Although The Call of the Wild is told from the perspective of an anonymous third-person narrator, the events that are recounted are those that the dog Buck experiences directly. As such, it is not unreasonable to call him the only fully developed character in the story. He is the only character whose past we know anything about, and London is careful to emphasize the human qualities of his protagonist, enabling us to empathize with the animal. Filtered through the third-person omniscience of the narrator, Buck comes across as far more than a creature of instinct, since he has a sense of wonder, shame, and justice. He also possesses a capacity for mystical experiences and for great, unselfish love, as his relationship to Thornton amply demonstrates. He may be a dog, but he is more human than many of the people around him.

Buck’s story is cyclical: he is introduced as a pampered prince, and the story concludes with Buck as a veritable king of beasts. In between, Buck undergoes experiences that provide him with greater insight about the world. Buck begins as a spoiled regent, strutting proudly over his soft, sun-kissed domain, but he abruptly sees everything taken away from him. He is reduced to nothing, beaten and kicked and forced to pull sleds through the Canadian wilderness. This experience, though, far from destroying him, makes him stronger, and he wins back his kingdom—or rather, he wins a new kingdom, a wild one that better suits his true destiny as a wild animal.

The Call of the Wild is, as its title suggests, a celebration of wildness, of primitive life, and even of savagery. Buck’s rise to greatness is not an easy path; it is a struggle, a course strewn with obstacles, from the long duel with his rival Spitz to the folly of Hal, Mercedes, and Charles. But these obstacles, London indicates, are to be rejoiced in rather than avoided: life is ultimately a long struggle for mastery, and the greatest dogs (or men), the Bucks of the world, will always seek out struggles in order to prove their greatness. Thus, when Buck goes from being a moral, civilized pet to a fierce, bloodthirsty, violent wolf-dog, we are glad rather than shocked, because we know that he is fulfilling his highest -possible destiny.