensities and can mix with one another to form different emotions. Additionally, his circumplex model makes connections between the idea of an emotion circle and a color wheel. He suggested 8 primary bipolar emotions: joy versus sadness anger versus fear trust versus disgust and surprise versus anticipation. Plutchik first proposed his cone-shaped model (3D) or the wheel model (2D) in 1980 to describe how emotions were related. Plutchik also created a wheel of emotions to illustrate different emotions. Plutchik's wheel of emotions Plutchik's wheel of emotions Each emotion can exist in varying degrees of intensity or levels of arousal.All emotions vary in their degree of similarity to one another.Primary emotions can be conceptualized in terms of pairs of polar opposites.Primary emotions are hypothetical constructs or idealized states whose properties and characteristics can only be inferred from various kinds of evidence.All other emotions are mixed or derivative states that is, they occur as combinations, mixtures, or compounds of the primary emotions.There is a small number of basic, primary, or prototype emotions.Despite different forms of expression of emotions in different species, there are certain common elements, or prototype patterns, that can be identified.Emotions served an adaptive role in helping organisms deal with key survival issues posed by the environment.Emotions have an evolutionary history and have evolved various forms of expression in different species.The concept of emotion is applicable to all evolutionary levels and applies to all animals including humans.Plutchik's psychoevolutionary theory of basic emotions has ten postulates. Plutchik argues for the primacy of these emotions by showing each to be the trigger of behaviour with high survival value, such as the way fear inspires the fight-or-flight response. He considered there to be eight primary emotions- anger, fear, sadness, disgust, surprise, anticipation, trust, and joy.

Plutchik proposed a psychoevolutionary classification approach for general emotional responses. His research interests included the study of emotions, the study of suicide and violence, and the study of the psychotherapy process. He authored or coauthored more than 260 articles, 45 chapters and eight books and edited seven books. from Columbia University and he was also a psychologist. Robert Plutchik (21 October 1927 – 29 April 2006) was a professor emeritus at the Albert Einstein College of Medicine and adjunct professor at the University of South Florida.

Emotions color wheel overview