Abstract
Since the time of Heraclitus in 500 BC, scholars have speculated on and investigated the role that emotions play in shaping human behavior and reasoning abilities. The number of theories of emotion generated since this time is as vast as it is varied: for example, they include David Hume′s view of emotion as ″master over reason″ (Hume 1739), the theory that emotional feelings depend on feedback from the body (James 1884; Lange 1885), cognitive-appraisal theories (for example, Frijda 1986; Lazarus 1991; Schachter 1964; Schachter and Singer 1962), theories of basic universal emotions with associated facial expressions (Tomkins 1963; Izard 1977;