Good definitions of emotion

Lazarus, 1991: Emotions are organized psychophysiological reactions to news about ongoing relationships with the environment.

Ekman, 1992:  Each emotion has unique features: signal, physiology, and antecedent events. Each emotion also has characteristics in common with other emotions: rapid onset, short duration, unbidden occurrence, automatic appraisal, and coherence among responses.

Evolutionary approach: emotions serve funtions.

• emotions enable rapid orientation to events in the environment (e.g. threats or opportunities)
• emotions coordinate bodily response to events
• human emotions evolved to become the bases of social relationships

Cultural approach: emotions are shaped by dynamic cultural processes.

Batja Mesquita (2001) contends that cultural approaches focus on the “practice” of emotion, in contrast to the “potential for emotion.

Oatley, Keltner, Jenkins (2006).