This thesis examines the influence of Ralph Waldo Emerson’s theories on the self, nature, and the sublime in Ernest Hemingway’s first and most important novel, The Sun Also Rises. Jake Barnes, Hemingway’s literary alter-ego (Latin for ‘other-self’) struggles with self-knowledge, most notably in the form of delusions of self-image and self-understanding. In his search for meaning, Jake sets out to find self-knowledge and self-direction that will provide him with the strongest possible self-confidence and emotional, inner security. As Jake strives to find his way out of insecurity and a misunderstanding of self, he engages with nature in ways that bring transformational understandings of the self that are closer to truth than to self-deception. In the process, The Sun Also Rises reveals its literary inheritance from Emerson’s thoughts on the self, nature, and self-knowledge. Hemingway’s novel shows itself as part of the Emersonian American literary tradition deeply invested in the notions of self- knowledge, individuality, will, and power. As Jake evolves in knowledge of his true self and its relation to nature, he finds that to actualize his fullest potential, he must master his will and power through acts of self-trust that are often painful and uncomfortable. For Emerson, self-reliance (i.e., self-trust) is the most significant quality of mind that an individual may possess, for it allows one to actualize his or her fullest potential. Unable to find among his compatriots anyone demonstrating strong qualities of self-reliance and willpower, Jake turns his attention to the bullfighter as the most realized figure of self-reliance and self-knowledge. Becoming as a student to a teacher, Jake Barnes finds in the presence of Romero the most complete image of sublime and limitless potential. This thesis examines in detail how Jake Barnes eventually comes to discover a fulfilling and authentic understanding of the self and of meaning in his interactions with and observations of Pedro Romero, the young matador who possesses what Emerson believes are significant human qualities: self-reliance and the limitless potential of the mind.