Classic Theories of Emotion Classic theories make different claims about the origins of emotion. The James-Lange theory suggests that stimuli trigger specific physiological states, which are then experienced as emotions (a). The Cannon–Bard theory suggests that stimuli trigger both specific physiological states and emotional experiences independently (b). The two-factor theory suggests that stimuli trigger general physiological arousal whose cause the brain interprets, and this interpretation leads to emotional experience (c).