Themes are the fundamental and often universal ideas explored in a literary work.
The Hobbit’s main theme is Bilbo’s development into a hero, which more broadly represents the development of a common person into a hero. At the beginning of the story, Bilbo is timid, comfortable, and complacent in his secure little hole at Bag End. When Gandalf talks him into embarking on the quest with Thorin’s dwarves, Bilbo becomes so frightened that he faints. But as the novel progresses, Bilbo prevails in the face of danger and adversity, justifying Gandalf’s early claim that there is more to the little hobbit than meets the eye.
Bilbo possesses hidden reserves of inner strength that even Bilbo himself cannot perceive when he firsts sets out on the quest. Confronting the trolls, escaping with Gollum’s ring, slaying the spider, rescuing the dwarves in Mirkwood, and speaking face-to-face with the great dragon Smaug all provide Bilbo with opportunities to test his resolve. As he builds confidence and resourcefulness, Bilbo emerges as a true hero.
Because Tolkien acknowledged that the idea of hobbits was rooted in his experiences with rural Englishmen of his own time, Bilbo’s development might allegorically represent the heroism of England in World War I or the inner, latent heroism common to everyone. But given Tolkien’s stated distaste for allegory—his main motivation for writing was storytelling, not the exploration of a literary theme—it is questionable whether Bilbo’s story should be taken to refer to anyone except Bilbo himself.
The differences among Tolkien’s imaginary races are a major focus of the novel, particularly in its second half. Elves, dwarves, trolls, and goblins differ from one another physically, psychologically, and morally. These inherent racial differences drastically limit the possibility of individual choice but make moral distinctions easy to maintain. All goblins are evil, for example, and all elves are good. The notion of races having different moral qualities is reflected in the novel’s idea of nature. The good races are portrayed as being in harmony with nature, while the evil races are depicted as being at odds with it—hence the eagles’ decision to help the elves against the goblins. Some critics have suggested that the different races in The Hobbit were meant to represent different European nationalities, but Tolkien’s distaste for allegory makes this seem highly unlikely.
Family lineage is another important factor that shapes identity in The Hobbit. Throughout Middle-Earth, one’s prospects, character, and social position are linked closely to family heritage. Bilbo’s conflicting feelings of fear and courage, for instance, are portrayed as a struggle between his Baggins side and his Took side, referring respectively to his father’s and his mother’s families. Thorin is prompted to seek the treasure under the mountain because it is his birthright, passed down from his grandfather, Thror. Bard’s heroism is in part attributed to his having descended from the lords of Dale. Whereas race is primarily a determinant of one’s moral standing, family has more to do with one’s specific personality: Bilbo is good because he is a hobbit, but he is adventurous because he is a Took.