Passage: In his 1884 article William James argued that feelings and emotions were secondary to physiological phenomena. In his theory, James proposed that the perception of what he called an "exciting fact" directly led to a physiological response, known as "emotion." To account for different types of emotional experiences, James proposed that stimuli trigger activity in the autonomic nervous system, which in turn produces an emotional experience in the brain. The Danish psychologist Carl Lange also proposed a similar theory at around the same time, and therefore this theory became known as the James–Lange theory. As James wrote, "the perception of bodily changes, as they occur, is the emotion." James further claims that "we feel sad because we cry, angry because we strike, afraid because we tremble, and either we cry, strike, or tremble because we are sorry, angry, or fearful, as the case may be."An example of this theory in action would be as follows: An emotion-evoking stimulus (snake) triggers a pattern of physiological response (increased heart rate, faster breathing, etc.), which is interpreted as a particular emotion (fear). This theory is supported by experiments in which by manipulating the bodily state induces a desired emotional state. Some people may believe that emotions give rise to emotion-specific actions, for example, "I'm crying because I'm sad," or "I ran away because I was scared." The issue with the James–Lange theory is that of causation (bodily states causing emotions and being a priori), not that of the bodily influences on emotional experience (which can be argued and is still quite prevalent today in biofeedback studies and embodiment theory).Although mostly abandoned in its original form, Tim Dalgleish argues that most contemporary neuroscientists have embraced the components of the James-Lange theory of emotions.

Question: Why does the theory originally proposed by James have a two part name attached to it?
The Danish psychologist Carl Lange also proposed a similar theory