Robert Plutchik proposed a psychoevolutionary classification approach for general emotional responses. He considered there to be eight primary emotions—anger, fear, sadness, disgust, surprise, anticipation, trust, and joy. 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.
The framework described by Paul Ekman is influenced by Charles Darwin and Silvan Solomon Tomkins, although he himself stated that he did not accept in tot what either of them said. Ekman sustained there are three meanings for the term “basic” as you can read his argumentation in the article.
Ekman considers that emotional expressions are crucial to the development and regulation of interpersonal relationships. His studies demonstrated that facial expressions play an important role in the formation of attachments and are involved in the formation, acceleration or deceleration of aggressive behaviour.
William James, known as the father of American Psychology, developed along with his 19th Century fellow psychologist Carl Lange the James-Lange theory which considers that environmental events lead to the apparition of muscular and visceral responses, and that these responses eventually determine emotions. Instead of feeling an emotion and subsequent physiological (bodily) response, the theory proposes that the physiological change is primary, and emotion is after that experienced, as the brain reacts to the information received via the body’s nervous system.
The emotion follows the behaviour, and does not determine it.