The day he moves in is on Independence Day, July, 4. Obviously he intentionally chooses the date to make his symbolic declaration of dependence from society. Summer is a season of activity. Thoreau keeps busy in the construction work and in the bean fields. These are the examples of his self-sufficiency philosophy. But by cultivating beans, Thoreau's purpose, as I feel, is more spiritual than economic "to reap his soul harvest. Winter is a time of reflection when Thoreau likes to commune with himself indoors. It is in winter that he sets himself the task of measuring the pond, a symbol of detecting his own spiritual depth in solitude. Then spring comes back with the melting of ice and awakening of animals. The cycle of season is thus a cycle of life and spiritual regeneration.
The foremost symbol in Walden is the lake itself. Standing on the frozen pond, Thoreau notices that "Heaven is under our feet as well as over our heads.""As human beings, we perceive the world visually. Since the heaven is reflected in the pond, the world is able to gaze back at us with the eay of Walden Pond. The heaven is within the pond and Thoreau himself, and it is symbolized by the pond.Thoreau is fascinated by two aspects of the pond: its depth and its purity. He regards them as symbolic of human qualities for which we should strive. When Thoreau describes how the pond makes the swimmer's body pure white, he turns the water to a symbol of heavenly purity available to human beings on the earth. The pond is not only a natural phenomenon but also a matephor for spiritual belief. The villagers' rumor that the pond is bottomless, though proved wrong by Thoreau, indicates that humans need to believe in infinity.
Ice is an important element in Walden Pond. Since it is the only product of the pond for social use, it becomes a symbol of human exploitation of natural resources. Thoreau depicts in great details how the Irish icemen cut and carry away tons of ice for city use.
