Final answer:
The theory of emotion that suggests 'my stomach is fluttering, therefore, I must be nervous' is the James-Lange theory, which posits that emotions result from the interpretation of physiological responses.
Step-by-step explanation:
The James-Lange Theory of Emotion
The theory of emotion you're referring to is the James-Lange theory. According to this theory, you would conclude that you are nervous because you noticed physiological changes, such as a fluttering stomach. So in a scenario where you encounter a venomous snake and your body responds with a racing heart and stomach churning, it is these physiological changes that the James-Lange theory posits result in your feeling of fear. It emphasizes that different patterns of physiological arousal are associated with different emotions, and these physical responses happen prior to the emotional experience, not simultaneously or as a result of it.
Unlike the Cannon-Bard theory, which argues that physiological arousal and emotional experience occur simultaneously and independently, or the Schachter-Singer two-factor theory, which suggests that emotions are a combination of physiological arousal and cognitive labeling, the James-Lange theory emphasizes a direct connection between the physical and the emotional. Thus, under this theory, the interpretation of bodily responses is a key factor in the emotion you end up experiencing.