Of course, one can grasp the central theme of Walden without taking too much note of the poetic structure of the work. If one takes the attitude that one critic has — that "Walden is a collection of eighteen essays recounting Thoreau's experience at Walden Pond, near Concord, Massachusetts, from July 4, 1845, to September 6, 1847" — it would still be possible to come to the theme of Walden. But to view the work as merely a collection of essays is to miss the rich texture that Thoreau gave the work as a whole. The organic, poetic unity, and the rich symbolic structure which Thoreau created in Walden is what makes it a work far superior to his other works which present almost identical themes. And it is only by being aware of the symbolic structure that one can discover how the fiction of Thoreau's Walden is ultimately autobiographical. It is through the symbolism that one comes to see that Walden is Thoreau's artistic projection of his most deeply felt shortcomings and needs — psychological needs that are fulfilled in the fiction that Thoreau's narrator lives.
The term "fiction" is used here to describe the narrator's record of what happened to him at Walden Pond. Both the "I" voice of the narrator and the world he describes must be distinguished from the real Thoreau and the world that he inhabited while writing Walden. Walden is a fiction, an imaginative creation; it is not a strict "autobiography" in the sense that we usually assign to that word. The "I" voice we hear bragging "as lustily as chanticleer in the morning" is Thoreau's representation of himself in 1854, as he would like to be, as he hopes to be someday. Or, it is an older Thoreau's representation of the ecstasy that he felt when he was younger. In writing Walden, he is seeking to assert and perhaps recapture his former happiness.
